Last updated: September 7, 2026
ILUMYA, the brand name for tildrakizumab-asmn, is a commercialized IL-23p19 biologic for moderate-to-severe plaque psoriasis. Sun Pharmaceutical Industries controls the product in the United States and several international markets, while Almirall commercializes tildrakizumab in Europe under the brand name ILUMETRI. The product has a durable biologic-exclusivity position through 2030, but its commercial trajectory is constrained by competition from higher-growth IL-23 and IL-17 therapies, payer pressure, and the absence of an approved psoriatic arthritis indication.
Sun does not separately disclose audited ILUMYA revenue in its public financial statements. The product remains part of the company’s specialty and innovative-medicines portfolio, which has become a major earnings driver. Its value depends on maintaining share in plaque psoriasis, expanding prescriber adoption, defending reimbursement, and potentially securing an additional indication.
What is ILUMYA and how does it work?
ILUMYA is a humanized monoclonal antibody that selectively binds the p19 subunit of interleukin-23. It inhibits IL-23-mediated inflammatory signaling involved in plaque psoriasis.
The FDA approved ILUMYA on March 20, 2018, for adults with moderate-to-severe plaque psoriasis who are candidates for systemic therapy or phototherapy.[1] The approved regimen is:
| Treatment phase |
Dose |
| Initial dose |
100 mg subcutaneously at Week 0 |
| Second dose |
100 mg at Week 4 |
| Maintenance |
100 mg every 12 weeks |
The 12-week maintenance interval is commercially useful because it reduces injection frequency relative with many biologic regimens. ILUMYA is administered by a healthcare professional in the United States, which supports a buy-and-bill reimbursement model but can limit convenience relative to self-injected competitors.
What is the FDA regulatory status of ILUMYA?
ILUMYA has one FDA-approved indication: moderate-to-severe plaque psoriasis in adults. It does not have an FDA-approved indication for psoriatic arthritis, inflammatory bowel disease, or other immune-mediated diseases.
The product was approved through the biologics license application pathway. Because ILUMYA is a biologic, future competition will come through biosimilar applications under the Public Health Service Act rather than through conventional small-molecule ANDA filings.
Key FDA milestones include:
| Milestone |
Date |
| FDA approval |
March 20, 2018 |
| U.S. reference-product biologic exclusivity |
Expected to run through March 2030 |
| Current approved use |
Adult moderate-to-severe plaque psoriasis |
| Dosage form |
100 mg/mL prefilled syringe |
| Administration |
Subcutaneous injection |
The 12-year reference-product exclusivity period is separate from patent protection. A biosimilar could not be licensed before the statutory exclusivity period expired, although biosimilar developers could conduct development activities before that date.[2]
When does ILUMYA lose exclusivity?
ILUMYA’s regulatory exclusivity is expected to expire in March 2030, 12 years after FDA approval. Commercial biosimilar entry could occur after that date, subject to applicable patent rights, litigation, settlement agreements, and FDA review.
The practical loss-of-exclusivity date could therefore differ from the regulatory date. A biosimilar applicant may face:
- Composition-of-matter or antibody-sequence patents
- Manufacturing-process patents
- Formulation and device patents
- Method-of-treatment patents
- Patent litigation under the biosimilar patent-transparency process
- Launch restrictions created by settlement agreements
The most important near-term commercial protection is the biologic exclusivity period. Patent protection may extend beyond 2030, but its commercial effect will depend on the scope and enforceability of issued claims.
What patents protect ILUMYA?
ILUMYA is protected by a portfolio developed around the tildrakizumab antibody, its use in psoriasis, pharmaceutical formulations, and manufacturing. The relevant categories include:
| Patent category |
Commercial purpose |
| Antibody and antigen-binding claims |
Protect tildrakizumab or closely defined antibody sequences |
| Treatment claims |
Cover use in plaque psoriasis and dosing schedules |
| Formulation claims |
Protect stability, concentration, excipients, and storage characteristics |
| Manufacturing claims |
Protect cell culture, purification, and production processes |
| Device or presentation claims |
Protect prefilled syringes or delivery configurations |
The FDA Orange Book is not the primary patent database for ILUMYA because biologics are generally tracked through the Purple Book and the biologics patent-exchange process rather than traditional Orange Book listing practice.[2,3] The absence of a conventional Orange Book patent listing does not mean the product lacks patent protection.
