izokibep (ABY-035) / Affibody - LARVOL DELTA

Efficacy of Izokibep, a Novel IL-17A Inhibitor, in Patients With Active Psoriatic Arthritis: Composite Measures of Disease Activity and Patient-Reported Outcomes From a Randomized, Double-Blind, Placebo-Controlled, Multicenter, Phase 2b/3 Study (ACR Convergence 2026) - No abstract available

Clinical • P2/3 data • P2b data • Patient reported outcomes • Immunology • Inflammatory Arthritis • Psoriatic Arthritis • Rheumatology • Seronegative Spondyloarthropathies • IL17A

Efficacy of Izokibep, a Novel IL-17A Inhibitor, in Patients With Active Psoriatic Arthritis: A Subgroup Analysis From a Randomized, Double-Blind, Placebo-Controlled, Multicenter, Phase 2b/3 Study (ACR Convergence 2026) - No abstract available

Clinical • P2/3 data • P2b data • Immunology • Inflammatory Arthritis • Psoriatic Arthritis • Rheumatology • Seronegative Spondyloarthropathies • IL17A

HiSCR100 as the New Benchmark. A Critical Meta-Analysis of the Gap Between Statistical Significance and Complete Disease Resolution in Contemporary Hidradenitis Suppurativa Trials (Povorcitinib, Izokibep, Bimekizumab) (EADV 2026) - No abstract available

Retrospective data • Dermatology • Hidradenitis Suppurativa • Immunology

IHS4 outcomes to week 32 with izokibep, a novel interleukin-17A inhibitor, in patients with moderate to severe hidradenitis suppurativa: Results from a randomised, double-blind, placebo-controlled, multicentre, phase 3 study (EADV 2026) - No abstract available

Clinical • P3 data • Dermatology • Hidradenitis Suppurativa • Immunology • IL17A

Efficacy of izokibep, a novel interleukin-17A inhibitor, in moderate to severe hidradenitis suppurativa: A patient subgroup analysis from a randomised, double-blind, placebo-controlled, multicentre, phase 3 study (EADV 2026) - No abstract available

Clinical • P3 data • Dermatology • Hidradenitis Suppurativa • Immunology • IL17A

IL-17 ligand-targeting inhibitors in psoriatic arthritis: a focused systematic review and network meta-analysis of efficacy, safety, and certainty of evidence. (PubMed, Front Immunol) - "Ixekizumab Q2W had the highest ACR50 P-score, followed by bimekizumab 160 mg with loading and ixekizumab Q4W; however, active-treatment confidence intervals overlapped...Sonelokimab and izokibep showed favorable exploratory estimates but very low certainty...The protocol was registered in PROSPERO (CRD420251156756). https://www.crd.york.ac.uk/PROSPERO/view/CRD420251156756, identifier CRD420251156756."

Clinical • Journal • Retrospective data • Review • Immunology • Infectious Disease • Inflammatory Arthritis • Psoriasis • Psoriatic Arthritis • Rheumatology • Seronegative Spondyloarthropathies • IL17A

Systemic Treatment of Psoriasis: Current Evidence on Efficacy and Safety. (PubMed, J Dermatol) - "Older conventional systemic agents, such as cyclosporin, acitretin, or methotrexate, remain useful in selected settings, especially when treatment options are limited by cost or availability, when short-term disease control is needed, or when the patient prefers these treatments...Biologics targeting TNF-α or anti-IL-12/23p40 ustekinumab have established the biologic treatment era, and remain clinically relevant, especially for patients having psoriatic arthritis or prioritizing long-term safety...Targeted oral therapies increase options for patients who prefer non-injectable treatment; established or emerging agents include apremilast, deucravacitinib, icotrokinra, zasocitinib, envudeucitinib, and orismilast. Emerging IL-17-directed agents, including sonelokimab and izokibep, may further refine pathway targeting. Selection of treatment should be decided dependently on the completeness of skin clearance achieved, speed and duration of responses, effectiveness on..."

