Last updated: September 8, 2026
SILIQ is a U.S.-marketed biologic for moderate-to-severe plaque psoriasis. Its commercial position is constrained by a crowded IL-17 and IL-23 market, a boxed warning for suicidal ideation and behavior, mandatory REMS enrollment, and limited product-level financial disclosure by Bausch Health. The product retains clinical value in patients requiring rapid, high-level skin clearance, but its growth ceiling is lower than those of newer IL-23 therapies with less restrictive safety positioning.
What is SILIQ and who markets brodalumab?
SILIQ is the U.S. brand name for brodalumab, a fully human monoclonal antibody targeting interleukin-17 receptor A, or IL-17RA. The drug blocks signaling from several IL-17 cytokines rather than binding selectively to IL-17A.
Bausch Health markets SILIQ in the United States through its Ortho Dermatologics business. The product originated from a collaboration involving Amgen and AstraZeneca. Amgen discontinued development participation in 2015 after safety concerns related to suicidal ideation, while AstraZeneca transferred U.S. commercial rights to Valeant Pharmaceuticals, now Bausch Health.[1]
| Attribute |
SILIQ |
| Active ingredient |
Brodalumab |
| Mechanism |
Human monoclonal antibody against IL-17 receptor A |
| U.S. indication |
Moderate-to-severe plaque psoriasis in adults who are candidates for systemic therapy or phototherapy |
| FDA approval |
February 2017 |
| Standard dose |
210 mg subcutaneously at weeks 0, 1 and 2, then every two weeks |
| U.S. marketer |
Bausch Health / Ortho Dermatologics |
| Administration |
Self-injection after appropriate training |
| Key restriction |
SILIQ REMS |
| Primary competitors |
Cosentyx, Taltz, Bimzelx, Tremfya, Skyrizi, Ilumya and Sotyktu |
The FDA label requires discontinuation if adequate response is not achieved by weeks 12 to 16. SILIQ is not approved for pediatric psoriasis, psoriatic arthritis or inflammatory bowel disease.[2]
What is the FDA and regulatory status of SILIQ?
SILIQ remains FDA-approved for adult plaque psoriasis. Its major regulatory differentiator is a boxed warning for suicidal ideation and behavior.
The SILIQ REMS requires prescriber certification, pharmacy certification and patient enrollment. Pharmacies may dispense the drug only after verifying the required conditions. The REMS creates operational friction that competing biologics generally do not have.
Key FDA milestones
| Date |
Regulatory event |
| February 2017 |
FDA approves brodalumab for moderate-to-severe plaque psoriasis |
| 2017 |
Boxed warning and SILIQ REMS implemented because of suicidal ideation and behavior concerns |
| Ongoing |
FDA labeling limits treatment to adults with plaque psoriasis who are candidates for systemic therapy or phototherapy |
The safety profile affects more than prescribing behavior. It also influences payer formulary placement, specialty-pharmacy workflows, patient onboarding costs and physician willingness to use brodalumab before other biologic options.
The warning does not establish that brodalumab causes suicide. It reflects observed events in the clinical-development program and the absence of a definitive method to exclude a causal relationship. The FDA requires prescribers to evaluate patients for suicidal ideation and behavior before treatment and during therapy.[2]
How does SILIQ compare with competing psoriasis biologics?
SILIQ has strong efficacy characteristics but weaker commercial positioning than many newer competitors.
Efficacy and positioning
Brodalumab produced high rates of PASI 75, PASI 90 and complete or near-complete skin clearance in pivotal trials. Its IL-17RA mechanism can produce rapid clinical response, which remains relevant for patients who need fast improvement.