How strong is the ILUMYA patent estate?
ILUMYA has a moderate commercial patent position rather than an unassailable one.
The strongest potential barriers are antibody-specific claims and manufacturing know-how. These rights can be difficult to design around if they cover the molecule’s sequence, binding characteristics, or essential production steps. Method-of-use and formulation patents are usually more vulnerable to validity challenges or non-infringement positions than core antibody claims.
Patent strength is influenced by four factors:
- Whether issued claims cover the exact tildrakizumab sequence.
- Whether claims remain enforceable after patent-term adjustments or terminal disclaimers.
- Whether biosimilar applicants can avoid infringement through alternative formulations or processes.
- Whether Sun and its partners have settled future biosimilar disputes.
No widely reported ILUMYA biosimilar settlement has established an earlier commercial launch date. The absence of a public settlement improves visibility around the 2030 regulatory floor but does not establish that all later-expiring patents will block entry.
How has ILUMYA performed financially?
Sun Pharmaceutical does not report ILUMYA as a separate revenue line. It reports the product within its specialty, innovative-medicines, or related portfolio disclosures. This prevents investors from calculating product-level growth, gross margin, or contribution to operating profit directly from the annual report.
The financial profile has three identifiable characteristics:
| Financial factor |
Effect on ILUMYA |
| Specialty portfolio placement |
Supports higher margins than many generic products |
| Biologic manufacturing and reimbursement |
Creates higher revenue per patient but also higher access friction |
| Multi-product commercial infrastructure |
Reduces standalone selling costs and supports dermatologist coverage |
Sun’s innovative-medicines portfolio includes ILUMYA alongside products such as WINLEVI, CEQUA, ODOMZO, and other specialty assets. Sun has described specialty and innovative medicines as a central growth engine in investor communications and annual filings.[4,5]
The company’s financial disclosures indicate that specialty medicines have become strategically more important, but they do not isolate ILUMYA’s net sales. Product-level estimates published by market-data providers may differ because of channel inventory, gross-to-net deductions, geographic attribution, and partner economics.
What drives ILUMYA revenue?
ILUMYA revenue depends on:
- New patient starts among dermatologists
- Continuation rates after induction
- Insurance approval and step-therapy requirements
- Use of loading-dose and maintenance-dose schedules
- Medicare and commercial payer mix
- Buy-and-bill reimbursement
- Rebates and co-pay support
- Competitive switching from TNF, IL-17, and other IL-23 therapies
The product’s 12-week maintenance schedule can support persistence. Its physician-administered model can also create reimbursement advantages in some channels, although it limits the convenience associated with at-home self-injection.
How does ILUMYA compare with competing psoriasis biologics?
ILUMYA competes in a crowded market dominated by IL-23 and IL-17 agents. The largest commercial competitors include AbbVie’s SKYRIZI, Johnson & Johnson’s TREMFYA, Novartis’ COSENTYX, Eli Lilly’s TALTZ, UCB’s BIMZELX, and Bristol Myers Squibb’s SOTYKTU, an oral TYK2 inhibitor.
| Product |
Company |
Mechanism |
Maintenance profile |
Key commercial advantage |
| ILUMYA |
Sun Pharma |
IL-23p19 antibody |
Every 12 weeks after loading |
Low injection frequency |
| SKYRIZI |
AbbVie |
IL-23p19 antibody |
Approximately every 12 weeks after loading |
Large commercial scale and broad immunology presence |
| TREMFYA |
Johnson & Johnson |
IL-23p19 antibody |
Extended maintenance dosing |
Strong dermatology and immunology infrastructure |
| COSENTYX |
Novartis |
IL-17A antibody |
Monthly or longer intervals depending on regimen |
Broad indications, including psoriatic arthritis |
| TALTZ |
Eli Lilly |
IL-17A antibody |
Monthly maintenance in psoriasis |
Established efficacy and broad label |
| BIMZELX |
UCB |
IL-17A/F antibody |
Periodic maintenance dosing |
High-efficacy positioning |
| SOTYKTU |
Bristol Myers Squibb |
TYK2 inhibitor |
Oral daily therapy |
Convenience without injection |
ILUMYA’s main weakness is indication breadth. SKYRIZI, TREMFYA, COSENTYX, TALTZ, and BIMZELX have broader or expanding immunology opportunities. Competitors with psoriatic arthritis indications can capture patients whose disease extends beyond skin symptoms.