Journal • Review • Candidiasis • Dermatology • Gastroenterology • Gastrointestinal Disorder • Immunology • Inflammatory Arthritis • Inflammatory Bowel Disease • Oncology • Psoriasis • Psoriatic Arthritis • Rheumatology • Seronegative Spondyloarthropathies • IL12A • IL17A • TNFA

Investigational IL-17A antagonist in the treatment of psoriatic arthritis - a review. (PubMed, Expert Opin Investig Drugs) - "This generation includes small, injectable molecules such as sonelokimab and izokibep; oral molecules; and bispecific monoclonal antibodies...The future of PsA treatments is contingent upon the implementation of precision medicine. The overarching objective is no longer to treat to target, but rather to treat to intercept, while ensuring the highest rate of control and tolerance for the patient."

Journal • Review • Immunology • Inflammatory Arthritis • Psoriatic Arthritis • Rheumatology • Seronegative Spondyloarthropathies

Investigational interleukin 17A antagonists in the treatment of psoriatic arthritis. (PubMed, Expert Opin Investig Drugs) - "This generation includes small, injectable molecules such as sonelokimab and izokibep; oral molecules; and bispecific monoclonal antibodies...This could help control disease early and prevent progression, beyond the current Treat-to-Target strategy which mainly focuses on managing existing symptoms. The overarching objective is no longer to treat to target, but rather to treat to intercept, while ensuring the highest rate of control and tolerance for the patient."

Journal • Review • Immunology • Inflammatory Arthritis • Psoriatic Arthritis • Rheumatology • Seronegative Spondyloarthropathies

Efficacy and Safety of Izokibep, a Novel IL-17A Inhibitor, in Patients With Active Psoriatic Arthritis: Week 52 Results From a Randomised, Double-Blind, Placebo-Controlled, Multicentre, Phase 2b/3 Study (EULAR 2026) - P2/3 | "Substantial percentages of patients originally randomised to izokibep or switching from placebo to izokibep achieved ACR50/70, PASI 90/100, and MDA by the end of the study. Izokibep treatment was well tolerated, with no new observed safety signals."

Clinical • P2/3 data • P2b data • Candidiasis • Gastroenterology • Gastrointestinal Disorder • Immunology • Infectious Disease • Inflammatory Arthritis • Inflammatory Bowel Disease • Musculoskeletal Diseases • Pruritus • Psoriasis • Psoriatic Arthritis • Rheumatology • Seronegative Spondyloarthropathies • Suicidal Ideation • Ulcerative Colitis • IL17A

Positive 52-week Phase 2b/3 Data of Izokibep in Psoriatic Arthritis to be Presented at EULAR 2026 (TradingView) - "Week 52 results demonstrated continued improvement over time for patients randomized to either of the izokibep groups (160 mg every two weeks (Q2W) or 160 mg every week (QW)), and rapid improvement in patients following crossover from placebo to izokibep treatment...Professor Philip Mease, investigator in the study, will present the week 52 study results in an oral presentation at EULAR 2026 on Wednesday, June 3."

P2/3 data • Psoriatic Arthritis

Efficacy of izokibep, a novel interleukin-17A inhibitor, in moderate to severe hidradenitis suppurativa: Week 32 results from a randomized, double-blind, placebo-controlled, multicenter, phase 3 study (AAD 2026) - P3 | "No new safety signals were observed with extended exposure to izokibep or upon crossover. At week 32, patients continuously receiving izokibep demonstrated sustained efficacy, and patients initially receiving placebo achieved notable rates of response following crossover to izokibep."

Clinical • P3 data • Dermatology • Hidradenitis Suppurativa • Immunology • IL17A

The Pathophysiological Significance of Dual Inhibition of IL-17A and IL-17F in Psoriatic Arthritis and Axial Spondyloarthritis. (PubMed, Mediterr J Rheumatol) - "Conducting a search through PubMed/MEDLINE, Scopus, and Web of Science, using keywords and Medical Subject Headings (MeSH) terms such as "spondyloarthritis", "psoriatic arthritis", "IL-17A", "IL-17F", "IL-23", "IL-23 independent mechanisms", "dual inhibition", "pathogenesis", "gut-joint axis", "secukinumab", "ixekizumab", "bimekizumab", "sonelokimab", we select the relevant literature for this comprehensive pathophysiological narrative...Inhibiting both IL-17A and IL-17F signifies not only a significant therapeutic advancement but also a vital strategy towards overcoming the limitations of our current armamentarium in achieving deeper and more sustained remission in SpA. Future studies and long-term data will be essential in determining the position of dual IL-17A/F inhibitors within treatment guidelines."

