Sean,
I wanted to get you up to speed on a new engagement that just went live this morning. We're representing Solstice Biomedical Devices Ltd. (Irish parent) and its U.S. subsidiary, Solstice Biomedical Inc., in connection with a traditional 510(k) submission for their Solstice Lumina™ CGM System — which consists of the Lumina C14 implantable sensor and the Lumina R7 wearable reader/transmitter, submitted as a single system. The engagement reference is 1037-00002; Miriam Calloway is the responsible partner and Joel Strauss is the billing partner. The Lumina system is already CE-marked in the EU (EU MDR CE Certificate No. MCA-2024-07319, issued September 12, 2024 by Meridian Conformity Assessment GmbH, NB 0483) and has been commercially available in Europe since last fall, but has no existing FDA clearance or approval. Solstice does have prior FDA interaction history — they obtained 510(k) clearance for an earlier-generation product, the GlucoStrip RX-200 Test Strip Reader (K192847, cleared November 14, 2019, product code NBW) — but the Lumina system represents a significant technology evolution and will require its own predicate analysis under a different product code. The retainer ($75,000) was received today, so we are fully engaged and need to move quickly given the Pre-Sub timeline I'll lay out below.
I have three research assignments for you. Let me walk through each one.
**Assignment #1: Predicate Device Clearance History for Product Code QKQ**
I need you to compile a comprehensive list of all 510(k) clearances under product code QKQ (Electrode, Glucose, Subcutaneous) from the FDA's 510(k) database. The client has identified two NovaSense Medical Technologies Inc. devices as predicates, and these should be the focus of your deepest analysis:
- **Primary Predicate:** NovaSense GlucoTrack NX-500 CGM System, 510(k) No. K211034, cleared June 18, 2022. Product code QKQ, Class II. Key characteristics: 10-day sensor wear duration, enzymatic electrochemical sensor, BLE transmission to a handheld reader.
- **Secondary Predicate (Reference Device):** NovaSense GlucoTrack NX-700 CGM System, 510(k) No. K230489, cleared March 7, 2024. Product code QKQ, Class II. Key characteristics: 14-day sensor wear, enhanced BLE 5.0 transmission, updated algorithm.
For both K211034 and K230489, pull the full 510(k) summaries from the FDA database. I need you to review and catalog the stated intended use/indications for use, the technological characteristics sections, and — critically — the predicate chains (i.e., what predicates did NovaSense itself cite in each submission?). Understanding how NovaSense built its own substantial equivalence arguments will be important for framing ours.
Also pull any other recent QKQ clearances so we can understand the competitive landscape and how FDA has been evaluating substantial equivalence arguments in this device space more broadly.
One important note: the GlucoStrip RX-200 (K192847) is product code NBW, not QKQ. We're citing it only for corporate pedigree and to show the client's prior FDA interaction history — it is not a predicate for substantial equivalence purposes for this submission.
For background context, NovaSense is headquartered at 4800 Innovation Parkway, San Diego, CA 92121; FY2024 revenue approximately $1.24 billion; CEO David Reinhardt; VP Regulatory Affairs Dr. Karen Nishimura. There is no formal dispute or litigation with NovaSense at this time — I just want you to have the corporate picture as you research their clearance history.
**Assignment #2: Recent CDRH Decisions on CGM Devices**
I'd like you to survey recent CDRH decisions — last two to three years — relating to continuous glucose monitoring devices, covering both 510(k) clearances and De Novo classifications. Pay particular attention to the iCGM (integrated continuous glucose monitoring) classification pathway under De Novo classification order DEN170088 and the applicable special controls associated with that pathway.
Make sure to review the FDA guidance document "Integrated Continuous Glucose Monitoring Systems" (September 2023). I'm especially interested in how that guidance addresses MARD requirements (the target is ≤ 9.0% overall) and consensus error grid requirements (≥ 99% of paired data points in Clarke Error Grid Zones A+B).
Key questions to answer: Have other CGM manufacturers successfully used the NovaSense GlucoTrack devices as predicates? If so, how did FDA handle differences in sensor wear duration, electrode materials, and algorithms? This will directly inform how we frame Solstice's differences from the NX-500 and NX-700.
This research will feed into both our device classification analysis memo and Miriam's separate analysis of whether Solstice should pursue standard 510(k) versus iCGM classification. Miriam is planning a separate memo on the iCGM special controls analysis, but your survey will provide essential groundwork for both.
**Assignment #3: March 2024 Reclassification Order Under 21 C.F.R. § 862.1355**
FDA issued a reclassification order effective March 2024 affecting the glucose test system regulation at 21 C.F.R. § 862.1355. I need you to locate and analyze that order in detail: what changed, what special controls were added or modified, and how this impacts the classification rationale for the Lumina CGM System.
In particular, assess whether the reclassification order affects the predicate device analysis. The primary predicate (K211034) was cleared in June 2022, before the reclassification. The secondary predicate (K230489) was cleared in March 2024, contemporaneous with the reclassification. Does the reclassification change the regulatory basis for substantial equivalence arguments referencing either device? Confirm that the anticipated device class remains Class II and the anticipated regulation number remains 21 C.F.R. § 862.1355. This analysis is critical for the device classification memo.
