Last updated: September 1, 2026
Anakinra is a mature interleukin-1 inhibitor marketed primarily as Kineret by Swedish Orphan Biovitrum AB, or Sobi. Its commercial profile differs from most biologics: rheumatoid arthritis is no longer the main growth driver, while rare inflammatory diseases, Still's disease, neonatal-onset multisystem inflammatory disease, and COVID-19-related use have shaped demand. Kineret remains commercially important to Sobi, but its long-term growth depends on specialty indications, geographic expansion, supply reliability, and the timing of biosimilar or competing IL-1 therapies.
What is anakinra and who markets Kineret?
Anakinra is a recombinant nonglycosylated version of the human interleukin-1 receptor antagonist. It blocks signaling from interleukin-1 alpha and interleukin-1 beta. Kineret is administered by subcutaneous injection, generally at 100 mg once daily in adult rheumatoid arthritis and several autoinflammatory indications.
Amgen developed and originally commercialized Kineret. Sobi obtained exclusive commercial rights outside the United States and Canada in 2018 and acquired global rights, including North America, in 2020. The transaction transferred Kineret and a broader portfolio of rare-disease assets to Sobi and made the product a larger contributor to Sobi's specialty-care business (Sobi, 2020).
| Item |
Anakinra / Kineret |
| Active ingredient |
Anakinra |
| Drug class |
Recombinant interleukin-1 receptor antagonist |
| Original U.S. approval |
November 2001 |
| Original U.S. indication |
Moderately to severely active rheumatoid arthritis |
| U.S. sponsor |
Sobi, following the Amgen transaction |
| Main delivery form |
100 mg prefilled syringe |
| Administration |
Subcutaneous injection |
| Key specialty uses |
CAPS, NOMID, Still's disease, rheumatoid arthritis |
| U.S. regulatory category |
Biologic license application product |
| Primary commercial risk |
Mature product erosion and future biosimilar competition |
What are the main FDA-approved indications for anakinra?
Kineret's value has shifted toward diseases with limited treatment options and low patient counts. These indications support higher persistence and specialty-pharmacy economics than the original rheumatoid arthritis market.
Rheumatoid arthritis
The FDA approved Kineret for moderately to severely active rheumatoid arthritis in adults who have failed one or more disease-modifying antirheumatic drugs. The product competes with tumor necrosis factor inhibitors, JAK inhibitors, IL-6 inhibitors, abatacept, and rituximab.
Anakinra has a weaker commercial position in rheumatoid arthritis than it had at launch. Physicians generally have many alternatives, and Kineret's daily injection creates a burden relative to longer-acting biologics.
Cryopyrin-associated periodic syndromes
Kineret is used for neonatal-onset multisystem inflammatory disease, or NOMID, and other cryopyrin-associated periodic syndromes. These conditions are rare, severe, and driven by excessive IL-1 signaling. Patients can require long-term treatment, producing a more defensible specialty market than rheumatoid arthritis.
Still's disease
The FDA expanded Kineret's label for adult-onset Still's disease and systemic juvenile idiopathic arthritis in 2020. Still's disease is an important commercial use because it aligns with anakinra's rapid IL-1 blockade and specialist prescribing base.
COVID-19
The FDA did not grant Kineret a broad permanent COVID-19 approval. The European Medicines Agency authorized an indication in adults with COVID-19 pneumonia requiring supplemental oxygen who are at risk of developing severe respiratory failure, based on evidence of elevated soluble urokinase plasminogen activator receptor levels (European Medicines Agency, 2022).
COVID-19 created temporary demand and clinical visibility but did not establish a durable revenue base. Hospital utilization, treatment guidelines, and changing COVID-19 epidemiology limited the commercial persistence of this opportunity.
How much revenue does Kineret generate for Sobi?
Kineret is one of Sobi's largest products, but Sobi's public reporting does not always provide a complete, globally standardized product-level revenue history for every reporting period. Public annual reports indicate that Kineret revenue is measured in the multibillion-Swedish-krona range and represents a material share of Sobi's total sales.
