This Rilonacept Drug Asset Due Diligence Report was built with PatSnap Life Sciences MCP workflows. Drug & Asset MCP establishes identity, ownership and stage; Clinical Trials MCP checks design, endpoints and readouts; Company & Deal Intelligence MCP reconstructs transaction precedent. Explore the MCP servers used in this report.
Decision date: 15 July 2026. Currency fields are presented in US$ millions as returned by the deal dataset. This is a screening memorandum, not legal, medical, patent or investment advice.
Approved
Highest phase
24
Registered trials
41
Result records
3
Matched deals
Advance diligence: development maturity and available evidence support continued investment, subject to indication-specific safety, IP, and commercial gates.
The central underwriting question is whether Rilonacept can convert its Fc fusion protein profile and IL-1α x IL-1β biology into clinically meaningful differentiation while preserving an investable safety, IP and commercial position.
| Asset | Rilonacept (query alias: rilonacept) |
|---|---|
| Modality / target | Fc fusion protein; IL-1α x IL-1β; IL-1α inhibitors, IL-1β inhibitors |
| Highest global status | Approved |
| Originator | Regeneron Pharmaceuticals, Inc. |
| Active developers | Hangzhou Zhongmeihuadong Pharmaceutical Co., Ltd., Jubilant HollisterStier LLC, Kiniksa Pharmaceuticals (UK) Ltd. |
The MCP disease footprint includes Muckle-Wells Syndrome, Recurrent pericarditis, Deficiency of Interleukin-1 Receptor Antagonist. The highest-phase flag is a useful orientation point, but the licensing case depends on indication-level evidence and rights, not the global label alone.
| Registry | Phase | Status | Enrollment | Lead primary endpoint |
|---|---|---|---|---|
| NCT03737110 | Phase 3 | Completed | 86 | Time to Pericarditis Recurrence in the RW Period |
| NCT06660732 | Phase 2 | Recruiting | 60 | Change in number of segments with fluorodeoxyglucose F18 (FDG) uptake on cardiac fluorodeoxyglucose F18 - positron emission tomography (FDG-PET) scan |
| NCT03980522 | Phase 2 | Completed | 26 | Parts 1, 2 and 4: Pretreatment C-Reactive Protein (CRP) Levels |
The trial set should be diligenced for randomization, comparator relevance, endpoint hierarchy, analysis population, multiplicity, geographic mix and readout timing. For early-stage studies, safety and dose selection can be as decision-critical as response rate.

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Not Applicable; n=23; evaluation: Positive. Reported fields: Adverse Event: continuous chest pain = One patient discontinued the treatment due to continuous chest pain not related to pericarditis
Not Applicable; n=not disclosed; evaluation: not stated. Reported fields: Disease duration = 48 month ( 41 - 56)
Not Applicable; n=not disclosed; evaluation: not stated. Reported fields: Ability to wean off steroids = 1 month ( 1 - 9)
These fields are structured evidence signals, not a substitute for statistical review. The next diligence pass should reconcile denominators, confidence intervals, follow-up, censoring, dose cohorts and treatment-emergent toxicity against the original abstract, registry and protocol.
Rilonacept addresses Muckle-Wells Syndrome, Recurrent pericarditis, Deficiency of Interleukin-1 Receptor Antagonist. Commercial attractiveness rests on addressable biomarker-positive patients, treatment-line placement, duration, administration burden, pricing and displacement of entrenched standards. The modality—Fc fusion protein—must demonstrate a benefit large enough to offset class-specific safety and operational costs.
The strongest market-validation signal in this screen is partner behavior: 3 matched transaction record(s) indicate that sophisticated counterparties have assigned strategic value to the asset or its rights. That does not establish net present value; probability of success, remaining R&D spend, royalties, cost sharing and territorial scope still need modeling.
| Date | Transaction | Phase at deal | Disclosed economics |
|---|---|---|---|
| 2022-02-21 | Hangzhou Zhongmei will collaborate with Kiniksa to develop and market Arcalyst and mavrilimumab in the Asia Pacific Region, which encompasses Greater China, South Korea, Australia, and 18 other countries (excluding Japan). | Approved | US$22.0M upfront; US$640.0M milestones; US$662.0M stated total |
| 2017-09-25 | LICENSE AGREEMENT By and Between REGENERON PHARMACEUTICALS, INC. and KINIKSA PHARMACEUTICALS, LTD. | Approved | Financial terms not disclosed |
| 2016-09-14 | Neovii to commercialize Regeneron’s Arcalyst outside USA and Japan | Approved | Financial terms not disclosed |
Headline values are not directly comparable. Diligence should normalize upfront cash, equity, development and sales milestones, tiered royalties, opt-in mechanics, cost sharing, change-of-control clauses and geography.
No asset-specific patent-application milestone appeared in the returned milestone slice. That absence is not a freedom-to-operate conclusion; a dedicated family, claim, ownership, expiry, and legal-status search remains mandatory before signing.
The claim chart should separately test composition or sequence coverage, formulation and dosing, indication and biomarker claims, combinations, manufacturing know-how, prosecution history, term extensions and third-party blocking rights. Confirm that licensed patents, data and know-how track every granted territory and field.
Cross-functional diligence should also test CMC comparability, supply chain, pharmacovigilance, regulatory correspondence, data integrity, investigator concentration, partner obligations and change-of-control restrictions.
Advance diligence: development maturity and available evidence support continued investment, subject to indication-specific safety, IP, and commercial gates.
Required pre-signing gates: reproduce key efficacy analyses; complete an indication-specific safety review; run a full patent-family and freedom-to-operate search; model risk-adjusted economics by territory; and reconcile all rights, sublicenses and encumbrances.
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Data provenance: PatSnap Drug & Asset MCP, Clinical Trials MCP, and Company & Deal Intelligence MCP; accessed 15 July 2026. Counts and status fields may change as source records update.