The market has shifted toward IL-23 inhibitors such as risankizumab and guselkumab. These therapies are administered less frequently after induction and do not carry the same boxed warning or REMS structure. Bimekizumab, an IL-17A and IL-17F inhibitor, also competes for high-efficacy patients.
| Product |
Target |
Maintenance dosing pattern |
Commercial implication |
| SILIQ |
IL-17RA |
Every two weeks |
High efficacy but REMS and boxed-warning burden |
| Cosentyx |
IL-17A |
Usually every four weeks after loading |
Established IL-17 franchise |
| Taltz |
IL-17A |
Every four weeks for many patients |
Strong dermatology presence |
| Bimzelx |
IL-17A and IL-17F |
Less frequent maintenance than SILIQ in many regimens |
High-efficacy entrant |
| Tremfya |
IL-23 p19 |
Approximately every eight weeks after induction |
Lower treatment frequency |
| Skyrizi |
IL-23 p19 |
Approximately every 12 weeks after induction |
Strong convenience and market growth |
| Ilumya |
IL-23 p19 |
Every 12 weeks after induction |
Office-administered option |
| Sotyktu |
TYK2 inhibitor |
Daily oral dosing |
Oral alternative without biologic injection |
SILIQ’s principal commercial weakness is not lack of efficacy. It is the combination of comparable efficacy, more frequent injections, a REMS requirement and a safety perception that can steer patients toward IL-23 therapies.
What is the market size and competitive outlook for SILIQ?
The U.S. psoriasis market is a large specialty-pharmaceutical market dominated by biologics. Growth has concentrated in products with durable efficacy, convenient administration, broad payer access and expanding indications.
SILIQ operates in a mature segment where new prescriptions are influenced by:
- Formulary rebates and preferred-product status
- Step-therapy requirements
- Prior authorization
- Physician familiarity
- Injection frequency
- Safety monitoring
- Patient support services
- Use after failure of TNF, IL-17 or IL-23 therapy
Brodalumab is more likely to be used as a later-line or switch option than as the default first biologic. Physicians may select it for patients who need rapid clearance or who have failed other mechanisms. The safety warning reduces its use in patients with a history of depression, suicidal behavior or substantial psychiatric risk.
The product also lacks major label expansion drivers. SILIQ is not approved for psoriatic arthritis, unlike several competing biologics. It is not approved for Crohn’s disease or ulcerative colitis, and IL-17 pathway therapies carry inflammatory bowel disease considerations that can narrow prescribing in patients with gastrointestinal comorbidity.
What is the financial trajectory of SILIQ?
Bausch Health does not generally disclose audited, standalone SILIQ revenue in its public annual reports. It reports performance at broader business-unit levels, including Ortho Dermatologics and other pharmaceutical categories. As a result, product-level revenue, gross margin and operating profit cannot be calculated from Bausch’s public filings alone.[3]
The commercial trajectory is best characterized as a mature, niche dermatology asset rather than a major growth product.
Revenue drivers
SILIQ revenue depends on:
- New patient starts in moderate-to-severe plaque psoriasis.
- Reimbursement access and specialty-pharmacy approval.
- Persistence after the early treatment-response period.
- Use in patients who have failed other biologics.
- Bausch’s ability to maintain price and limit net discounting.
Revenue constraints
The main constraints are:
- Competition from IL-23 biologics with less frequent dosing.
- A boxed warning and REMS.
- No psoriasis-related expansion into psoriatic arthritis.
- Bausch’s smaller dermatology commercial platform compared with AbbVie, Johnson & Johnson, Novartis and Lilly.
- Payer pressure in a crowded biologic category.
- Potential erosion after key patent protection expires.
The product’s economic value is likely higher to Bausch as part of a dermatology portfolio than as a standalone growth engine. Cross-selling, specialty-pharmacy relationships and shared field infrastructure can lower commercial costs, but the company’s public reporting does not isolate SILIQ’s contribution.
What patents protect SILIQ and when does brodalumab lose exclusivity?
The principal U.S. patent associated with SILIQ is U.S. Patent No. 8,545,850, covering anti-IL-17 receptor A antibodies. Public patent databases report an expiration date in December 2025, subject to any applicable patent-term adjustment, patent-term extension or regulatory exclusivity.[4]
| Patent |
Subject matter |
Reported U.S. expiration |
| U.S. 8,545,850 |
Anti-IL-17 receptor A antibodies |
December 2025 |
The patent position should be separated from FDA regulatory exclusivity. SILIQ received orphan-drug designation? No. Its plaque-psoriasis approval did not create orphan exclusivity. The main U.S. commercial barrier is therefore patent protection, regulatory approval requirements and the practical cost of developing and commercializing a competing injectable biologic.