Journal • Review • Ankylosing Spondylitis • Immunology • Inflammation • Inflammatory Arthritis • Psoriasis • Psoriatic Arthritis • Rheumatology • Seronegative Spondyloarthropathies • Spondylarthritis • IL17A • IL23A

Positive 52-week Phase 2b/3 Data of Izokibep in Psoriatic Arthritis to be Presented at ACR Convergence 2025 (Affibody Press Release) - "Continued improvement after week 16 was seen for patients randomized to either of the izokibep groups (160 mg once every two weeks (Q2W) or 160 mg QW), and rapid improvement was observed in patients following crossover from placebo to izokibep treatment. By week 52, approximately half of all patients achieved ACR50 (izokibep Q2W: 50%, izokibep QW: 57%, placebo-izokibep QW: 51%)...Substantial percentages of patients in all groups also achieved the high-hurdle endpoints of ACR70 (izokibep Q2W: 36%, izokibep QW: 42%, placebo-izokibep QW: 42%), PASI90 (izokibep Q2W: 63%, izokibep QW: 69%, placebo-izokibep QW: 65%), PASI100 (izokibep Q2W: 55%, izokibep QW: 64%, placebo-izokibep QW: 58%), and MDA (izokibep Q2W: 47%, izokibep QW: 52%, placebo-izokibep QW: 47%) at week 52."

P2/3 data • Psoriatic Arthritis

Efficacy and Safety of Izokibep, a Novel IL-17A Inhibitor, in Patients with Active Psoriatic Arthritis: Week 52 Results from a Randomized, Double-Blind, Placebo-Controlled, Multicenter, Phase 2b/3 Study (ACR Convergence 2025) - P2/3 | "IZO demonstrated durable efficacy across several measures of PsA disease activity over 52 wks. Substantial percentages of pts originally randomized to IZO or switching from PBO to IZO achieved ACR50/70, PASI 90/100, and MDA by the end of the study. IZO treatment was well tolerated, with a safety profile generally consistent with that of legacy IL-17A inhibitors."

Clinical • Late-breaking abstract • P2/3 data • P2b data • Candidiasis • Dermatology • Gastroenterology • Gastrointestinal Disorder • Immunology • Infectious Disease • Inflammatory Arthritis • Inflammatory Bowel Disease • Musculoskeletal Diseases • Pruritus • Psoriatic Arthritis • Psychiatry • Rheumatology • Seronegative Spondyloarthropathies • Suicidal Ideation • Ulcerative Colitis • IL17A

Efficacy and safety of izokibep, a novel interleukin-17A inhibitor, in moderate to severe hidradenitis suppurativa: Week 16 results from a randomised, double-blind, placebo-controlled, multicentre, phase 3 study (EADV 2025) - P3 | "Conclusion Early improvements previously reported with izokibep over placebo were sustained across key HS disease measures at week 16, with over one-third of patients achieving HiSCR75. No new safety signals were observed with izokibep."

Clinical • Late-breaking abstract • P3 data • Candidiasis • Dermatology • Fatigue • Gastroenterology • Gastrointestinal Disorder • Hidradenitis Suppurativa • Immunology • Infectious Disease • Inflammation • Inflammatory Bowel Disease • Psychiatry • Respiratory Diseases • Suicidal Ideation • IL17A

Positive 16-week Phase 3 Data of Izokibep in Hidradenitis Suppurativa Presented at EADV 2025 (Affibody Press Release) - "Data from week 16 demonstrate deepening of responses over time with statistically significant improvement across multiple efficacy endpoints. 37% of patients treated with 160 mg izokibep weekly (QW) achieved HiSCR75 compared to 20% of patients receiving placebo (p<0.01)...In higher order endpoints, 24% of patients treated with izokibep achieved HiSCR90, compared to 12% with placebo (p<0.05), and 21% of patients treated with izokibep achieved HiSCR100, compared to 9% with placebo (p<0.01)....Izokibep was generally well-tolerated with a favorable safety profile consistent with previous studies. There were no reports of Candida infection, inflammatory bowel disease, or suicidal ideation with izokibep."