Sobi reported total revenue of approximately SEK 18.6 billion in 2023, with growth driven across its hematology and immunology portfolio. Kineret remained a major immunology product, although product mix, currency movements, market access, and COVID-related demand affected year-to-year performance (Sobi, 2024).
| Financial driver |
Effect on Kineret |
| Rare-disease demand |
Supports price and treatment persistence |
| Rheumatoid arthritis competition |
Limits volume growth |
| COVID-19 use |
Produced episodic demand rather than durable growth |
| Daily injection |
Reduces convenience versus longer-acting biologics |
| Specialty distribution |
Supports controlled dispensing and reimbursement management |
| Currency exposure |
Creates volatility in Sobi's reported SEK revenue |
| U.S. rights acquisition |
Increased Sobi's revenue base and commercial responsibility |
| Biosimilar entry |
Would pressure price, access, and net sales |
Kineret's financial trajectory is best characterized as mature and cash-generative rather than high-growth. The product can maintain value through rare-disease demand even as its broader immunology market matures. Revenue expansion is more likely to come from price, market access, and incremental indication penetration than from large increases in treated patients.
What is the competitive landscape for anakinra?
Anakinra competes in two separate markets: broad autoimmune disease and rare autoinflammatory disease.
Broad autoimmune competition
In rheumatoid arthritis, principal competitors include:
- Adalimumab products, including Humira and biosimilars
- Etanercept and biosimilars
- Infliximab and biosimilars
- Tocilizumab
- Sarilumab
- Abatacept
- Rituximab
- JAK inhibitors such as tofacitinib, baricitinib, upadacitinib, and filgotinib where approved
These products have longer dosing intervals, greater physician familiarity, or stronger guideline positioning. Kineret's clinical advantage is its direct IL-1 mechanism and rapid onset in selected inflammatory syndromes, not broad market share.
IL-1 competition
The most relevant IL-1 competitors are:
| Product |
Active ingredient |
Commercial position |
| Kineret |
Anakinra |
Daily IL-1 receptor antagonist with broadest anakinra experience |
| Ilaris |
Canakinumab |
Long-acting IL-1 beta inhibitor with rare-disease indications |
| Arcalyst |
Rilonacept |
Long-acting IL-1 trap, particularly relevant in recurrent pericarditis and CAPS |
| Colchicine and corticosteroids |
Non-biologic alternatives |
Important in selected autoinflammatory and pericarditis settings |
Canakinumab and rilonacept offer less frequent dosing, a significant convenience advantage. Anakinra remains differentiated by its short half-life, which can be useful when clinicians want rapid treatment adjustment or interruption.
When does anakinra lose exclusivity?
Anakinra's core composition-of-matter and early regulatory exclusivity periods have expired. The commercial question is no longer whether the original molecule is protected by a long-lived basic patent. It is whether regulatory, manufacturing, formulation, device, and indication-specific barriers delay practical competition.
The original Kineret patent estate was associated with recombinant interleukin-1 receptor antagonist technology and related production claims. Key early U.S. patents reached the end of their ordinary patent terms around the early 2020s, depending on patent, terminal disclaimers, patent-term adjustment, and regulatory extensions. Kineret therefore has substantially less fundamental exclusivity than newer biologics launched with patent terms extending into the 2030s.
| Exclusivity layer |
Current commercial effect |
| Basic molecule and recombinant protein claims |
Largely expired or near expiration |
| FDA biologic exclusivity |
Expired for the 2001 approval |
| Orphan-drug exclusivity |
Applies only to specific qualifying indications and periods |
| Pediatric exclusivity |
Historical, indication-specific, and expired |
| Formulation and device claims |
Potentially relevant but narrower |
| Manufacturing claims |
Can raise development and scale-up costs |
| Method-of-use patents |
May affect selected indications but usually do not block all uses |
Patent expiration should not be treated as an automatic generic launch date. A biosimilar applicant must establish analytical similarity, manufacturing comparability, clinical support where required, and an acceptable interchangeability or substitution strategy. Patent litigation and settlement terms can also affect launch timing.
What is the Orange Book and Purple Book status of Kineret?
Kineret is a biologic, so its biologic exclusivity and biosimilar competition are tracked primarily through the FDA Purple Book rather than the Orange Book. The Orange Book is principally used for approved small-molecule drug products and listed patents under the Hatch-Waxman framework.
For Kineret, relevant competitive questions include:
- Whether a biosimilar applicant files under the Public Health Service Act section 351(k).
- Whether Sobi lists relevant patents in the Purple Book-related patent process.
- Whether the applicant provides a patent notice and triggers litigation.
- Whether the parties settle on a delayed launch date.
- Whether pharmacy substitution is available under an FDA interchangeability designation.
