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PRIVILEGED & CONFIDENTIAL ATTORNEY WORK PRODUCT — ATTORNEY-CLIENT PRIVILEGE

MEMORANDUM

September 15, 2023

FROM: Wendy Schultz, Working Associate Calderwood & Harkness LLP 600 Lexington Avenue, 30th Floor New York, NY 10022

TO: Marcus Delgado, Responsible Partner, intellectual Property Calderwood & Harkness LLP

RE: Freedom-to-Operate Summary — Compound PPC-4187 (Penteracitinib) in Licensed Territory

CLIENT: Penterra Pharmaceuticals Corp. ("Penterra" or "PPC")

MATTER: Out-License of PPC-4187 to Meridian Bio Therapeutics Limited ("Meridian")

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I. EXECUTIVE SUMMARY

The purpose of this memorandum is to summarize and analyze the freedom-to-operate ("FTO") opinion provided by Whitford & Cascade Insurance Brokers ("W&M"), Penterra's patent prosecution counsel, for the manufacture, use, sale, offer for sale, and importation of PPC-4187 (proposed International Nonproprietary Name ("INN"): Penteracitinib; proposed trade name: PENTECLAR) across the Licensed Territory defined in the Exclusive License Agreement between Penterra and Meridian Bio Therapeutics Limited ("Meridian"). This memorandum is prepared in connection with Calderwood & Harkness's representation of Penterra in the out-license of PPC-4187 to Meridian and is intended to assist the deal team in assessing intellectual property risk for purposes of structuring and finalizing the Exclusive License Agreement.

The Licensed Territory, as defined in the current draft of the Exclusive License Agreement, comprises the following twelve jurisdictions: the People's Republic of China (including Hong Kong Special Administrative Region and Macau Special Administrative Region), Japan, the Republic of Korea, Australia, New Zealand, Singapore, Thailand, Malaysia, Indonesia, the Philippines, Vietnam, and Taiwan (collectively, the "Licensed Territory" or "Territory").

The W&M FTO opinion was authored by Dr. Alan J. Whitford, Lead Patent Attorney, of Whitford & Cascade Insurance Brokers, 1750 K Street NW, Suite 600, Washington, DC 20006. Dr. Whitford has served as Penterra's lead patent prosecution counsel since the inception of the PPC-4187 patent portfolio in 2018 and possesses extensive familiarity with the compound's chemical structure, mechanism of action, and patent landscape. The W&M opinion, dated August 28, 2023, was delivered to Penterra's General Counsel, Anita M. Fremont, and subsequently provided to Calderwood & Harkness under the common interest privilege for purposes of the out-license transaction.

Overall Conclusion. Based on our review of the W&M FTO opinion and our independent analysis of the underlying claim charts, prosecution histories, and relevant prior art, the overall conclusion is that there is a low risk of infringement of third-party patents in the Licensed Territory for the development, manufacture, and commercialization of PPC-4187 in its current 25 mg and 50 mg film-coated tablet formulation as a selective Janus kinase 1 ("JAK1") inhibitor for the treatment of moderate-to-severe atopic dermatitis in adults. W&M identified no third-party patent that presents a high risk of infringement across any of the twelve jurisdictions comprising the Licensed Territory. While certain third-party patent families were identified as requiring detailed claim construction analysis, in each instance W&M concluded — and we concur — that PPC-4187 does not infringe the relevant claims, whether analyzed under literal infringement or applicable equivalents doctrines.

This favorable FTO assessment supports Penterra's ability to provide customary intellectual property representations, warranties, and indemnification obligations under the Exclusive License Agreement and is an important consideration in the deal team's overall risk assessment for the transaction.

II. BACKGROUND

A. The Compound — PPC-4187

PPC-4187 is a novel, selective Janus kinase 1 (JAK1) inhibitor being developed as an oral, once-daily tablet formulation for the treatment of moderate-to-severe atopic dermatitis in adults. The compound was discovered by Penterra's internal medicinal chemistry team and is designed to achieve high selectivity for JAK1 over JAK2, JAK3, and TYK2, thereby potentially offering an improved safety profile relative to pan-JAK inhibitors currently on the market or in late-stage development.

The proposed International Nonproprietary Name (INN) for PPC-4187 is "Penteracitinib," reflecting the compound's membership in the "-citinib" stem class of JAK inhibitors. Penterra intends to commercialize the compound under the proposed trade name PENTECLAR in both the retained territory (United States and European Union/EEA) and, through its licensee Meridian, in the Licensed Territory.

PPC-4187 is currently in the Phase IIb stage of clinical development. Penterra sponsored and completed Study PPC-4187-201, a randomized, double-blind, placebo-controlled, dose-ranging Phase IIb trial conducted at approximately 75 sites across the United States and the European Union. The study enrolled 420 adult patients with moderate-to-severe atopic dermatitis. Topline results were announced in June 2023 and demonstrated statistically significant improvement in the primary endpoint — the proportion of patients achieving at least a 75% improvement from baseline in the Eczema Area and Severity Index (EASI-75) at Week 16 — compared with placebo (p<0.001 for both the 25 mg and 50 mg dose groups). Secondary endpoints, including IGA 0/1 response and pruritus NRS improvement, also showed statistically significant improvements over placebo. The safety profile observed in the Phase IIb study was consistent with the known class effects of JAK1-selective inhibitors, with no unexpected safety signals identified.

The compound is designated by the internal code PPC-4187. The dosage strengths under development are 25 mg and 50 mg film-coated tablets for oral administration. The chemistry, manufacturing, and controls (CMC) package for PPC-4187 has been validated, with manufacturing of both drug substance and drug product conducted at Alkerra Manufacturing Inc., located at 5200 Meridian Parkway, Research Triangle Park, NC 27713. Alkerra serves as Penterra's contract manufacturing organization and has been qualified under current Good Manufacturing Practice (cGMP) standards. The manufacturing process is the subject of certain of Penterra's proprietary patent filings, as described in Section II.B below.

B. Penterra's Own IP Portfolio

Penterra has developed a robust intellectual property portfolio around PPC-4187, comprising seven patent families that collectively cover composition of matter, crystalline forms (including the commercial Form A polymorph), methods of use for the treatment of atopic dermatitis and other JAK1-mediated inflammatory conditions, pharmaceutical formulation (including the film-coated tablet), and the manufacturing process for drug substance synthesis.

The following key granted patents in the Licensed Territory are relevant to the FTO analysis and to the overall IP landscape being licensed to Meridian:

• CN Patent No. ZL 2020 1 0456789.0 — Composition of Matter. Granted by the China National intellectual Property Administration (CNIPA). Covers the PPC-4187 compound per se, including pharmaceutically acceptable salts and solvates thereof. Expiration date: August 12, 2037.

• JP Patent No. 7,012,345 — Composition of Matter. Granted by the Japan Patent Office (JPO). Covers the PPC-4187 compound per se and pharmaceutical compositions containing the same. Expiration date: August 12, 2037.

• KR Patent No. 10-2345678 — Composition of Matter. Granted by the Korean intellectual Property Office (KIPO). Covers the PPC-4187 compound and methods of preparing the same. Expiration date: August 12, 2037.

• AU Patent No. 2020234567 — Composition of Matter. Granted by IP Australia. Covers the PPC-4187 compound per se. Expiration date: August 12, 2037.

National phase entries from PCT/US2019/045123 (the foundational PCT application covering PPC-4187 composition of matter) have been filed and are either granted or pending in Japan, China, the Republic of Korea, Australia, Singapore, and six ASEAN countries within the Licensed Territory. Prosecution in Singapore, Thailand, Malaysia, Indonesia, the Philippines, and Vietnam is ongoing, with no material prior art rejections received to date.

For portfolio context, though the United States and the European Union are within Penterra's retained territory, we note the following U.S. patents:

• U.S. Patent No. 11,234,567 — Composition of Matter. Covers the PPC-4187 compound per se, pharmaceutically acceptable salts, and pharmaceutical compositions. Expiration date: August 12, 2037.

• U.S. Patent No. 11,345,678 — Crystalline Form A. Covers the crystalline Form A polymorph of PPC-4187, characterized by specific X-ray powder diffraction (XRPD) peaks. Expiration date: November 3, 2038.

The proposed trade name PENTECLAR has been filed as a trademark application in China, Hong Kong SAR, Japan, the Republic of Korea, Australia, and additional Territory jurisdictions. In the United States, PENTECLAR has been registered as U.S. Trademark Registration No. 6,789,012. Trademark clearance in the Licensed Territory is being handled separately by Calderwood & Harkness's trademark group and is not addressed in this FTO memorandum.

C. Scope of W&M FTO Analysis

W&M was engaged by Penterra in March 2023 to conduct comprehensive patent landscape searches and FTO analysis across all twelve jurisdictions comprising the Licensed Territory. The engagement was structured to provide Penterra with an assessment of the risk that the development, manufacture, use, sale, offer for sale, and importation of PPC-4187 in the Licensed Territory would infringe valid and enforceable third-party patent rights.

The scope of W&M's analysis covered the following five technical categories:

(i) Composition of matter / active ingredient — claims directed to the PPC-4187 compound per se or to genera of compounds within which PPC-4187 might fall;

(ii) Crystalline polymorphs — claims directed to specific crystalline forms of JAK inhibitors, including crystalline forms that might overlap with Penterra's commercial Form A polymorph;

(iii) Pharmaceutical formulations — claims directed to oral solid dosage forms, film-coated tablets, or specific excipient combinations relevant to PPC-4187's finished drug product;

(iv) Methods of treatment — claims directed to the use of JAK inhibitors, JAK1-selective inhibitors, or specific compounds for the treatment of atopic dermatitis, inflammatory skin conditions, or related JAK1-mediated disorders; and

(v) Manufacturing processes — claims directed to synthetic routes, intermediate compounds, or process conditions relevant to the manufacture of PPC-4187 drug substance.

W&M consulted the patent registries and databases maintained by each national patent office within the Licensed Territory, including CNIPA (China), JPO (Japan), KIPO (Republic of Korea), IP Australia, IPONZ (New Zealand), IPOS (Singapore), DIP Thailand, MyIPO (Malaysia), DGIP Indonesia, IPOPHL (Philippines), NOIP (Vietnam), and TIPO (Taiwan). In addition, W&M conducted searches using WIPO PATENTSCOPE to identify PCT applications designating any of the foregoing jurisdictions. Commercial patent databases, including Pemberton Data Systems, Orbit intelligence, and Marlowe Solutions, were also utilized to supplement the national registry searches and to identify patent family relationships across jurisdictions.

The cut-off date for the prior art search was August 2023. W&M acknowledges, and we concur, that patent applications filed within the eighteen-month priority period prior to the search cut-off date may not yet have been published and therefore would not be captured by the search.

In total, W&M reviewed approximately 340 third-party patent families identified as potentially relevant across the Licensed Territory. The identification, classification, and analysis of these families is described in greater detail in Sections III and IV below.