A follow-on product would generally be a biosimilar or interchangeable biosimilar rather than a conventional small-molecule generic. A biosimilar applicant must demonstrate high similarity to the reference product and satisfy FDA requirements under the Biologics Price Competition and Innovation Act.
What biosimilar and generic entry risks exist for SILIQ?
SILIQ faces biologic competition rather than traditional generic substitution.
Biosimilar risk
Biosimilar entry depends on:
- Availability of a viable reference-product pathway.
- Remaining patent protection.
- Manufacturing comparability.
- Clinical and analytical development cost.
- Market size sufficient to justify entry.
- Payer willingness to use a biosimilar.
- Interchangeability strategy.
- Litigation and settlement outcomes.
Brodalumab’s relatively limited commercial scale may reduce the incentive for multiple biosimilar manufacturers to invest in a competing product. At the same time, the product’s established mechanism and subcutaneous administration could make it technically accessible to experienced biologics manufacturers.
Paragraph IV challenges
A Paragraph IV certification applies to an ANDA for a small-molecule drug, not to the principal biosimilar pathway for a monoclonal antibody. Therefore, the relevant challenge framework for a SILIQ follow-on is generally BPCIA patent litigation rather than a standard Hatch-Waxman Paragraph IV case.
No major publicly disclosed Paragraph IV litigation is central to SILIQ’s current market profile. The more relevant risk is a future biosimilar patent challenge after the principal U.S. patent barrier expires.
What is the Orange Book status of SILIQ?
SILIQ is listed in the FDA Orange Book because its original approval was filed as a drug product under an NDA before the transition of many biologics to the Public Health Service Act framework. The Orange Book identifies patents submitted by the NDA holder and associated exclusivity information.[5]
The Orange Book does not guarantee that a listed patent will block every competing product. It also does not determine the outcome of patent litigation. A competitor must assess claim scope, validity, enforceability and the relevance of each listed patent to its proposed product.
For commercial planning, the December 2025 expiration associated with U.S. Patent No. 8,545,850 is the principal publicly reported timing marker. Actual entry timing can differ because of litigation, settlement, regulatory review, manufacturing readiness and patent-term calculations.
What patent litigation and settlement agreements affect SILIQ?
SILIQ has not generated the level of public patent litigation associated with blockbuster biologics such as Humira, Stelara or Enbrel. The absence of a widely reported settlement does not eliminate future biosimilar litigation risk.
A future dispute could involve:
- Antibody sequence or binding claims
- IL-17RA target claims
- Formulation claims
- Dosing or administration claims
- Manufacturing-cell-line or process claims
- Patent-term calculations
- Interchangeability or substitution issues
The commercial importance of formulation and manufacturing patents may increase after the core composition-of-matter protection expires. Injectable biologics can remain difficult to copy even after primary patents lapse because analytical similarity, process control and device compatibility require significant investment.
What formulations and manufacturing processes are protected?
SILIQ is supplied as a single-dose prefilled syringe containing 210 mg of brodalumab in 1.5 mL. The commercial formulation uses a subcutaneous delivery system and requires cold-chain handling.
Relevant intellectual-property categories include:
- Brodalumab antibody sequence and structural claims
- Binding to IL-17 receptor A
- Cell-culture and purification processes
- Protein concentration and stability
- Subcutaneous formulation
- Prefilled-syringe presentation
- Device and container-closure components
- Dosing regimens
Public sources do not support treating every formulation or process patent as a guaranteed market-exclusion right. A biosimilar manufacturer may design around specific claims, challenge validity or rely on alternative manufacturing processes.
How strong is the SILIQ patent estate?
SILIQ’s patent estate is commercially moderate rather than exceptionally strong.
Strengths
- A core antibody patent has provided protection through the mid-2020s.
- Manufacturing a comparable monoclonal antibody requires substantial technical capability.