The absence of a conventional Orange Book patent listing does not mean that Kineret has no enforceable intellectual property. It means that the principal legal pathway is biologic patent litigation rather than the small-molecule Paragraph IV system.
Are there Paragraph IV challenges to anakinra?
A conventional Paragraph IV challenge applies to an abbreviated new drug application, or ANDA, for a small-molecule drug. Kineret is regulated as a biologic, so a biosimilar applicant generally uses the 351(k) pathway rather than filing a Paragraph IV ANDA.
As a result, the relevant competitive event is a biosimilar application and associated patent notice, not a standard Paragraph IV certification. Publicly available information through the established Kineret commercial period does not show a major U.S. biosimilar launch comparable to the adalimumab or trastuzumab markets.
Are anakinra biosimilars approved in the United States or Europe?
The U.S. market has not experienced broad commercial biosimilar penetration for anakinra comparable to major anti-TNF products. The European market has a more active pathway for follow-on biologics, but competition depends on national reimbursement, reference-product designation, manufacturing capacity, and regulatory approvals.
A future anakinra biosimilar would likely face less clinical development risk than a novel biologic because anakinra has a well-characterized mechanism and extensive post-market experience. The commercial hurdle would be price and scale. Rare-disease patient populations may not support many competitors, while rheumatoid arthritis offers volume but carries heavy payer pressure.
What would a biosimilar launch do to Kineret revenue?
The likely effect would be a two-stage erosion pattern:
- Initial impact in price-sensitive autoimmune markets.
- Slower erosion in rare diseases where physician familiarity, continuity of supply, and patient support remain important.
An interchangeable biosimilar could accelerate substitution in the United States. A non-interchangeable product would depend more heavily on payer formulary placement and prescriber switching.
What formulation and manufacturing patents protect anakinra?
Kineret's commercial defensibility is more likely to depend on formulation, device, and manufacturing know-how than on a surviving basic molecule patent.
Potential barriers include:
- Protein stability during storage and shipping
- Control of aggregation and particulates
- Pre-filled syringe compatibility
- Container-closure integrity
- Sterile manufacturing and aseptic filling
- Cell-line and fermentation process control
- Purification and impurity removal
- Analytical methods for potency and comparability
- Cold-chain distribution
These protections can increase the cost and time required to reproduce the product, but they do not necessarily prevent biosimilar approval. A biosimilar applicant can develop a non-infringing process and demonstrate similarity without copying the originator's manufacturing method.
The daily prefilled-syringe presentation is also a commercial weakness relative to long-acting IL-1 competitors. Device improvements could protect patient retention, but they would not create the same exclusivity as a new active ingredient.
What patent litigation and settlement risks affect Kineret?
The key litigation risk is not a broad challenge to a valid composition patent. It is targeted litigation over later-expiring claims involving formulation, dosing, delivery devices, manufacturing processes, or specific methods of treatment.
Potential settlement outcomes include:
| Settlement structure |
Commercial consequence |
| Early license |
Biosimilar enters before full patent expiration |
| Delayed launch |
Preserves branded revenue until an agreed date |
| Narrow indication carve-out |
Allows competition for unprotected uses |
| Royalty-bearing license |
Reduces net price erosion but preserves some revenue |
| No settlement |
Creates launch uncertainty and litigation expense |
Publicly disclosed Kineret-specific settlement terms have not created a market-standard launch date equivalent to the widely reported settlements for major anti-TNF products. The absence of a prominent settlement does not eliminate future litigation risk.
How strong is the anakinra patent estate?
Kineret has a moderate-to-weak long-term patent estate when measured against newer biologics. Its strengths are regulatory experience, rare-disease positioning, manufacturing know-how, and physician familiarity. Its weaknesses are old launch vintage, expired core exclusivity, daily administration, and competition from longer-acting IL-1 inhibitors.
| Patent-estate factor |
Assessment |
| Core molecule protection |
Weak due to age and expiration |
| Indication protection |
Moderate in selected rare diseases |
| Formulation protection |
Potentially moderate, claim-specific |
| Device protection |
Potentially moderate but narrow |
| Manufacturing barriers |
Meaningful operational barrier |
| Regulatory exclusivity |
Historical, not a long-term defense |
| Biosimilar vulnerability |
Moderate, increasing over time |
| Rare-disease commercial moat |
Stronger than in rheumatoid arthritis |
What is the geographic coverage and commercial outlook for anakinra?