III. METHODOLOGY

W&M employed a multi-layered search methodology designed to maximize coverage and minimize the risk of overlooking relevant third-party patent rights. The methodology comprised three principal search approaches, which were applied across all twelve jurisdictions in the Licensed Territory.

Keyword Searches. W&M conducted keyword searches using terms related to PPC-4187's chemical name, proposed INN (penteracitinib), mechanism of action (JAK1 inhibitor, Janus kinase inhibitor, selective JAK inhibitor), therapeutic indication (atopic dermatitis, eczema, inflammatory skin disease, dermatitis), and formulation characteristics (film-coated tablet, oral solid dosage form, immediate-release tablet). Keyword searches were conducted in English and, where applicable, in the local language of the relevant jurisdiction (Mandarin Chinese for CNIPA, Japanese for JPO, Korean for KIPO, and Traditional Chinese for TIPO). W&M engaged local language specialists to assist with the non-English keyword searches to ensure comprehensive coverage.

Structure-Based Searches. W&M conducted chemical substructure searches using the Markush structure of PPC-4187 and its key structural motifs, including the pyrazole ring system, the core heterocyclic scaffold, and the acylamino substituent. These structure-based searches were designed to identify third-party patents claiming genera of compounds that might encompass PPC-4187 or close structural analogs. The structure searches were conducted using Pemberton Data Systems's chemical structure search module and STN/Fenmore Health IT.

Classification Code Searches. W&M supplemented the keyword and structure-based searches with searches based on International Patent Classification (IPC) and Cooperative Patent Classification (CPC) codes relevant to JAK inhibitors (e.g., C07D class codes for heterocyclic compounds; A61K 31/ codes for pharmaceutical compositions containing nitrogen heterocycles; A61P 17/00 for dermatological agents).

Risk Tier Classification. Following identification, the approximately 340 third-party patent families were classified into three risk tiers:

(A) High — Close structural or functional overlap with PPC-4187; claims that, on their face, might be construed to encompass the PPC-4187 compound, formulation, or method of use; requiring detailed claim construction and infringement analysis.

(B) Moderate — Tangential overlap with PPC-4187; claims that touch upon the same general technical space (JAK inhibitors, atopic dermatitis treatments) but that, upon initial review, appear distinguishable; requiring detailed claim analysis to confirm non-infringement.

(C) Low — Peripheral relevance only; claims directed to structurally distinct compounds, different formulation types, or unrelated methods of treatment; easily designed around or clearly non-infringed.

Of the approximately 340 families identified, W&M classified approximately 12 families as Tier A (High), approximately 45 families as Tier B (Moderate), and the remaining approximately 283 families as Tier C (Low). Each Tier A and Tier B family was subjected to detailed claim construction analysis, including review of the claims as granted (or as published, in the case of pending applications), the patent specification, the prosecution history (where available), and relevant prior art. Claim charts were prepared for each Tier A family and for selected Tier B families.

Claim Construction Approach. W&M applied jurisdiction-specific claim construction standards in analyzing third-party patent claims, recognizing that the approach to claim interpretation varies across the Licensed Territory. In particular:

• China: W&M applied the CNIPA Patent Examination Guidelines and relevant Supreme People's Court judicial interpretations regarding patent claim construction, including the principle that claims should be interpreted in light of the specification and drawings but are not limited thereto. W&M also considered the applicability of the doctrine of equivalents under Chinese patent law.

• Japan: W&M applied the JPO Examination Guidelines for Patent and Utility Model and relevant case law from the intellectual Property High Court, including the five-factor test for the doctrine of equivalents established in the Supreme Court's Ball Spline Bearing decision (1998). W&M engaged Nakamura & Takeda Law Offices in Tokyo to provide local counsel input on the application of the Japanese doctrine of equivalents and on Pharmaceuticals and Medical Devices Agency (PMDA) regulatory patent linkage considerations relevant to PPC-4187.

• Republic of Korea: W&M applied KIPO claim construction standards, including the Korean Supreme Court's framework for interpreting patent claims in light of the specification and prosecution history.

• Australia: W&M applied the principles of purposive construction as articulated by the High Court of Australia and the Federal Court, interpreting claims by reference to the specification as a whole and the understanding of the person skilled in the art.

• Other Territory Jurisdictions: For jurisdictions with less developed patent jurisprudence in the pharmaceutical space (e.g., certain ASEAN jurisdictions), W&M applied general principles of patent claim construction consistent with the applicable national patent law and, where available, relevant administrative guidelines.

W&M's methodology is consistent with industry best practices for pharmaceutical FTO analyses and, in our view, was thorough and appropriately comprehensive for the purposes of the Penterra/Meridian out-license transaction.

IV. JURISDICTION-BY-JURISDICTION FTO ANALYSIS

The following sections summarize W&M's FTO findings for each of the twelve jurisdictions in the Licensed Territory. For each jurisdiction, we identify the number of third-party patent families reviewed, highlight the most noteworthy third-party patents analyzed, summarize W&M's conclusions, and provide an overall risk assessment.

A. People's Republic of China (Including Hong Kong SAR and Macau SAR)

China represents the largest single market within the Licensed Territory for PPC-4187 and, accordingly, was the subject of the most extensive patent landscape search. W&M identified approximately 85 third-party patent families with potential relevance to PPC-4187 in China. Of these, seven families were classified as Tier A (High) or Tier B (Moderate) and were subjected to detailed claim construction analysis.

The following third-party patents were among the most closely analyzed:

1. Novagenix Biosciences Ltd. — CN Patent No. ZL 2017 1 0892345.6 (and related family members). This patent family includes claims directed to a broad genus of JAK inhibitor compounds characterized by a substituted pyrrolo-pyrimidine core scaffold. The genus is defined by a Markush structure with multiple variable substituents. W&M conducted a detailed structural comparison of PPC-4187 against the genus definition and concluded that PPC-4187 falls outside the claimed genus due to specific structural differentiation at the pyrazole moiety. The Novagenix claims require a fused bicyclic ring system at the R2 position that is absent from PPC-4187's structure. Moreover, the Novagenix patent specification contains no disclosure of PPC-4187 or any compound structurally analogous thereto, and the prosecution history reflects that the applicant narrowed the claims during prosecution in response to prior art rejections. W&M's conclusion: non-infringement; low risk.

2. Zenlong Pharma Co., Ltd. — CN Patent No. ZL 2019 1 0345678.2 (and related family members). This patent family includes claims directed to pharmaceutical formulations of JAK1-selective inhibitors in the form of oral solid dosage forms. The independent claims specify the use of particular excipient combinations, including hydroxypropyl methylcellulose acetate succinate (HPMCAS) as a matrix-forming polymer and specific disintegrant ratios. W&M reviewed PPC-4187's film-coated tablet formulation in detail and determined that PPC-4187 does not utilize HPMCAS or the specific excipient combinations recited in the Zenlong claims. The formulation of PPC-4187 employs different excipients, including microcrystalline cellulose as the principal filler and croscarmellose sodium as the disintegrant, in ratios and combinations not covered by the Zenlong claims. W&M's conclusion: non-infringement; low risk.

3. Daiho Pharmaceutical Corp. — CN Patent No. ZL 2018 1 0567890.3 (and related family members). This patent family includes claims directed to methods of treating inflammatory skin conditions, including atopic dermatitis, using a combination therapy comprising a JAK inhibitor and a topical corticosteroid administered concurrently. The independent method claims expressly require the co-administration of both a JAK inhibitor and a topical corticosteroid. Because PPC-4187 is being developed as a monotherapy — and Penterra's current clinical development program does not contemplate mandatory co-administration with a topical corticosteroid — the Daiho method claims are not practiced by the manufacture, sale, or use of PPC-4187 as a monotherapy for moderate-to-severe atopic dermatitis. W&M's conclusion: non-infringement; low risk. W&M noted, however, that if Penterra or Meridian were to pursue a combination therapy indication requiring co-administration with a topical corticosteroid, the Daiho patent family would require re-evaluation.

The remaining patent families identified in China were classified as Tier C (Low) and, upon review, were determined to be directed to structurally distinct compounds, unrelated formulation types, or methods of treatment for conditions other than atopic dermatitis. None of these families raised material infringement concerns for PPC-4187.

Overall China Risk Assessment: LOW.

We note that Penterra's own CN Patent No. ZL 2020 1 0456789.0 provides strong composition-of-matter protection for PPC-4187 in China through August 12, 2037. This patent provides Penterra (and, through the license, Meridian) with an affirmative right to exclude third parties from making, using, selling, or importing PPC-4187 in China and serves as a significant defensive asset in any potential patent dispute.

With respect to Hong Kong SAR and Macau SAR, W&M confirmed that the patent landscape is substantially similar to that of mainland China for purposes of this analysis. Hong Kong operates a re-registration system for short-term patents and a standard patent system based on grants from designated patent offices (including CNIPA). Macau's patent system relies on registration of patents granted by certain designated offices. W&M identified no additional third-party patent risks specific to Hong Kong or Macau beyond those analyzed for mainland China.

B. Japan

Japan represents the second-largest single market within the Licensed Territory and has a well-developed pharmaceutical patent landscape with robust examination and enforcement mechanisms. W&M identified approximately 60 third-party patent families with potential relevance to PPC-4187 in Japan. Of these, three families were classified as Tier A and subjected to detailed claim construction analysis, with input from Nakamura & Takeda Law Offices in Tokyo.

The following third-party patents were among the most closely analyzed:

1. Kitagawa Chemical Industries K.K. — JP Patent No. 6,890,123 (and related family members). This patent family includes claims directed to heteroaryl JAK inhibitors defined by a substituted pyridazine core scaffold with various heterocyclic substituents. W&M conducted a detailed comparison of PPC-4187's core scaffold against the Kitagawa claims and concluded that PPC-4187 is structurally distinct. Specifically, PPC-4187 features a pyrazolo-pyrimidine core, which differs from the pyridazine core recited in the Kitagawa claims in both ring size and heteroatom positioning. W&M further analyzed the claims under the five-factor doctrine of equivalents test articulated by the Japanese Supreme Court and concluded that PPC-4187 would not be found to infringe under the doctrine of equivalents. The structural differences between PPC-4187 and the claimed genus are not merely insubstantial variations but reflect fundamental differences in the core ring system that would be recognized by a person skilled in the art as resulting in different pharmacological properties and binding characteristics. Nakamura & Takeda Law Offices concurred in this assessment. W&M's conclusion: non-infringement under both literal and equivalents analysis; low risk.

2. Sanwa Pharma K.K. — JP Patent No. 6,945,678 (and related family members). This patent family includes claims directed to specific crystalline forms of JAK inhibitor compounds, characterized by X-ray powder diffraction (XRPD) patterns with enumerated peak positions and relative intensities. W&M compared the XRPD data for Penterra's commercial Form A polymorph against the crystalline form claims in the Sanwa patent and determined that the claimed crystalline forms exhibit distinct XRPD patterns that do not overlap with Penterra's Form A. Specifically, the Sanwa claims require characteristic XRPD peaks at 2θ values of 8.2°, 14.7°, 19.1°, and 22.6° (±0.2°), whereas Penterra's Form A exhibits characteristic peaks at 2θ values of 7.5°, 12.3°, 17.8°, and 24.1° (±0.2°). The claimed polymorphs are directed to different compounds entirely (substituted imidazopyridine JAK inhibitors) and the crystalline forms are of a different chemical entity. W&M's conclusion: non-infringement; low risk.