- The product has an established FDA safety and efficacy record.
- A biosimilar entrant must overcome both patent and development barriers.
Weaknesses
- The core reported U.S. patent expires relatively soon compared with newer biologics.
- The product has limited publicly visible lifecycle management.
- No broad label expansion has materially extended its commercial opportunity.
- REMS requirements can reduce market demand and patient persistence.
- The product competes against multiple high-efficacy therapies with more convenient dosing.
What generic launch scenarios exist for SILIQ?
Three scenarios are commercially plausible:
| Scenario |
Timing |
Market effect |
| No near-term biosimilar |
After core patent expiry |
Bausch retains most demand, with continued payer pressure |
| Single biosimilar entrant |
After patent and regulatory resolution |
Moderate price erosion and selective formulary substitution |
| Multiple biosimilar entrants |
Several years after patent expiry |
Greater rebate pressure, lower net price and declining branded share |
The most likely erosion pattern for a biologic such as SILIQ is gradual rather than an immediate pharmacy-level substitution event. Payers may prefer a biosimilar for new starts while retaining SILIQ for established patients. Interchangeability status, contracting and specialty-pharmacy distribution will determine the speed of conversion.
What is SILIQ’s geographic coverage and licensing structure?
Brodalumab has been commercialized under different brands and rights arrangements outside the United States. In Europe, the product was marketed as Kyntheum by LEO Pharma. Kyowa Kirin has held rights in Japan under the Lumicef brand.
The geographic structure limits Bausch’s global upside. Bausch’s principal economic exposure is the U.S. market, while international commercialization has relied on partners and regional license arrangements. International sales therefore do not necessarily flow through Bausch’s reported revenue in the same manner as U.S. sales.
Key Takeaways
- SILIQ is a high-efficacy IL-17RA biologic for adult plaque psoriasis.
- Bausch Health markets the product in the United States through Ortho Dermatologics.
- FDA approval remains active, but the boxed warning and SILIQ REMS materially restrict adoption.
- IL-23 competitors have stronger convenience and safety-positioning advantages.
- Bausch does not publicly disclose standalone SILIQ revenue, preventing a reliable product-level financial model from public filings alone.
- U.S. Patent No. 8,545,850 is publicly reported to expire in December 2025.
- Follow-on competition is more likely to involve biosimilar litigation than a traditional Paragraph IV generic challenge.
- SILIQ is best viewed as a mature specialty asset with durable niche demand and meaningful post-patent erosion risk.
FAQs About SILIQ Market and Patent Risk
Is SILIQ being discontinued?
No public FDA action establishes discontinuation of SILIQ in the United States. The product remains an approved Bausch Health dermatology product.
Is SILIQ a biologic or a generic drug?
SILIQ is a biologic monoclonal antibody. A future competitor would generally pursue a biosimilar pathway rather than a conventional generic ANDA.
Why does SILIQ have a boxed warning?
The FDA required a boxed warning because suicidal ideation and behavior, including completed suicides, occurred during the brodalumab development program. The warning is implemented through the SILIQ REMS.
Can SILIQ treat psoriatic arthritis?
No. SILIQ’s U.S. label is for moderate-to-severe plaque psoriasis in adults. It is not approved for psoriatic arthritis.
What is the main investment risk for SILIQ?
The principal risks are competitive displacement by IL-23 biologics, limited product-level growth disclosure, REMS-related prescribing friction and biosimilar or other follow-on competition after core patent protection expires.
References
- AstraZeneca. (2015). AstraZeneca and Valeant Pharmaceuticals enter agreement for brodalumab in psoriasis.
- U.S. Food and Drug Administration. (2023). SILIQ (brodalumab) prescribing information.
- Bausch Health Companies Inc. (2024). Annual report for the fiscal year ended December 31, 2023.
- United States Patent and Trademark Office. (2008). U.S. Patent No. 8,545,850: Anti-IL-17 receptor A antibodies.
- U.S. Food and Drug Administration. (2024). Approved drug products with therapeutic equivalence evaluations: Orange Book.