Kineret has commercial exposure across the United States and European markets, with additional availability subject to local approvals, reimbursement, and distribution arrangements. The United States is strategically important because of higher biologic pricing and Sobi's ownership of North American rights. Europe provides a broad rare-disease base but generally applies more aggressive health-technology assessment and price controls.
The commercial outlook has four components:
- Stable specialty demand. NOMID, CAPS, Still's disease, and related autoinflammatory uses support recurring treatment.
- Limited rheumatoid arthritis growth. Competition and mature treatment algorithms restrict expansion.
- Indication volatility. COVID-19-related use is not a reliable long-term revenue engine.
- Future price pressure. Biosimilars and payer negotiations could reduce net sales even if patient volume remains stable.
Kineret is therefore more valuable as a durable specialty product than as a high-growth biologic. Its cash-flow profile depends on maintaining rare-disease access and limiting substitution in markets where the clinical need is less price-sensitive.
How does anakinra compare with canakinumab and rilonacept?
| Attribute |
Anakinra |
Canakinumab |
Rilonacept |
| Brand |
Kineret |
Ilaris |
Arcalyst |
| Target |
IL-1 receptor |
IL-1 beta |
IL-1 cytokine trap |
| Dosing |
Usually daily |
Often monthly or less frequent |
Weekly |
| Convenience |
Lower |
Higher |
Higher than anakinra |
| Short-term reversibility |
Strong |
Limited |
Moderate |
| Rare-disease fit |
Strong |
Strong |
Strong |
| Manufacturing maturity |
High |
High |
High |
| Biosimilar exposure |
Increasing long-term risk |
Later patent protection in many uses |
Product-specific |
| Commercial weakness |
Injection burden and mature IP |
High price and narrower use |
High price and indication concentration |
Anakinra's principal clinical-commercial advantage is flexibility. Its principal commercial disadvantage is administration frequency.
Key Takeaways
- Anakinra is a mature biologic marketed as Kineret by Sobi.
- Revenue is concentrated in specialty immunology and rare autoinflammatory diseases rather than rheumatoid arthritis.
- Kineret remains financially material to Sobi, with annual sales in the multibillion-Swedish-krona range.
- Core molecule exclusivity is substantially eroded, making future biosimilar competition the main long-term risk.
- Kineret is governed through the biologic and Purple Book framework, not a conventional Orange Book Paragraph IV process.
- Formulation, device, manufacturing, and method-of-use claims may delay competition but are narrower than core composition patents.
- Canakinumab and rilonacept offer dosing-convenience advantages, while anakinra retains value through rapid onset and reversibility.
- The most likely financial trajectory is stable-to-declining mature-product revenue, moderated by rare-disease demand and specialty pricing.
FAQs
What company owns Kineret?
Swedish Orphan Biovitrum AB, or Sobi, owns and commercializes global Kineret rights following transactions with Amgen completed between 2018 and 2020.
Is anakinra a biosimilar?
No. Kineret is the reference biologic. A biosimilar would need to demonstrate similarity to the reference product through the applicable FDA or European regulatory pathway.
Why is anakinra used in Still's disease?
Still's disease involves substantial IL-1-driven inflammation in many patients. Anakinra can provide rapid cytokine blockade and is used in adult-onset Still's disease and systemic juvenile idiopathic arthritis.
Does Kineret have interchangeable status in the United States?
Kineret's commercial position should not be treated as interchangeable with a future biosimilar unless the FDA grants that designation to the specific competing product.
What is the largest commercial threat to Kineret?
The largest long-term threat is a clinically substitutable anakinra biosimilar combined with payer pressure. In the near term, the main threat is competition from longer-acting IL-1 inhibitors and alternative immunology therapies.
References
-
Amgen Inc. (2001). Kineret prescribing information. U.S. Food and Drug Administration.
-
European Medicines Agency. (2022). Kineret: EPAR product information and COVID-19 indication. https://www.ema.europa.eu/
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Swedish Orphan Biovitrum AB. (2020). Sobi completes acquisition of the full rights to Kineret and associated products from Amgen. https://www.sobi.com/
-
Swedish Orphan Biovitrum AB. (2024). Annual report 2023. https://www.sobi.com/
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U.S. Food and Drug Administration. (2024). Purple Book: Database of licensed biological products. https://purplebooksearch.fda.gov/
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U.S. Food and Drug Administration. (2024). Kineret prescribing information. https://www.accessdata.fda.gov/-drugsatfda_docs/label/2024/103950s5180lbl.pdf