The remaining patent families identified in Japan were classified as Tier B or Tier C and, upon analysis, were determined to present no material infringement risk for PPC-4187. Several families were directed to second-generation JAK inhibitor compounds with distinct structural scaffolds, and others were directed to combination therapy methods not practiced by PPC-4187 monotherapy.

Overall Japan Risk Assessment: LOW.

Penterra's JP Patent No. 7,012,345 (composition of matter) provides strong protection for PPC-4187 in Japan through August 12, 2037. W&M, in coordination with Nakamura & Takeda Law Offices, also considered the implications of the Japanese patent linkage system administered by the PMDA in connection with the listing of patents on the PMDA's patent information registry (the so-called "Orange Book" equivalent). Penterra's composition-of-matter patent is expected to be listed on the PMDA registry upon regulatory approval of PPC-4187 in Japan, which will provide an additional layer of patent protection against generic entry.

C. Republic of Korea

South Korea is a significant market within the Licensed Territory, with well-developed pharmaceutical patent examination and enforcement regimes. W&M identified approximately 40 third-party patent families with potential relevance to PPC-4187 in the Republic of Korea. Of these, two families were classified as Tier A or Tier B and subjected to detailed claim construction analysis.

The most notable third-party patent analyzed was the following:

1. HanVita Biopharma Inc. — KR Patent No. 10-1987654 (and related family members). This patent family includes claims directed to substituted pyrrolo-pyrimidine JAK inhibitors for the treatment of inflammatory and autoimmune diseases. The independent claims define a genus of compounds using a Markush structure centered on a pyrrolo[2,3-d]pyrimidine ring system. Upon initial review, this patent family was classified as Tier A due to the superficial structural similarity between the pyrrolo-pyrimidine scaffold recited in the HanVita claims and PPC-4187's core heterocyclic framework.

However, upon detailed claim construction analysis, W&M concluded that PPC-4187 does not satisfy all claim limitations of the HanVita patent. Specifically, the HanVita claims require a pyrrolo[2,3-d]pyrimidine ring system with a specific substitution pattern at the C-4 and N-7 positions that is absent from PPC-4187's structure. PPC-4187 employs a pyrazolo[1,5-a]pyrimidine ring system — a different heterocyclic framework with different connectivity, ring fusion, and heteroatom positioning. The distinction between the pyrrolo[2,3-d]pyrimidine and pyrazolo[1,5-a]pyrimidine ring systems is well-recognized in the medicinal chemistry literature and would be understood by a person skilled in the art as representing a fundamental structural difference, not an insubstantial variation. W&M assessed this as a low-to-moderate risk upon initial classification but, following detailed analysis, ultimately concluded that PPC-4187 is non-infringing of the HanVita claims. We concur in this assessment.

The remaining patent families identified in South Korea were classified as Tier C and did not raise material infringement concerns.

Overall Korea Risk Assessment: LOW.

Penterra's KR Patent No. 10-2345678 (composition of matter) provides protection for PPC-4187 in the Republic of Korea through August 12, 2037.

D. Australia

Australia maintains a well-established pharmaceutical patent examination and enforcement system administered by IP Australia and the Federal Court of Australia. W&M identified approximately 30 third-party patent families with potential relevance to PPC-4187 in Australia.

Upon review, no third-party patents were identified with claims that would be infringed by PPC-4187's composition, formulation, or use. The patent families identified in Australia were largely counterparts of families already analyzed in the context of other Territory jurisdictions (principally China and Japan), and the conclusions reached for those jurisdictions applied equally to the Australian counterparts. Several Australian patent families directed to JAK inhibitor compounds were reviewed and found to claim structurally distinct compounds with no overlap with PPC-4187.

Overall Australia Risk Assessment: LOW.

Penterra's AU Patent No. 2020234567 provides composition-of-matter protection for PPC-4187 in Australia through August 12, 2037. Australia's patent term extension regime under the Patents Act 1990 (Cth) may provide an opportunity for patent term extension for AU Patent No. 2020234567 upon regulatory approval of PPC-4187 by the Therapeutic Goods Administration (TGA), subject to eligibility requirements.

E. New Zealand

New Zealand follows a patent framework that is broadly similar to Australia's, and its pharmaceutical patent landscape overlaps substantially with Australia's. W&M identified approximately 15 third-party patent families with potential relevance to PPC-4187 in New Zealand. Many of these families were counterparts of the same families reviewed in the Australian analysis.

Upon review, no material infringement risks were identified. The third-party patent families present in New Zealand were directed to structurally distinct JAK inhibitor compounds, unrelated formulation types, or methods of treatment for non-dermatological indications.

Overall New Zealand Risk Assessment: LOW.

Penterra's national phase application from PCT/US2019/045123 is pending in New Zealand, and prosecution is proceeding without material objections.

F. Singapore

Singapore maintains a well-organized patent system administered by the intellectual Property Office of Singapore (IPOS). Penterra's national phase entry from PCT/US2019/045123 has been filed in Singapore and is currently pending. W&M identified approximately 20 third-party patent families with potential relevance to PPC-4187 in Singapore.

Upon review, no material infringement risks were identified. The pharmaceutical patent landscape in Singapore for JAK inhibitors is broadly similar to the landscape observed in Australia and Japan, reflecting the global nature of the relevant patent families. None of the identified third-party patents contain claims that would be infringed by PPC-4187.

Overall Singapore Risk Assessment: LOW.

G. Thailand

W&M identified approximately 15 third-party patent families with potential relevance to PPC-4187 in Thailand. The Thai pharmaceutical patent landscape in the JAK inhibitor space is relatively less crowded than in jurisdictions such as China, Japan, or South Korea, reflecting a smaller volume of patent filings by multinational pharmaceutical companies in Thailand for this class of compounds.

Upon review, no material infringement risks were identified. The third-party patents present in Thailand were principally counterparts of families already analyzed in other jurisdictions and found to be non-infringing.

Overall Thailand Risk Assessment: LOW.

H. Malaysia

W&M identified approximately 12 third-party patent families with potential relevance to PPC-4187 in Malaysia. The patent landscape in Malaysia for JAK inhibitors is comparatively sparse, and the identified families were principally counterparts of families analyzed in other jurisdictions.

Upon review, no material infringement risks were identified.

Overall Malaysia Risk Assessment: LOW.

I. Indonesia

W&M identified approximately 10 third-party patent families with potential relevance to PPC-4187 in Indonesia. Patent filings in the JAK inhibitor space in Indonesia are limited, and the majority of the identified families were counterparts of families already reviewed in other Territory jurisdictions.

Upon review, no material infringement risks were identified.

Overall Indonesia Risk Assessment: LOW.

J. Philippines

W&M identified approximately 8 third-party patent families with potential relevance to PPC-4187 in the Philippines. The intellectual property landscape in the Philippines for the JAK inhibitor / atopic dermatitis therapeutic space is relatively undeveloped from a patent density perspective.

Upon review, no material infringement risks were identified.

Overall Philippines Risk Assessment: LOW.

K. Vietnam

W&M identified approximately 8 third-party patent families with potential relevance to PPC-4187 in Vietnam. The patent landscape in Vietnam for JAK inhibitors is similar to that observed in other ASEAN jurisdictions, with limited patent filings and no material third-party claims directed to compounds or formulations overlapping with PPC-4187.

Upon review, no material infringement risks were identified.

Overall Vietnam Risk Assessment: LOW.

L. Taiwan

Taiwan maintains an active patent examination system administered by the Taiwan intellectual Property Office (TIPO). W&M identified approximately 25 third-party patent families with potential relevance to PPC-4187 in Taiwan.

The most notable third-party patent analyzed was the following:

1. Formosa BioSciences Corp. — TW Patent No. I 789,012 (and related family members). This patent family includes claims directed to oral JAK inhibitor dosage forms, specifically extended-release (modified-release) formulations designed to achieve sustained drug release over an extended period. The independent claims specify extended-release matrix tablets incorporating specific rate-controlling polymers and requiring in vitro dissolution profiles demonstrating less than 30% drug release at two hours and greater than 80% drug release at twelve hours. W&M reviewed PPC-4187's film-coated tablet formulation and confirmed that PPC-4187 is formulated as an immediate-release tablet, not an extended-release formulation. PPC-4187's dissolution profile demonstrates rapid drug release (greater than 85% drug release within 30 minutes in standard dissolution media), which is fundamentally inconsistent with the extended-release dissolution profile required by the Formosa claims. W&M's conclusion: non-infringement; low risk.

The remaining patent families identified in Taiwan were classified as Tier C and did not raise material infringement concerns.

Overall Taiwan Risk Assessment: LOW.

V. CONSOLIDATED RISK ASSESSMENT

Based on the jurisdiction-by-jurisdiction analysis set forth in Section IV, the consolidated FTO risk assessment for PPC-4187 across all twelve jurisdictions in the Licensed Territory is summarized in the table below.

In total, W&M reviewed approximately 340 third-party patent families across all twelve jurisdictions in the Licensed Territory. Of these, approximately 12 families were classified as Tier A (High initial relevance) and approximately 45 families were classified as Tier B (Moderate initial relevance). Following detailed claim construction and infringement analysis, no high-risk patents were identified in any jurisdiction. All Tier A and Tier B families were ultimately assessed as non-infringing for PPC-4187 in its current 25 mg and 50 mg film-coated tablet formulation for the treatment of moderate-to-severe atopic dermatitis in adults.

W&M's overall conclusion, with which we concur, is that the manufacture, use, sale, offer for sale, and importation of PPC-4187 in the Licensed Territory presents a low risk of infringement of identified third-party patent rights.

VI. IMPLICATIONS FOR THE LICENSE AGREEMENT

The favorable FTO risk profile described in this memorandum has several important implications for the Exclusive License Agreement between Penterra and Meridian.

Representations and Warranties. The low FTO risk profile supports Penterra's ability to provide customary representations and warranties regarding non-infringement in the Licensed Territory. The current draft of the Exclusive License Agreement includes a representation by Penterra that, to its knowledge as of the Effective Date, the Licensed intellectual Property does not infringe any valid and enforceable patent rights of any third party in the Licensed Territory. The W&M FTO opinion provides a sound basis for Penterra to make this knowledge-qualified representation with reasonable confidence.

Indemnification. Penterra's intellectual property infringement indemnity obligation under the Exclusive License Agreement requires Penterra to indemnify and hold harmless Meridian and its affiliates from and against losses, damages, liabilities, costs, and expenses (including reasonable attorneys' fees) arising out of any third-party claims that the Licensed intellectual Property as existing on the Effective Date infringes valid and enforceable third-party intellectual property rights in the Licensed Territory. The favorable FTO findings directly support Penterra's ability to assume this indemnity obligation with an appropriate risk assessment.

