Rilonacept

Name: Rilonacept: FDA records
Creator: Arca

Treats Cryopyrin-Associated Periodic Syndromes (CAPS) … Muckle-Wells Syndrome (MWS). Sold as Arcalyst. Every FDA application for this active ingredient.

As of Nov 14, 2026, FDA lists 1 application for Rilonacept (sold as Arcalyst), first approved Feb 27, 2008, with 2 new uses approved and 0 published complete response letters.

First approved: Feb 27, 2008
Applications: 1
New uses approved: 2
Complete response letters: 0
Medicare spending, 2025: $185M
Orphan exclusivity until: Mar 18, 2028
First approved in the EU: Oct 23, 2009

Medicare Spending

CMS Part D and Part B, 2025, before manufacturer rebates; matched by generic name

Product	Part	Spending, 2025	Change	Beneficiaries
Arcalyst	Part D	$185M	+247%	992

Orphan Designations (FDA)

4 designations, 2 approved for the designated use; see all orphan designations

Treatment of pericarditisKiniksa Pharmaceuticals, Ltd. · designated Jul 14, 2020 · approved Mar 18, 2021 · exclusive to Mar 18, 2028
Treatment of deficiency of interleukin-1 receptor antagonist (DIRA)Regeneron Pharmaceuticals, Inc. · designated May 9, 2017
Treatment of familial Mediterranean feverPhilip J Hashkes, MD, MSc. · designated Jan 9, 2013
Treatment of CIAS1-Associated Periodic SyndromesRegeneron Pharmaceuticals, Inc. · designated Dec 20, 2004 · approved Feb 27, 2008

Approvals in the EU (EMA)

First approved in the EU 20 months after the US. Centrally authorised medicines, matched by ingredient; see all EU approvals

Rilonacept Regeneron (previously Arcalyst), new substanceRegeneron UK Limited · Oct 23, 2009 · withdrawn

Clinical Trials

1 open or ongoing study names this ingredient as an intervention, including as a comparator; newest first. See all

Study	Phase	Status	Posted
Rilonacept in Subjects With Cardiac SarcoidosisCardiac Sarcoidosis · Mayo Clinic	Phase 2	Recruiting	Oct 28, 2024

Applications

NDAs, BLAs and generic ANDAs for this ingredient, oldest first; each opens its full history

Approved	Application	Sponsor	Supplements	Marketing
Feb 27, 2008	ArcalystBLA 125249 · New molecular entity	Kiniksa Pharmaceuticals (Uk), Ltd.	5	Marketed

Applications, approvals and products come from FDA's Drugs@FDA data files, refreshed weekly, grouped by active ingredient as FDA spells it. Complete response letters are FDA's published letters. Medicare spending is CMS's Part D and Part B dashboard, matched to this ingredient by generic name; shortages are FDA's shortage list, matched by application number; clinical trials are ClinicalTrials.gov studies naming the ingredient as an intervention, refreshed daily; safety programs are FDA's REMS list, matched by application number or, for shared programs, by ingredient. Drugs@FDA