Which companies are challenging ILUMYA?
No major publicly disclosed biosimilar challenger has established a confirmed commercial launch date for tildrakizumab in the United States. Biosimilar competition remains a post-2030 risk rather than an immediate market event.
Potential challengers would likely include large biologics manufacturers and biosimilar specialists with experience in monoclonal antibodies, including Amgen, Sandoz, Celltrion, Samsung Bioepis, Biocon Biologics, Fresenius Kabi, and Viatris. A company could pursue development without publicly identifying a commercial launch plan until patent litigation or regulatory filings become visible.
The absence of a public Paragraph IV challenge is not directly applicable in the same manner as for small-molecule drugs. Biosimilars use a separate patent-notification and litigation framework under the Biologics Price Competition and Innovation Act.[2]
What patent litigation affects ILUMYA?
There is no widely publicized, market-defining U.S. patent litigation campaign involving an ILUMYA biosimilar comparable to major disputes involving Humira, Stelara, or other large biologics.
The principal litigation risk will arise when a biosimilar applicant exchanges patent information with the reference-product sponsor. Disputes could involve:
- Antibody sequence claims
- Genus claims covering anti-IL-23 antibodies
- Treatment claims for plaque psoriasis
- Formulation stability
- Cell-line or purification methods
- Device configuration
Sun may also rely on contractual rights associated with its development and commercialization arrangements. The original tildrakizumab program was developed by Merck and licensed to Sun, while Almirall obtained European commercialization rights.[6,7] Those agreements can affect geographic control, manufacturing rights, royalties, and litigation responsibilities.
What licensing deals support ILUMYA commercialization?
Sun licensed tildrakizumab from Merck in 2014. The agreement gave Sun development and commercialization rights in specified markets, including the United States. Almirall later entered into an agreement with Sun for European commercialization, where the product is marketed as ILUMETRI.[6,7]
The structure has two commercial implications:
- Sun does not control all global ILUMYA-related economics.
- Regional sales, royalties, manufacturing costs, and milestone obligations may be allocated differently between Sun, Merck, and Almirall.
The U.S. market remains the central strategic asset because it is the largest commercial psoriasis market and the primary region where Sun markets the ILUMYA brand directly.
What generic entry risks exist for ILUMYA?
Conventional generic entry is not the primary risk. The relevant threat is biosimilar substitution and formulary competition after regulatory exclusivity.
Near-term risk through 2029
Near-term erosion risk is limited by the absence of an approved biosimilar pathway before the end of reference-product exclusivity. Commercial pressure will instead come from rebate competition, formulary exclusion, and switching to rival biologics.
2030 to 2032 risk
This is the most likely initial biosimilar-risk window. The timing will depend on:
- FDA biosimilar approval
- Patent litigation outcomes
- Settlement terms
- Interchangeability status
- Payer adoption
- Manufacturing capacity
- Provider willingness to switch stable patients
Longer-term risk
If multiple biosimilars enter, ILUMYA could experience price compression, lower net sales per patient, and reduced formulary leverage. The product’s relatively smaller commercial scale compared with SKYRIZI and TREMFYA could reduce biosimilar developers’ incentive to enter quickly, but it could also make the brand more vulnerable to payer-directed switching.