We note that the indemnification cap for the Exclusive License Agreement has been set at 200% of total payments received by Penterra (with a floor of $36 million based on the $18 million upfront payment to be paid by Meridian upon execution). Importantly, however, the current draft provides that no cap applies to Penterra's indemnification obligation with respect to intellectual property infringement claims. The favorable FTO assessment substantially mitigates Penterra's exposure under this uncapped indemnity provision. Nevertheless, given the uncapped nature of this obligation, we recommend that Penterra continue to monitor the patent landscape in the Licensed Territory on an ongoing basis, as discussed further in Section VIII below.

Joint Patent Committee. The Exclusive License Agreement contemplates the establishment of a Joint Patent Committee comprising two representatives appointed by each party. The Joint Patent Committee will be responsible for, among other things, coordinating patent prosecution, maintenance, and enforcement activities relating to Penterra's patent portfolio in the Licensed Territory. We recommend that FTO monitoring be included as a standing agenda item at the Joint Patent Committee's quarterly meetings, as set forth in our recommendations in Section VIII.

Defensive Patent Portfolio. Penterra's own patent portfolio in the Licensed Territory — including composition-of-matter patents expiring August 12, 2037, and the crystalline Form A patent (with a counterpart U.S. patent expiring November 3, 2038) — provides a strong defensive position. In the event of any third-party patent assertion, Penterra's own patents may serve as a basis for counterclaims or cross-licensing negotiations, further reducing the practical risk to both Penterra and Meridian.

VII. LIMITATIONS AND QUALIFICATIONS

The FTO assessment summarized in this memorandum is subject to the following limitations and qualifications, which should be borne in mind by all recipients:

1. Unpublished Applications. The W&M FTO opinion is based on currently issued patents and published patent applications as of the search cut-off date of August 2023. Patent applications filed within the eighteen-month priority period prior to the cut-off date may not yet have been published and therefore would not have been captured by the patent landscape search. Such unpublished applications may contain claims that, once published and examined, could present infringement risks not addressed in this memorandum. This inherent limitation applies to all FTO analyses and underscores the importance of conducting periodic updates, as recommended in Section VIII.

2. Database Completeness. FTO opinions are inherently limited by the quality and completeness of patent database records. While the major patent offices in the Licensed Territory (including CNIPA, JPO, KIPO, and IP Australia) maintain comprehensive and well-indexed digital databases, the patent registries in certain ASEAN jurisdictions — including Thailand, Indonesia, the Philippines, and Vietnam — may not be fully digitized or may contain incomplete records, particularly for older patent filings. W&M made reasonable efforts to supplement national registry searches with commercial database searches, but the possibility that relevant patents were not identified in these jurisdictions cannot be entirely excluded.

3. Inherent Uncertainty of Claim Construction. Claim construction and infringement analysis necessarily involve the exercise of professional judgment and prediction. The interpretation of patent claims by courts and administrative bodies can be unpredictable, and actual outcomes in litigation or opposition proceedings may differ from the assessments provided in the W&M opinion and this memorandum. This is particularly the case with respect to the application of the doctrine of equivalents, which involves a fact-intensive inquiry that may yield different results depending on the jurisdiction and the specific arguments advanced by the parties.

4. Scope Limited to Patent Rights. The W&M FTO analysis, and this memorandum, address only the risk of infringement of third-party patent rights. The analysis does not cover regulatory data exclusivity, trade secret rights, unfair competition claims, or other non-patent intellectual property rights that may affect the manufacture, use, sale, or importation of PPC-4187 in the Licensed Territory. Penterra and Meridian should ensure that appropriate diligence is conducted on these non-patent intellectual property considerations through separate work streams.

5. Reliance Limitations. The W&M FTO opinion was provided solely for the benefit of Penterra Pharmaceuticals Corp. and Calderwood & Harkness LLP as Penterra's legal counsel. The opinion is not addressed to Meridian, and Meridian may not rely on the W&M opinion without a separate engagement letter or reliance letter from W&M. If Meridian or its counsel (Lam, Cheung & Firth LLP) requests access to the underlying FTO opinion, appropriate arrangements regarding reliance, privilege, and confidentiality will need to be negotiated separately.

6. Formulation and Indication Changes. The FTO assessment is specific to PPC-4187 in its current 25 mg and 50 mg film-coated tablet formulation for the treatment of moderate-to-severe atopic dermatitis in adults. Any material changes to PPC-4187's formulation (e.g., development of a new dosage form, new dosage strength, or alternative delivery mechanism), manufacturing process (e.g., adoption of a different synthetic route), or therapeutic indication (e.g., expansion to pediatric atopic dermatitis, other inflammatory conditions, or combination therapy regimens) would require an updated FTO assessment covering the modified product or indication.

VIII. RECOMMENDATIONS

Based on our review of the W&M FTO opinion and the analysis set forth in this memorandum, we make the following recommendations to the deal team:

1. Periodic FTO Updates. We recommend that W&M be engaged to conduct annual updates to the patent landscape search in the five largest markets within the Licensed Territory — China, Japan, South Korea, Australia, and Taiwan — for the duration of the development and commercialization period for PPC-4187. Annual updates should include searches for newly published patent applications and newly granted patents in the JAK inhibitor / atopic dermatitis therapeutic space, with a particular focus on any new patent families from the patent holders identified in this memorandum (Novagenix Biosciences Ltd., Zenlong Pharma Co., Ltd., Daiho Pharmaceutical Corp., Kitagawa Chemical Industries K.K., Sanwa Pharma K.K., HanVita Biopharma Inc., and Formosa BioSciences Corp.) as well as the patent portfolios of major pharmaceutical companies active in the JAK inhibitor market. Updates for the remaining ASEAN jurisdictions (Singapore, Thailand, Malaysia, Indonesia, the Philippines, and Vietnam) and New Zealand may be conducted on a biennial basis, given the lower patent density in these jurisdictions.

2. Patent Watch Services. We recommend that W&M establish watching briefs for newly published patent applications in the JAK inhibitor / atopic dermatitis space in key Territory jurisdictions. Patent watch services should be configured to provide automatic alerts when new patent applications or grants are published by the national patent offices in China, Japan, South Korea, Australia, and Taiwan that match predefined keyword, classification code, or chemical structure criteria. This will enable early identification of potentially relevant third-party patents and allow Penterra to take timely action, such as filing third-party observations or oppositions, where appropriate.

3. Coordination with Local Counsel. We recommend that the deal team coordinate with Meridian's local counsel, including Nakamura & Takeda Law Offices in Japan, regarding jurisdiction-specific patent linkage and regulatory patent list considerations as PPC-4187 progresses toward regulatory submissions in the Licensed Territory. Japan's patent linkage system, in particular, requires careful coordination between patent prosecution, regulatory submissions, and patent listing on the PMDA registry. Similar considerations may apply in South Korea, where the Korea Ministry of Food and Drug Safety (MFDS) administers a patent linkage system for listed drugs. Early engagement with local counsel on these issues will facilitate a smooth regulatory approval process and maximize the defensive value of Penterra's patent portfolio.

4. Joint Patent Committee Agenda. We recommend that, once the Joint Patent Committee is constituted under the Exclusive License Agreement, FTO monitoring be included as a standing agenda item at the Committee's quarterly meetings. This will ensure that both Penterra and Meridian remain apprised of developments in the patent landscape and can coordinate on any necessary responsive actions, including patent challenges, design-around strategies, or license negotiations with third-party patent holders.

IX. CONCLUSION

Based on Calderwood & Harkness's review of the W&M FTO opinion and our independent analysis of the underlying claim charts, prosecution histories, and relevant patent landscape, we concur with W&M's overall assessment that PPC-4187 (Penteracitinib; PENTECLAR) presents a low risk of infringing third-party patent rights across all twelve jurisdictions in the Licensed Territory. W&M identified and analyzed approximately 340 third-party patent families across the Territory and concluded — and we concur — that none of the identified patents present a high risk of infringement for PPC-4187 in its current 25 mg and 50 mg film-coated tablet formulation for the treatment of moderate-to-severe atopic dermatitis in adults.

This favorable FTO assessment supports proceeding with the out-license of PPC-4187 to Meridian and supports Penterra's provision of customary intellectual property representations, warranties, and indemnification obligations under the Exclusive License Agreement. The assessment should be read in conjunction with the limitations and qualifications set forth in Section VII and the recommendations for ongoing monitoring set forth in Section VIII.

This memorandum is prepared for Calderwood & Harkness's internal use and for the benefit of our client, Penterra Pharmaceuticals Corp., in connection with the PPC-4187 out-license transaction. It is protected by the attorney-client privilege and the attorney work product doctrine and should not be disclosed to any party outside of the authorized distribution list without the prior authorization of Marcus Delgado, Responsible Partner.

PRIVILEGED AND CONFIDENTIAL — ATTORNEY WORK PRODUCT — ATTORNEY-CLIENT PRIVILEGE

Prepared by: Wendy Schultz, Working Associate, Calderwood & Harkness LLP

Reviewed by: Marcus Delgado, Responsible Partner, intellectual Property, Calderwood & Harkness LLP

Distribution limited to the following individuals:

Calderwood & Harkness LLP:

• Marcus Delgado, Responsible Partner

• Catherine Bloom, Senior Associate

• Peter Vassiliev, Associate

• Sylvia Hartwell, Associate

Penterra Pharmaceuticals Corp.:

• Anita M. Fremont, General Counsel

• Dr. Priya Nandakumar, Senior Vice President, intellectual Property

Do not distribute to counterparty (Meridian Bio Therapeutics Limited) or counterparty's counsel (Lam, Cheung & Firth LLP) without prior authorization from Marcus Delgado.