**How This All Fits Together**
Your research will feed directly into two key deliverables:
First, the **Device Classification Analysis Memo**. You and I will jointly prepare this memo analyzing product code QKQ, 21 C.F.R. § 862.1355, the Class II classification rationale, and the impact of the March 2024 reclassification order. Your research will form the factual backbone. I want to have a working draft to Miriam for review by the week of May 19.
Second, the **Pre-Sub Meeting Package**. The Pre-Sub meeting request must be submitted to FDA (CDRH, OHT2–Division of Chemistry and Toxicology Devices) by June 2, 2025, and the full meeting package — with the 60-day advance submission requirement — by June 16, 2025, targeting an August 14, 2025 meeting date. Your predicate research will directly inform the "Predicate Comparison and Substantial Equivalence Discussion" section of the Pre-Sub package.
On the technical side, Pinnacle Regulatory Consulting Group LLC (Dr. Sandra Ellison and Thomas Greenbaum, based in Rockville, MD) is preparing the technical summaries, performance testing protocols, and biocompatibility assessments. We'll need to coordinate with them, but the legal analysis of classification and predicate selection is squarely our responsibility.
I also want to flag that we need to be mindful of freedom-to-operate considerations with respect to NovaSense's patent portfolio — specifically U.S. Patent Nos. 10,847,221; 11,234,567; and 11,502,893. Crestline IP Advisory LLC (Dr. Raymond Cho) is handling the FTO analysis, and their preliminary assessment (dated April 10, 2025) flagged low-to-moderate risk regarding U.S. 10,847,221 (an enzyme coating patent). That's a separate workstream, but we should be aware of the predicate device manufacturer's IP position as we frame our substantial equivalence arguments. I'll forward the Crestline preliminary assessment summary separately once I confirm privilege handling with Miriam.
**Key Technical Details to Keep in Mind**
As you work through the predicate analysis, there are five key differences between the Lumina system and the primary predicate (K211034, NX-500) that will be central to the substantial equivalence argument:
1. **Sensor wear duration:** 14 days (Lumina C14) vs. 10 days (NX-500). Note the secondary predicate NX-700 also has 14-day wear, which helps bridge this gap. 2. **Electrode material:** Platinum-iridium with PtIr-4G proprietary coating (Lumina) vs. platinum (NX-500). 3. **BLE version:** 5.2 (Lumina) vs. 5.0 (NX-500). 4. **Reader form factor:** Arm-worn integrated reader/transmitter (Lumina R7) vs. handheld receiver (NX-500). 5. **Algorithm:** Solstice proprietary glucose prediction algorithm ("LuminaPredict v2.1") vs. NovaSense algorithm.
Performance specifications to note: measurement range 40–400 mg/dL; warm-up time ≤ 60 minutes; alert latency ≤ 5 minutes; sensor functional life 336 hours (14 days × 24 hours). Software versions are Lumina Firmware v3.4.2 (C14 sensor), Lumina Reader OS v2.1.0 (R7 reader), LuminaPredict Algorithm v2.1, and Lumina Mobile App v1.0.3. Again, this is intended as a traditional 510(k) — not De Novo, not PMA — with both C14 and R7 submitted as a single system.
**Deadlines**
- **Friday, May 9, 2025:** First draft of the predicate clearance history compilation (Assignment #1) and the reclassification order analysis (Assignment #3). - **Wednesday, May 14, 2025:** CDRH decisions survey (Assignment #2).
I'll use your research to begin drafting the device classification analysis memo, with the goal of having a working draft to Miriam by the week of May 19.
**Logistics**
All work should be billed to client matter 1037-00002 (Solstice Biomedical Inc.). Please track your time carefully — we are billing hourly against an estimated $650,000 total engagement, and the expense cap without prior client approval is $15,000 for disbursements. Your rate is $475/hr. Please save all documents to the matter file on the firm's DMS as you go.
For background on the full scope and billing arrangements, take a look at the engagement letter dated April 22, 2025. I'm also building a predicate device comparison table (still a work in progress) and a regulatory timeline and milestone tracker with the critical path dates — I'll share both with you shortly.
**Next Steps**
Happy to discuss any of this over a call or feel free to stop by my office. I'd suggest we plan to touch base with Miriam later this week once you've had a chance to start pulling materials and we have a better sense of what the QKQ clearance landscape looks like.
This is a priority engagement — the client team (Dr. Niamh Tierney, VP of Regulatory Affairs, and Marcus Hale, VP of U.S. Operations) is eager to move quickly given the Pre-Sub timeline, so the sooner we can get the foundational research in place, the better.
Thanks, Sean. Looking forward to working on this one with you.
Best,
Amy
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Amy Whitfield Associate, Healthcare & Life Sciences Calderwood & Harkness LLP 1401 K Street NW, Suite 900 Washington, D.C. 20005 awhitfield@calderwoodharkness.com
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