What is the geographic coverage of ILUMYA?
| Region |
Brand |
Commercial party |
| United States |
ILUMYA |
Sun Pharma |
| Europe |
ILUMETRI |
Almirall |
| Selected international markets |
ILUMYA or local designation |
Rights vary by territory |
Geographic economics are therefore divided. Sun captures direct U.S. product economics, while European sales are linked to Almirall’s commercialization and contractual arrangements. The U.S. market has greater revenue potential but also stronger payer and competitor intensity.
What is the outlook for ILUMYA revenue?
ILUMYA should remain a meaningful specialty asset through the late 2020s, but it is unlikely to become Sun’s sole or dominant growth driver. Its revenue trajectory will depend more on share retention than on rapid category expansion.
The base-case commercial outlook is:
| Period |
Expected market dynamic |
| 2025-2027 |
Continued growth or stabilization through psoriasis demand, with intense rebate competition |
| 2028-2029 |
Increasing pressure from rival IL-23 agents and possible pre-entry biosimilar preparation |
| 2030 |
End of FDA reference-product exclusivity |
| 2030-2032 |
Potential biosimilar entry, litigation, and payer-driven price erosion |
| After 2032 |
Greater erosion risk unless patent litigation, new indications, or lifecycle management delays substitution |
The strongest upside scenario would involve a psoriatic arthritis approval, superior persistence data, stronger real-world outcomes, or a differentiated administration and reimbursement strategy. The principal downside scenario is accelerated share loss to SKYRIZI and TREMFYA before biosimilar entry, followed by price erosion after 2030.
Key Takeaways
- ILUMYA is tildrakizumab-asmn, an IL-23p19 biologic approved in the United States in March 2018.
- FDA reference-product biologic exclusivity is expected to run through March 2030.
- Sun Pharma does not separately disclose ILUMYA revenue, so product-level financial estimates are not directly verifiable from audited company filings.
- The product has a moderate patent position built around antibody, formulation, manufacturing, and method-of-use rights.
- The main commercial competitors are SKYRIZI, TREMFYA, COSENTYX, TALTZ, BIMZELX, and SOTYKTU.
- ILUMYA has a favorable 12-week maintenance schedule but lacks the broader indication profile of several competing biologics.
- No major publicly disclosed U.S. biosimilar launch date has been established.
- The principal erosion window begins after March 2030 and could intensify between 2030 and 2032.
- The largest value drivers are U.S. persistence, payer access, specialty-portfolio profitability, and any future label expansion.
FAQs
Is ILUMYA a biosimilar or a reference biologic?
ILUMYA is the reference biologic for tildrakizumab-asmn in the United States. It is not a biosimilar.
Does ILUMYA treat psoriatic arthritis?
No. ILUMYA is FDA-approved for moderate-to-severe plaque psoriasis. It does not have an FDA-approved psoriatic arthritis indication.
Is ILUMYA administered at home?
In the United States, ILUMYA is administered subcutaneously by a healthcare professional. This differs from competitors that are commonly dispensed for self-administration.
Does ILUMYA have an Orange Book patent listing?
Biologic patent protection is generally handled through the Purple Book and the BPCIA patent-exchange framework rather than conventional Orange Book listing practice. The lack of a traditional Orange Book listing does not eliminate patent protection.
What is the biggest investment risk for ILUMYA?
The largest risk is commercial share loss before 2030 to SKYRIZI, TREMFYA, and other IL-23 or IL-17 therapies, followed by biosimilar and payer-driven price erosion after reference-product exclusivity ends.
References
- U.S. Food and Drug Administration. (2018). FDA approves new treatment for moderate-to-severe plaque psoriasis.
- U.S. Food and Drug Administration. (2024). Purple Book: Database of licensed biological products.
- U.S. Food and Drug Administration. (2024). Approved drug products with therapeutic equivalence evaluations.
- Sun Pharmaceutical Industries Ltd. (2024). Annual report 2023-24.
- Sun Pharmaceutical Industries Ltd. (2025). Annual report 2024-25.
- Sun Pharmaceutical Industries Ltd. (2014). Sun Pharma licenses tildrakizumab from Merck for psoriasis.
- Almirall, S.A. (2017). Almirall and Sun Pharma enter into agreement for tildrakizumab in Europe.