Jurisdiction	Third-Party Families Identified	Risk Level	Key Notes
China (incl. HK/Macau)	~85	Low	Structural differentiation from nearest genus claims; no overlap with formulation or method claims
Japan	~60	Low	Distinct scaffold; doctrine of equivalents analysis negative; local counsel concurs
South Korea	~40	Low	Ring system distinction from closest art (pyrrolo-pyrimidine vs. pyrazolo-pyrimidine)
Australia	~30	Low	No relevant third-party claims identified
New Zealand	~15	Low	No relevant third-party claims identified
Singapore	~20	Low	No relevant third-party claims identified
Thailand	~15	Low	Limited JAK inhibitor patent filings in jurisdiction
Malaysia	~12	Low	No relevant third-party claims identified
Indonesia	~10	Low	Limited patent filings in JAK inhibitor space
Philippines	~8	Low	No relevant third-party claims identified
Vietnam	~8	Low	No relevant third-party claims identified
Taiwan	~25	Low	Extended-release claims do not cover PPC-4187 immediate-release tablet

PRIVILEGED & CONFIDENTIAL ATTORNEY WORK PRODUCT — ATTORNEY-CLIENT PRIVILEGE
MEMORANDUM
September 15, 2023
FROM: Wendy Schultz, Working Associate Calderwood & Harkness LLP 600 Lexington Avenue, 30th Floor New York, NY 10022
TO: Marcus Delgado, Responsible Partner, intellectual Property Calderwood & Harkness LLP
RE: Freedom-to-Operate Summary — Compound PPC-4187 (Penteracitinib) in Licensed Territory
CLIENT: Penterra Pharmaceuticals Corp. ("Penterra" or "PPC")
MATTER: Out-License of PPC-4187 to Meridian Bio Therapeutics Limited ("Meridian")
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I. EXECUTIVE SUMMARY
The purpose of this memorandum is to summarize and analyze the freedom-to-operate ("FTO") opinion provided by Whitford & Cascade Insurance Brokers ("W&M"), Penterra's patent prosecution counsel, for the manufacture, use, sale, offer for sale, and importation of PPC-4187 (proposed International Nonproprietary Name ("INN"): Penteracitinib; proposed trade name: PENTECLAR) across the Licensed Territory defined in the Exclusive License Agreement between Penterra and Meridian Bio Therapeutics Limited ("Meridian"). This memorandum is prepared in connection with Calderwood & Harkness's representation of Penterra in the out-license of PPC-4187 to Meridian and is intended to assist the deal team in assessing intellectual property risk for purposes of structuring and finalizing the Exclusive License Agreement.
The Licensed Territory, as defined in the current draft of the Exclusive License Agreement, comprises the following twelve jurisdictions: the People's Republic of China (including Hong Kong Special Administrative Region and Macau Special Administrative Region), Japan, the Republic of Korea, Australia, New Zealand, Singapore, Thailand, Malaysia, Indonesia, the Philippines, Vietnam, and Taiwan (collectively, the "Licensed Territory" or "Territory").
The W&M FTO opinion was authored by Dr. Alan J. Whitford, Lead Patent Attorney, of Whitford & Cascade Insurance Brokers, 1750 K Street NW, Suite 600, Washington, DC 20006. Dr. Whitford has served as Penterra's lead patent prosecution counsel since the inception of the PPC-4187 patent portfolio in 2018 and possesses extensive familiarity with the compound's chemical structure, mechanism of action, and patent landscape. The W&M opinion, dated August 28, 2023, was delivered to Penterra's General Counsel, Anita M. Fremont, and subsequently provided to Calderwood & Harkness under the common interest privilege for purposes of the out-license transaction.
Overall Conclusion. Based on our review of the W&M FTO opinion and our independent analysis of the underlying claim charts, prosecution histories, and relevant prior art, the overall conclusion is that there is a low risk of infringement of third-party patents in the Licensed Territory for the development, manufacture, and commercialization of PPC-4187 in its current 25 mg and 50 mg film-coated tablet formulation as a selective Janus kinase 1 ("JAK1") inhibitor for the treatment of moderate-to-severe atopic dermatitis in adults. W&M identified no third-party patent that presents a high risk of infringement across any of the twelve jurisdictions comprising the Licensed Territory. While certain third-party patent families were identified as requiring detailed claim construction analysis, in each instance W&M concluded — and we concur — that PPC-4187 does not infringe the relevant claims, whether analyzed under literal infringement or applicable equivalents doctrines.
This favorable FTO assessment supports Penterra's ability to provide customary intellectual property representations, warranties, and indemnification obligations under the Exclusive License Agreement and is an important consideration in the deal team's overall risk assessment for the transaction.
II. BACKGROUND
A. The Compound — PPC-4187
PPC-4187 is a novel, selective Janus kinase 1 (JAK1) inhibitor being developed as an oral, once-daily tablet formulation for the treatment of moderate-to-severe atopic dermatitis in adults. The compound was discovered by Penterra's internal medicinal chemistry team and is designed to achieve high selectivity for JAK1 over JAK2, JAK3, and TYK2, thereby potentially offering an improved safety profile relative to pan-JAK inhibitors currently on the market or in late-stage development.
The proposed International Nonproprietary Name (INN) for PPC-4187 is "Penteracitinib," reflecting the compound's membership in the "-citinib" stem class of JAK inhibitors. Penterra intends to commercialize the compound under the proposed trade name PENTECLAR in both the retained territory (United States and European Union/EEA) and, through its licensee Meridian, in the Licensed Territory.
PPC-4187 is currently in the Phase IIb stage of clinical development. Penterra sponsored and completed Study PPC-4187-201, a randomized, double-blind, placebo-controlled, dose-ranging Phase IIb trial conducted at approximately 75 sites across the United States and the European Union. The study enrolled 420 adult patients with moderate-to-severe atopic dermatitis. Topline results were announced in June 2023 and demonstrated statistically significant improvement in the primary endpoint — the proportion of patients achieving at least a 75% improvement from baseline in the Eczema Area and Severity Index (EASI-75) at Week 16 — compared with placebo (p<0.001 for both the 25 mg and 50 mg dose groups). Secondary endpoints, including IGA 0/1 response and pruritus NRS improvement, also showed statistically significant improvements over placebo. The safety profile observed in the Phase IIb study was consistent with the known class effects of JAK1-selective inhibitors, with no unexpected safety signals identified.
The compound is designated by the internal code PPC-4187. The dosage strengths under development are 25 mg and 50 mg film-coated tablets for oral administration. The chemistry, manufacturing, and controls (CMC) package for PPC-4187 has been validated, with manufacturing of both drug substance and drug product conducted at Alkerra Manufacturing Inc., located at 5200 Meridian Parkway, Research Triangle Park, NC 27713. Alkerra serves as Penterra's contract manufacturing organization and has been qualified under current Good Manufacturing Practice (cGMP) standards. The manufacturing process is the subject of certain of Penterra's proprietary patent filings, as described in Section II.B below.
B. Penterra's Own IP Portfolio
Penterra has developed a robust intellectual property portfolio around PPC-4187, comprising seven patent families that collectively cover composition of matter, crystalline forms (including the commercial Form A polymorph), methods of use for the treatment of atopic dermatitis and other JAK1-mediated inflammatory conditions, pharmaceutical formulation (including the film-coated tablet), and the manufacturing process for drug substance synthesis.
The following key granted patents in the Licensed Territory are relevant to the FTO analysis and to the overall IP landscape being licensed to Meridian:
• CN Patent No. ZL 2020 1 0456789.0 — Composition of Matter. Granted by the China National intellectual Property Administration (CNIPA). Covers the PPC-4187 compound per se, including pharmaceutically acceptable salts and solvates thereof. Expiration date: August 12, 2037.
• JP Patent No. 7,012,345 — Composition of Matter. Granted by the Japan Patent Office (JPO). Covers the PPC-4187 compound per se and pharmaceutical compositions containing the same. Expiration date: August 12, 2037.
• KR Patent No. 10-2345678 — Composition of Matter. Granted by the Korean intellectual Property Office (KIPO). Covers the PPC-4187 compound and methods of preparing the same. Expiration date: August 12, 2037.
• AU Patent No. 2020234567 — Composition of Matter. Granted by IP Australia. Covers the PPC-4187 compound per se. Expiration date: August 12, 2037.
National phase entries from PCT/US2019/045123 (the foundational PCT application covering PPC-4187 composition of matter) have been filed and are either granted or pending in Japan, China, the Republic of Korea, Australia, Singapore, and six ASEAN countries within the Licensed Territory. Prosecution in Singapore, Thailand, Malaysia, Indonesia, the Philippines, and Vietnam is ongoing, with no material prior art rejections received to date.
For portfolio context, though the United States and the European Union are within Penterra's retained territory, we note the following U.S. patents:
• U.S. Patent No. 11,234,567 — Composition of Matter. Covers the PPC-4187 compound per se, pharmaceutically acceptable salts, and pharmaceutical compositions. Expiration date: August 12, 2037.
• U.S. Patent No. 11,345,678 — Crystalline Form A. Covers the crystalline Form A polymorph of PPC-4187, characterized by specific X-ray powder diffraction (XRPD) peaks. Expiration date: November 3, 2038.
The proposed trade name PENTECLAR has been filed as a trademark application in China, Hong Kong SAR, Japan, the Republic of Korea, Australia, and additional Territory jurisdictions. In the United States, PENTECLAR has been registered as U.S. Trademark Registration No. 6,789,012. Trademark clearance in the Licensed Territory is being handled separately by Calderwood & Harkness's trademark group and is not addressed in this FTO memorandum.
C. Scope of W&M FTO Analysis
W&M was engaged by Penterra in March 2023 to conduct comprehensive patent landscape searches and FTO analysis across all twelve jurisdictions comprising the Licensed Territory. The engagement was structured to provide Penterra with an assessment of the risk that the development, manufacture, use, sale, offer for sale, and importation of PPC-4187 in the Licensed Territory would infringe valid and enforceable third-party patent rights.
The scope of W&M's analysis covered the following five technical categories:
(i) Composition of matter / active ingredient — claims directed to the PPC-4187 compound per se or to genera of compounds within which PPC-4187 might fall;
(ii) Crystalline polymorphs — claims directed to specific crystalline forms of JAK inhibitors, including crystalline forms that might overlap with Penterra's commercial Form A polymorph;
(iii) Pharmaceutical formulations — claims directed to oral solid dosage forms, film-coated tablets, or specific excipient combinations relevant to PPC-4187's finished drug product;
(iv) Methods of treatment — claims directed to the use of JAK inhibitors, JAK1-selective inhibitors, or specific compounds for the treatment of atopic dermatitis, inflammatory skin conditions, or related JAK1-mediated disorders; and
(v) Manufacturing processes — claims directed to synthetic routes, intermediate compounds, or process conditions relevant to the manufacture of PPC-4187 drug substance.
W&M consulted the patent registries and databases maintained by each national patent office within the Licensed Territory, including CNIPA (China), JPO (Japan), KIPO (Republic of Korea), IP Australia, IPONZ (New Zealand), IPOS (Singapore), DIP Thailand, MyIPO (Malaysia), DGIP Indonesia, IPOPHL (Philippines), NOIP (Vietnam), and TIPO (Taiwan). In addition, W&M conducted searches using WIPO PATENTSCOPE to identify PCT applications designating any of the foregoing jurisdictions. Commercial patent databases, including Pemberton Data Systems, Orbit intelligence, and Marlowe Solutions, were also utilized to supplement the national registry searches and to identify patent family relationships across jurisdictions.
The cut-off date for the prior art search was August 2023. W&M acknowledges, and we concur, that patent applications filed within the eighteen-month priority period prior to the search cut-off date may not yet have been published and therefore would not be captured by the search.
In total, W&M reviewed approximately 340 third-party patent families identified as potentially relevant across the Licensed Territory. The identification, classification, and analysis of these families is described in greater detail in Sections III and IV below.
III. METHODOLOGY
W&M employed a multi-layered search methodology designed to maximize coverage and minimize the risk of overlooking relevant third-party patent rights. The methodology comprised three principal search approaches, which were applied across all twelve jurisdictions in the Licensed Territory.
Keyword Searches. W&M conducted keyword searches using terms related to PPC-4187's chemical name, proposed INN (penteracitinib), mechanism of action (JAK1 inhibitor, Janus kinase inhibitor, selective JAK inhibitor), therapeutic indication (atopic dermatitis, eczema, inflammatory skin disease, dermatitis), and formulation characteristics (film-coated tablet, oral solid dosage form, immediate-release tablet). Keyword searches were conducted in English and, where applicable, in the local language of the relevant jurisdiction (Mandarin Chinese for CNIPA, Japanese for JPO, Korean for KIPO, and Traditional Chinese for TIPO). W&M engaged local language specialists to assist with the non-English keyword searches to ensure comprehensive coverage.
Structure-Based Searches. W&M conducted chemical substructure searches using the Markush structure of PPC-4187 and its key structural motifs, including the pyrazole ring system, the core heterocyclic scaffold, and the acylamino substituent. These structure-based searches were designed to identify third-party patents claiming genera of compounds that might encompass PPC-4187 or close structural analogs. The structure searches were conducted using Pemberton Data Systems's chemical structure search module and STN/Fenmore Health IT.
Classification Code Searches. W&M supplemented the keyword and structure-based searches with searches based on International Patent Classification (IPC) and Cooperative Patent Classification (CPC) codes relevant to JAK inhibitors (e.g., C07D class codes for heterocyclic compounds; A61K 31/ codes for pharmaceutical compositions containing nitrogen heterocycles; A61P 17/00 for dermatological agents).
Risk Tier Classification. Following identification, the approximately 340 third-party patent families were classified into three risk tiers:
(A) High — Close structural or functional overlap with PPC-4187; claims that, on their face, might be construed to encompass the PPC-4187 compound, formulation, or method of use; requiring detailed claim construction and infringement analysis.
(B) Moderate — Tangential overlap with PPC-4187; claims that touch upon the same general technical space (JAK inhibitors, atopic dermatitis treatments) but that, upon initial review, appear distinguishable; requiring detailed claim analysis to confirm non-infringement.
(C) Low — Peripheral relevance only; claims directed to structurally distinct compounds, different formulation types, or unrelated methods of treatment; easily designed around or clearly non-infringed.
Of the approximately 340 families identified, W&M classified approximately 12 families as Tier A (High), approximately 45 families as Tier B (Moderate), and the remaining approximately 283 families as Tier C (Low). Each Tier A and Tier B family was subjected to detailed claim construction analysis, including review of the claims as granted (or as published, in the case of pending applications), the patent specification, the prosecution history (where available), and relevant prior art. Claim charts were prepared for each Tier A family and for selected Tier B families.
Claim Construction Approach. W&M applied jurisdiction-specific claim construction standards in analyzing third-party patent claims, recognizing that the approach to claim interpretation varies across the Licensed Territory. In particular:
• China: W&M applied the CNIPA Patent Examination Guidelines and relevant Supreme People's Court judicial interpretations regarding patent claim construction, including the principle that claims should be interpreted in light of the specification and drawings but are not limited thereto. W&M also considered the applicability of the doctrine of equivalents under Chinese patent law.
• Japan: W&M applied the JPO Examination Guidelines for Patent and Utility Model and relevant case law from the intellectual Property High Court, including the five-factor test for the doctrine of equivalents established in the Supreme Court's Ball Spline Bearing decision (1998). W&M engaged Nakamura & Takeda Law Offices in Tokyo to provide local counsel input on the application of the Japanese doctrine of equivalents and on Pharmaceuticals and Medical Devices Agency (PMDA) regulatory patent linkage considerations relevant to PPC-4187.
• Republic of Korea: W&M applied KIPO claim construction standards, including the Korean Supreme Court's framework for interpreting patent claims in light of the specification and prosecution history.
• Australia: W&M applied the principles of purposive construction as articulated by the High Court of Australia and the Federal Court, interpreting claims by reference to the specification as a whole and the understanding of the person skilled in the art.
• Other Territory Jurisdictions: For jurisdictions with less developed patent jurisprudence in the pharmaceutical space (e.g., certain ASEAN jurisdictions), W&M applied general principles of patent claim construction consistent with the applicable national patent law and, where available, relevant administrative guidelines.
W&M's methodology is consistent with industry best practices for pharmaceutical FTO analyses and, in our view, was thorough and appropriately comprehensive for the purposes of the Penterra/Meridian out-license transaction.
IV. JURISDICTION-BY-JURISDICTION FTO ANALYSIS
The following sections summarize W&M's FTO findings for each of the twelve jurisdictions in the Licensed Territory. For each jurisdiction, we identify the number of third-party patent families reviewed, highlight the most noteworthy third-party patents analyzed, summarize W&M's conclusions, and provide an overall risk assessment.
A. People's Republic of China (Including Hong Kong SAR and Macau SAR)
China represents the largest single market within the Licensed Territory for PPC-4187 and, accordingly, was the subject of the most extensive patent landscape search. W&M identified approximately 85 third-party patent families with potential relevance to PPC-4187 in China. Of these, seven families were classified as Tier A (High) or Tier B (Moderate) and were subjected to detailed claim construction analysis.
The following third-party patents were among the most closely analyzed:
1. Novagenix Biosciences Ltd. — CN Patent No. ZL 2017 1 0892345.6 (and related family members). This patent family includes claims directed to a broad genus of JAK inhibitor compounds characterized by a substituted pyrrolo-pyrimidine core scaffold. The genus is defined by a Markush structure with multiple variable substituents. W&M conducted a detailed structural comparison of PPC-4187 against the genus definition and concluded that PPC-4187 falls outside the claimed genus due to specific structural differentiation at the pyrazole moiety. The Novagenix claims require a fused bicyclic ring system at the R2 position that is absent from PPC-4187's structure. Moreover, the Novagenix patent specification contains no disclosure of PPC-4187 or any compound structurally analogous thereto, and the prosecution history reflects that the applicant narrowed the claims during prosecution in response to prior art rejections. W&M's conclusion: non-infringement; low risk.
2. Zenlong Pharma Co., Ltd. — CN Patent No. ZL 2019 1 0345678.2 (and related family members). This patent family includes claims directed to pharmaceutical formulations of JAK1-selective inhibitors in the form of oral solid dosage forms. The independent claims specify the use of particular excipient combinations, including hydroxypropyl methylcellulose acetate succinate (HPMCAS) as a matrix-forming polymer and specific disintegrant ratios. W&M reviewed PPC-4187's film-coated tablet formulation in detail and determined that PPC-4187 does not utilize HPMCAS or the specific excipient combinations recited in the Zenlong claims. The formulation of PPC-4187 employs different excipients, including microcrystalline cellulose as the principal filler and croscarmellose sodium as the disintegrant, in ratios and combinations not covered by the Zenlong claims. W&M's conclusion: non-infringement; low risk.
3. Daiho Pharmaceutical Corp. — CN Patent No. ZL 2018 1 0567890.3 (and related family members). This patent family includes claims directed to methods of treating inflammatory skin conditions, including atopic dermatitis, using a combination therapy comprising a JAK inhibitor and a topical corticosteroid administered concurrently. The independent method claims expressly require the co-administration of both a JAK inhibitor and a topical corticosteroid. Because PPC-4187 is being developed as a monotherapy — and Penterra's current clinical development program does not contemplate mandatory co-administration with a topical corticosteroid — the Daiho method claims are not practiced by the manufacture, sale, or use of PPC-4187 as a monotherapy for moderate-to-severe atopic dermatitis. W&M's conclusion: non-infringement; low risk. W&M noted, however, that if Penterra or Meridian were to pursue a combination therapy indication requiring co-administration with a topical corticosteroid, the Daiho patent family would require re-evaluation.
The remaining patent families identified in China were classified as Tier C (Low) and, upon review, were determined to be directed to structurally distinct compounds, unrelated formulation types, or methods of treatment for conditions other than atopic dermatitis. None of these families raised material infringement concerns for PPC-4187.
Overall China Risk Assessment: LOW.
We note that Penterra's own CN Patent No. ZL 2020 1 0456789.0 provides strong composition-of-matter protection for PPC-4187 in China through August 12, 2037. This patent provides Penterra (and, through the license, Meridian) with an affirmative right to exclude third parties from making, using, selling, or importing PPC-4187 in China and serves as a significant defensive asset in any potential patent dispute.
With respect to Hong Kong SAR and Macau SAR, W&M confirmed that the patent landscape is substantially similar to that of mainland China for purposes of this analysis. Hong Kong operates a re-registration system for short-term patents and a standard patent system based on grants from designated patent offices (including CNIPA). Macau's patent system relies on registration of patents granted by certain designated offices. W&M identified no additional third-party patent risks specific to Hong Kong or Macau beyond those analyzed for mainland China.
B. Japan
Japan represents the second-largest single market within the Licensed Territory and has a well-developed pharmaceutical patent landscape with robust examination and enforcement mechanisms. W&M identified approximately 60 third-party patent families with potential relevance to PPC-4187 in Japan. Of these, three families were classified as Tier A and subjected to detailed claim construction analysis, with input from Nakamura & Takeda Law Offices in Tokyo.
The following third-party patents were among the most closely analyzed:
1. Kitagawa Chemical Industries K.K. — JP Patent No. 6,890,123 (and related family members). This patent family includes claims directed to heteroaryl JAK inhibitors defined by a substituted pyridazine core scaffold with various heterocyclic substituents. W&M conducted a detailed comparison of PPC-4187's core scaffold against the Kitagawa claims and concluded that PPC-4187 is structurally distinct. Specifically, PPC-4187 features a pyrazolo-pyrimidine core, which differs from the pyridazine core recited in the Kitagawa claims in both ring size and heteroatom positioning. W&M further analyzed the claims under the five-factor doctrine of equivalents test articulated by the Japanese Supreme Court and concluded that PPC-4187 would not be found to infringe under the doctrine of equivalents. The structural differences between PPC-4187 and the claimed genus are not merely insubstantial variations but reflect fundamental differences in the core ring system that would be recognized by a person skilled in the art as resulting in different pharmacological properties and binding characteristics. Nakamura & Takeda Law Offices concurred in this assessment. W&M's conclusion: non-infringement under both literal and equivalents analysis; low risk.
2. Sanwa Pharma K.K. — JP Patent No. 6,945,678 (and related family members). This patent family includes claims directed to specific crystalline forms of JAK inhibitor compounds, characterized by X-ray powder diffraction (XRPD) patterns with enumerated peak positions and relative intensities. W&M compared the XRPD data for Penterra's commercial Form A polymorph against the crystalline form claims in the Sanwa patent and determined that the claimed crystalline forms exhibit distinct XRPD patterns that do not overlap with Penterra's Form A. Specifically, the Sanwa claims require characteristic XRPD peaks at 2θ values of 8.2°, 14.7°, 19.1°, and 22.6° (±0.2°), whereas Penterra's Form A exhibits characteristic peaks at 2θ values of 7.5°, 12.3°, 17.8°, and 24.1° (±0.2°). The claimed polymorphs are directed to different compounds entirely (substituted imidazopyridine JAK inhibitors) and the crystalline forms are of a different chemical entity. W&M's conclusion: non-infringement; low risk.
The remaining patent families identified in Japan were classified as Tier B or Tier C and, upon analysis, were determined to present no material infringement risk for PPC-4187. Several families were directed to second-generation JAK inhibitor compounds with distinct structural scaffolds, and others were directed to combination therapy methods not practiced by PPC-4187 monotherapy.
Overall Japan Risk Assessment: LOW.
Penterra's JP Patent No. 7,012,345 (composition of matter) provides strong protection for PPC-4187 in Japan through August 12, 2037. W&M, in coordination with Nakamura & Takeda Law Offices, also considered the implications of the Japanese patent linkage system administered by the PMDA in connection with the listing of patents on the PMDA's patent information registry (the so-called "Orange Book" equivalent). Penterra's composition-of-matter patent is expected to be listed on the PMDA registry upon regulatory approval of PPC-4187 in Japan, which will provide an additional layer of patent protection against generic entry.
C. Republic of Korea
South Korea is a significant market within the Licensed Territory, with well-developed pharmaceutical patent examination and enforcement regimes. W&M identified approximately 40 third-party patent families with potential relevance to PPC-4187 in the Republic of Korea. Of these, two families were classified as Tier A or Tier B and subjected to detailed claim construction analysis.
The most notable third-party patent analyzed was the following:
1. HanVita Biopharma Inc. — KR Patent No. 10-1987654 (and related family members). This patent family includes claims directed to substituted pyrrolo-pyrimidine JAK inhibitors for the treatment of inflammatory and autoimmune diseases. The independent claims define a genus of compounds using a Markush structure centered on a pyrrolo[2,3-d]pyrimidine ring system. Upon initial review, this patent family was classified as Tier A due to the superficial structural similarity between the pyrrolo-pyrimidine scaffold recited in the HanVita claims and PPC-4187's core heterocyclic framework.
However, upon detailed claim construction analysis, W&M concluded that PPC-4187 does not satisfy all claim limitations of the HanVita patent. Specifically, the HanVita claims require a pyrrolo[2,3-d]pyrimidine ring system with a specific substitution pattern at the C-4 and N-7 positions that is absent from PPC-4187's structure. PPC-4187 employs a pyrazolo[1,5-a]pyrimidine ring system — a different heterocyclic framework with different connectivity, ring fusion, and heteroatom positioning. The distinction between the pyrrolo[2,3-d]pyrimidine and pyrazolo[1,5-a]pyrimidine ring systems is well-recognized in the medicinal chemistry literature and would be understood by a person skilled in the art as representing a fundamental structural difference, not an insubstantial variation. W&M assessed this as a low-to-moderate risk upon initial classification but, following detailed analysis, ultimately concluded that PPC-4187 is non-infringing of the HanVita claims. We concur in this assessment.
The remaining patent families identified in South Korea were classified as Tier C and did not raise material infringement concerns.
Overall Korea Risk Assessment: LOW.
Penterra's KR Patent No. 10-2345678 (composition of matter) provides protection for PPC-4187 in the Republic of Korea through August 12, 2037.
D. Australia
Australia maintains a well-established pharmaceutical patent examination and enforcement system administered by IP Australia and the Federal Court of Australia. W&M identified approximately 30 third-party patent families with potential relevance to PPC-4187 in Australia.
Upon review, no third-party patents were identified with claims that would be infringed by PPC-4187's composition, formulation, or use. The patent families identified in Australia were largely counterparts of families already analyzed in the context of other Territory jurisdictions (principally China and Japan), and the conclusions reached for those jurisdictions applied equally to the Australian counterparts. Several Australian patent families directed to JAK inhibitor compounds were reviewed and found to claim structurally distinct compounds with no overlap with PPC-4187.
Overall Australia Risk Assessment: LOW.
Penterra's AU Patent No. 2020234567 provides composition-of-matter protection for PPC-4187 in Australia through August 12, 2037. Australia's patent term extension regime under the Patents Act 1990 (Cth) may provide an opportunity for patent term extension for AU Patent No. 2020234567 upon regulatory approval of PPC-4187 by the Therapeutic Goods Administration (TGA), subject to eligibility requirements.
E. New Zealand
New Zealand follows a patent framework that is broadly similar to Australia's, and its pharmaceutical patent landscape overlaps substantially with Australia's. W&M identified approximately 15 third-party patent families with potential relevance to PPC-4187 in New Zealand. Many of these families were counterparts of the same families reviewed in the Australian analysis.
Upon review, no material infringement risks were identified. The third-party patent families present in New Zealand were directed to structurally distinct JAK inhibitor compounds, unrelated formulation types, or methods of treatment for non-dermatological indications.
Overall New Zealand Risk Assessment: LOW.
Penterra's national phase application from PCT/US2019/045123 is pending in New Zealand, and prosecution is proceeding without material objections.
F. Singapore
Singapore maintains a well-organized patent system administered by the intellectual Property Office of Singapore (IPOS). Penterra's national phase entry from PCT/US2019/045123 has been filed in Singapore and is currently pending. W&M identified approximately 20 third-party patent families with potential relevance to PPC-4187 in Singapore.
Upon review, no material infringement risks were identified. The pharmaceutical patent landscape in Singapore for JAK inhibitors is broadly similar to the landscape observed in Australia and Japan, reflecting the global nature of the relevant patent families. None of the identified third-party patents contain claims that would be infringed by PPC-4187.
Overall Singapore Risk Assessment: LOW.
G. Thailand
W&M identified approximately 15 third-party patent families with potential relevance to PPC-4187 in Thailand. The Thai pharmaceutical patent landscape in the JAK inhibitor space is relatively less crowded than in jurisdictions such as China, Japan, or South Korea, reflecting a smaller volume of patent filings by multinational pharmaceutical companies in Thailand for this class of compounds.
Upon review, no material infringement risks were identified. The third-party patents present in Thailand were principally counterparts of families already analyzed in other jurisdictions and found to be non-infringing.
Overall Thailand Risk Assessment: LOW.
H. Malaysia
W&M identified approximately 12 third-party patent families with potential relevance to PPC-4187 in Malaysia. The patent landscape in Malaysia for JAK inhibitors is comparatively sparse, and the identified families were principally counterparts of families analyzed in other jurisdictions.
Upon review, no material infringement risks were identified.
Overall Malaysia Risk Assessment: LOW.
I. Indonesia
W&M identified approximately 10 third-party patent families with potential relevance to PPC-4187 in Indonesia. Patent filings in the JAK inhibitor space in Indonesia are limited, and the majority of the identified families were counterparts of families already reviewed in other Territory jurisdictions.
Upon review, no material infringement risks were identified.
Overall Indonesia Risk Assessment: LOW.
J. Philippines
W&M identified approximately 8 third-party patent families with potential relevance to PPC-4187 in the Philippines. The intellectual property landscape in the Philippines for the JAK inhibitor / atopic dermatitis therapeutic space is relatively undeveloped from a patent density perspective.
Upon review, no material infringement risks were identified.
Overall Philippines Risk Assessment: LOW.
K. Vietnam
W&M identified approximately 8 third-party patent families with potential relevance to PPC-4187 in Vietnam. The patent landscape in Vietnam for JAK inhibitors is similar to that observed in other ASEAN jurisdictions, with limited patent filings and no material third-party claims directed to compounds or formulations overlapping with PPC-4187.
Upon review, no material infringement risks were identified.
Overall Vietnam Risk Assessment: LOW.
L. Taiwan
Taiwan maintains an active patent examination system administered by the Taiwan intellectual Property Office (TIPO). W&M identified approximately 25 third-party patent families with potential relevance to PPC-4187 in Taiwan.
The most notable third-party patent analyzed was the following:
1. Formosa BioSciences Corp. — TW Patent No. I 789,012 (and related family members). This patent family includes claims directed to oral JAK inhibitor dosage forms, specifically extended-release (modified-release) formulations designed to achieve sustained drug release over an extended period. The independent claims specify extended-release matrix tablets incorporating specific rate-controlling polymers and requiring in vitro dissolution profiles demonstrating less than 30% drug release at two hours and greater than 80% drug release at twelve hours. W&M reviewed PPC-4187's film-coated tablet formulation and confirmed that PPC-4187 is formulated as an immediate-release tablet, not an extended-release formulation. PPC-4187's dissolution profile demonstrates rapid drug release (greater than 85% drug release within 30 minutes in standard dissolution media), which is fundamentally inconsistent with the extended-release dissolution profile required by the Formosa claims. W&M's conclusion: non-infringement; low risk.
The remaining patent families identified in Taiwan were classified as Tier C and did not raise material infringement concerns.
Overall Taiwan Risk Assessment: LOW.
V. CONSOLIDATED RISK ASSESSMENT
Based on the jurisdiction-by-jurisdiction analysis set forth in Section IV, the consolidated FTO risk assessment for PPC-4187 across all twelve jurisdictions in the Licensed Territory is summarized in the table below.
In total, W&M reviewed approximately 340 third-party patent families across all twelve jurisdictions in the Licensed Territory. Of these, approximately 12 families were classified as Tier A (High initial relevance) and approximately 45 families were classified as Tier B (Moderate initial relevance). Following detailed claim construction and infringement analysis, no high-risk patents were identified in any jurisdiction. All Tier A and Tier B families were ultimately assessed as non-infringing for PPC-4187 in its current 25 mg and 50 mg film-coated tablet formulation for the treatment of moderate-to-severe atopic dermatitis in adults.
W&M's overall conclusion, with which we concur, is that the manufacture, use, sale, offer for sale, and importation of PPC-4187 in the Licensed Territory presents a low risk of infringement of identified third-party patent rights.
VI. IMPLICATIONS FOR THE LICENSE AGREEMENT
The favorable FTO risk profile described in this memorandum has several important implications for the Exclusive License Agreement between Penterra and Meridian.
Representations and Warranties. The low FTO risk profile supports Penterra's ability to provide customary representations and warranties regarding non-infringement in the Licensed Territory. The current draft of the Exclusive License Agreement includes a representation by Penterra that, to its knowledge as of the Effective Date, the Licensed intellectual Property does not infringe any valid and enforceable patent rights of any third party in the Licensed Territory. The W&M FTO opinion provides a sound basis for Penterra to make this knowledge-qualified representation with reasonable confidence.
Indemnification. Penterra's intellectual property infringement indemnity obligation under the Exclusive License Agreement requires Penterra to indemnify and hold harmless Meridian and its affiliates from and against losses, damages, liabilities, costs, and expenses (including reasonable attorneys' fees) arising out of any third-party claims that the Licensed intellectual Property as existing on the Effective Date infringes valid and enforceable third-party intellectual property rights in the Licensed Territory. The favorable FTO findings directly support Penterra's ability to assume this indemnity obligation with an appropriate risk assessment.
We note that the indemnification cap for the Exclusive License Agreement has been set at 200% of total payments received by Penterra (with a floor of $36 million based on the $18 million upfront payment to be paid by Meridian upon execution). Importantly, however, the current draft provides that no cap applies to Penterra's indemnification obligation with respect to intellectual property infringement claims. The favorable FTO assessment substantially mitigates Penterra's exposure under this uncapped indemnity provision. Nevertheless, given the uncapped nature of this obligation, we recommend that Penterra continue to monitor the patent landscape in the Licensed Territory on an ongoing basis, as discussed further in Section VIII below.
Joint Patent Committee. The Exclusive License Agreement contemplates the establishment of a Joint Patent Committee comprising two representatives appointed by each party. The Joint Patent Committee will be responsible for, among other things, coordinating patent prosecution, maintenance, and enforcement activities relating to Penterra's patent portfolio in the Licensed Territory. We recommend that FTO monitoring be included as a standing agenda item at the Joint Patent Committee's quarterly meetings, as set forth in our recommendations in Section VIII.
Defensive Patent Portfolio. Penterra's own patent portfolio in the Licensed Territory — including composition-of-matter patents expiring August 12, 2037, and the crystalline Form A patent (with a counterpart U.S. patent expiring November 3, 2038) — provides a strong defensive position. In the event of any third-party patent assertion, Penterra's own patents may serve as a basis for counterclaims or cross-licensing negotiations, further reducing the practical risk to both Penterra and Meridian.
VII. LIMITATIONS AND QUALIFICATIONS
The FTO assessment summarized in this memorandum is subject to the following limitations and qualifications, which should be borne in mind by all recipients:
1. Unpublished Applications. The W&M FTO opinion is based on currently issued patents and published patent applications as of the search cut-off date of August 2023. Patent applications filed within the eighteen-month priority period prior to the cut-off date may not yet have been published and therefore would not have been captured by the patent landscape search. Such unpublished applications may contain claims that, once published and examined, could present infringement risks not addressed in this memorandum. This inherent limitation applies to all FTO analyses and underscores the importance of conducting periodic updates, as recommended in Section VIII.
2. Database Completeness. FTO opinions are inherently limited by the quality and completeness of patent database records. While the major patent offices in the Licensed Territory (including CNIPA, JPO, KIPO, and IP Australia) maintain comprehensive and well-indexed digital databases, the patent registries in certain ASEAN jurisdictions — including Thailand, Indonesia, the Philippines, and Vietnam — may not be fully digitized or may contain incomplete records, particularly for older patent filings. W&M made reasonable efforts to supplement national registry searches with commercial database searches, but the possibility that relevant patents were not identified in these jurisdictions cannot be entirely excluded.
3. Inherent Uncertainty of Claim Construction. Claim construction and infringement analysis necessarily involve the exercise of professional judgment and prediction. The interpretation of patent claims by courts and administrative bodies can be unpredictable, and actual outcomes in litigation or opposition proceedings may differ from the assessments provided in the W&M opinion and this memorandum. This is particularly the case with respect to the application of the doctrine of equivalents, which involves a fact-intensive inquiry that may yield different results depending on the jurisdiction and the specific arguments advanced by the parties.
4. Scope Limited to Patent Rights. The W&M FTO analysis, and this memorandum, address only the risk of infringement of third-party patent rights. The analysis does not cover regulatory data exclusivity, trade secret rights, unfair competition claims, or other non-patent intellectual property rights that may affect the manufacture, use, sale, or importation of PPC-4187 in the Licensed Territory. Penterra and Meridian should ensure that appropriate diligence is conducted on these non-patent intellectual property considerations through separate work streams.
5. Reliance Limitations. The W&M FTO opinion was provided solely for the benefit of Penterra Pharmaceuticals Corp. and Calderwood & Harkness LLP as Penterra's legal counsel. The opinion is not addressed to Meridian, and Meridian may not rely on the W&M opinion without a separate engagement letter or reliance letter from W&M. If Meridian or its counsel (Lam, Cheung & Firth LLP) requests access to the underlying FTO opinion, appropriate arrangements regarding reliance, privilege, and confidentiality will need to be negotiated separately.
6. Formulation and Indication Changes. The FTO assessment is specific to PPC-4187 in its current 25 mg and 50 mg film-coated tablet formulation for the treatment of moderate-to-severe atopic dermatitis in adults. Any material changes to PPC-4187's formulation (e.g., development of a new dosage form, new dosage strength, or alternative delivery mechanism), manufacturing process (e.g., adoption of a different synthetic route), or therapeutic indication (e.g., expansion to pediatric atopic dermatitis, other inflammatory conditions, or combination therapy regimens) would require an updated FTO assessment covering the modified product or indication.
VIII. RECOMMENDATIONS
Based on our review of the W&M FTO opinion and the analysis set forth in this memorandum, we make the following recommendations to the deal team:
1. Periodic FTO Updates. We recommend that W&M be engaged to conduct annual updates to the patent landscape search in the five largest markets within the Licensed Territory — China, Japan, South Korea, Australia, and Taiwan — for the duration of the development and commercialization period for PPC-4187. Annual updates should include searches for newly published patent applications and newly granted patents in the JAK inhibitor / atopic dermatitis therapeutic space, with a particular focus on any new patent families from the patent holders identified in this memorandum (Novagenix Biosciences Ltd., Zenlong Pharma Co., Ltd., Daiho Pharmaceutical Corp., Kitagawa Chemical Industries K.K., Sanwa Pharma K.K., HanVita Biopharma Inc., and Formosa BioSciences Corp.) as well as the patent portfolios of major pharmaceutical companies active in the JAK inhibitor market. Updates for the remaining ASEAN jurisdictions (Singapore, Thailand, Malaysia, Indonesia, the Philippines, and Vietnam) and New Zealand may be conducted on a biennial basis, given the lower patent density in these jurisdictions.
2. Patent Watch Services. We recommend that W&M establish watching briefs for newly published patent applications in the JAK inhibitor / atopic dermatitis space in key Territory jurisdictions. Patent watch services should be configured to provide automatic alerts when new patent applications or grants are published by the national patent offices in China, Japan, South Korea, Australia, and Taiwan that match predefined keyword, classification code, or chemical structure criteria. This will enable early identification of potentially relevant third-party patents and allow Penterra to take timely action, such as filing third-party observations or oppositions, where appropriate.
3. Coordination with Local Counsel. We recommend that the deal team coordinate with Meridian's local counsel, including Nakamura & Takeda Law Offices in Japan, regarding jurisdiction-specific patent linkage and regulatory patent list considerations as PPC-4187 progresses toward regulatory submissions in the Licensed Territory. Japan's patent linkage system, in particular, requires careful coordination between patent prosecution, regulatory submissions, and patent listing on the PMDA registry. Similar considerations may apply in South Korea, where the Korea Ministry of Food and Drug Safety (MFDS) administers a patent linkage system for listed drugs. Early engagement with local counsel on these issues will facilitate a smooth regulatory approval process and maximize the defensive value of Penterra's patent portfolio.
4. Joint Patent Committee Agenda. We recommend that, once the Joint Patent Committee is constituted under the Exclusive License Agreement, FTO monitoring be included as a standing agenda item at the Committee's quarterly meetings. This will ensure that both Penterra and Meridian remain apprised of developments in the patent landscape and can coordinate on any necessary responsive actions, including patent challenges, design-around strategies, or license negotiations with third-party patent holders.
IX. CONCLUSION
Based on Calderwood & Harkness's review of the W&M FTO opinion and our independent analysis of the underlying claim charts, prosecution histories, and relevant patent landscape, we concur with W&M's overall assessment that PPC-4187 (Penteracitinib; PENTECLAR) presents a low risk of infringing third-party patent rights across all twelve jurisdictions in the Licensed Territory. W&M identified and analyzed approximately 340 third-party patent families across the Territory and concluded — and we concur — that none of the identified patents present a high risk of infringement for PPC-4187 in its current 25 mg and 50 mg film-coated tablet formulation for the treatment of moderate-to-severe atopic dermatitis in adults.
This favorable FTO assessment supports proceeding with the out-license of PPC-4187 to Meridian and supports Penterra's provision of customary intellectual property representations, warranties, and indemnification obligations under the Exclusive License Agreement. The assessment should be read in conjunction with the limitations and qualifications set forth in Section VII and the recommendations for ongoing monitoring set forth in Section VIII.
This memorandum is prepared for Calderwood & Harkness's internal use and for the benefit of our client, Penterra Pharmaceuticals Corp., in connection with the PPC-4187 out-license transaction. It is protected by the attorney-client privilege and the attorney work product doctrine and should not be disclosed to any party outside of the authorized distribution list without the prior authorization of Marcus Delgado, Responsible Partner.
PRIVILEGED AND CONFIDENTIAL — ATTORNEY WORK PRODUCT — ATTORNEY-CLIENT PRIVILEGE
Prepared by: Wendy Schultz, Working Associate, Calderwood & Harkness LLP
Reviewed by: Marcus Delgado, Responsible Partner, intellectual Property, Calderwood & Harkness LLP
Distribution limited to the following individuals:
Calderwood & Harkness LLP:
• Marcus Delgado, Responsible Partner
• Catherine Bloom, Senior Associate
• Peter Vassiliev, Associate
• Sylvia Hartwell, Associate
Penterra Pharmaceuticals Corp.:
• Anita M. Fremont, General Counsel
• Dr. Priya Nandakumar, Senior Vice President, intellectual Property
Do not distribute to counterparty (Meridian Bio Therapeutics Limited) or counterparty's counsel (Lam, Cheung & Firth LLP) without prior authorization from Marcus Delgado.
Jurisdiction | Third-Party Families Identified | Risk Level | Key Notes
China (incl. HK/Macau) | ~85 | Low | Structural differentiation from nearest genus claims; no overlap with formulation or method claims
Japan | ~60 | Low | Distinct scaffold; doctrine of equivalents analysis negative; local counsel concurs
South Korea | ~40 | Low | Ring system distinction from closest art (pyrrolo-pyrimidine vs. pyrazolo-pyrimidine)
Australia | ~30 | Low | No relevant third-party claims identified
New Zealand | ~15 | Low | No relevant third-party claims identified
Singapore | ~20 | Low | No relevant third-party claims identified
Thailand | ~15 | Low | Limited JAK inhibitor patent filings in jurisdiction
Malaysia | ~12 | Low | No relevant third-party claims identified
Indonesia | ~10 | Low | Limited patent filings in JAK inhibitor space
Philippines | ~8 | Low | No relevant third-party claims identified
Vietnam | ~8 | Low | No relevant third-party claims identified
Taiwan | ~25 | Low | Extended-release claims do not cover PPC-4187 immediate-release tablet

PRIVILEGED & CONFIDENTIAL ATTORNEY WORK PRODUCT — ATTORNEY-CLIENT PRIVILEGE

MEMORANDUM

I. EXECUTIVE SUMMARY

II. BACKGROUND

III. METHODOLOGY

IV. JURISDICTION-BY-JURISDICTION FTO ANALYSIS

V. CONSOLIDATED RISK ASSESSMENT

VI. IMPLICATIONS FOR THE LICENSE AGREEMENT

VII. LIMITATIONS AND QUALIFICATIONS

VIII. RECOMMENDATIONS

IX. CONCLUSION

Record

Parties

Dates

Amounts