Late-breaking abstract • P3 data • Hidradenitis Suppurativa

Efficacy and safety of izokibep in patients with active psoriatic arthritis: a randomised, double-blind, placebo-controlled, phase 2 study. (PubMed, Ann Rheum Dis) - "Izokibep resulted in significant and clinically meaningful improvements over placebo across multiple disease domains, and the originally randomised 80-mg dose showed continued improvements to week 46. There were no unexpected safety risks identified. Izokibep's small size and high potency have the potential for further improved disease control, justifying additional investigation of higher doses."

Journal • P2 data • Dermatology • Immunology • Inflammatory Arthritis • Psoriasis • Psoriatic Arthritis • Rheumatology • Seronegative Spondyloarthropathies • IL17A

Hidradenitis Suppurativa Study of Izokibep (clinicaltrials.gov) - P3 | N=258 | Terminated | Sponsor: ACELYRIN Inc. | Completed ➔ Terminated; Per our 13Aug24 press release, we announced discontinuation of internal development in this indication. This decision was not due to safety reasons.

Trial termination • Dermatology • Hidradenitis Suppurativa • Immunology

Hidradenitis Suppurativa Study of Izokibep (clinicaltrials.gov) - P3 | N=258 | Completed | Sponsor: ACELYRIN Inc. | Active, not recruiting ➔ Completed

Trial completion • Dermatology • Hidradenitis Suppurativa • Immunology

Next-Generation Anti-IL-17 Agents for Psoriatic Disease: A Pipeline Review. (PubMed, Am J Clin Dermatol) - "Key agents under investigation include netakimab, vunakizumab, xeligekimab, gumokimab, HB0017, CJM 112, JS005, 608, LZM012, ZL-1102, izokibep, sonelokimab, DC-806, DC-853, and LEO 153339. Both preclinical and clinical trial data for each agent are summarized, with an emphasis on their efficacy, adverse effects, immunogenicity, and future outlooks."

Journal • Dermatology • Immunology • Inflammatory Arthritis • Psoriasis • Psoriatic Arthritis • Rheumatology • Seronegative Spondyloarthropathies

Phase 2b Pivotal Study of Izokibep in Non-infectious, Intermediate-, Posterior- or Pan-uveitis (clinicaltrials.gov) - P2 | N=96 | Terminated | Sponsor: ACELYRIN Inc. | Active, not recruiting ➔ Terminated; Study primary and secondary endpoints did not achieve statistical significance.

Trial termination • Ocular Inflammation • Ophthalmology • Uveitis

Affibody regains worldwide rights to izokibep (Affibody Press Release) - "Affibody today announced that the company will regain all rights to izokibep...In 2021, Affibody and ACELYRIN, INC. entered into a license and collaboration agreement granting ACELYRIN worldwide development and commercialization rights to izokibep, except in selected Asian countries. Following ACELYRIN’s previous announcement to halt internal development of izokibep the agreement will now be terminated. The termination will be effective after a three-month notice period after which all rights will revert, and the asset will be transferred to Affibody."

Commercial • Hidradenitis Suppurativa • Psoriatic Arthritis

Interleukin-17: A pleiotropic cytokine implicated in inflammatory, infectious, and malignant disorders. (PubMed, Cytokine Growth Factor Rev) - "Four FDA-approved drugs-secukinumab (for ankylosing spondylitis, enthesitis-related arthritis, hidradenitis suppurativa, non-radiographic axial spondyloarthritis, plaque psoriasis, and psoriatic arthritis), ixekizumab (for ankylosing spondylitis, non-radiographic axial spondyloarthritis, plaque psoriasis, and psoriatic arthritis), brodalumab (for plaque psoriasis), and bimekizumab (for plaque psoriasis)-suppress the IL-17 pathway, with more in development, including netakimab, sonelokimab, izokibep, and CJM112. These agents and others are being studied across a spectrum of disorders. Understanding the complicated interplay between IL-17 and other immune mediators may yield new treatments for inflammatory/autoimmune conditions and malignancies."

Journal • Ankylosing Spondylitis • Dermatology • Genetic Disorders • Hidradenitis Suppurativa • Idiopathic Arthritis • Immunology • Infectious Disease • Inflammatory Arthritis • Oncology • Psoriasis • Psoriatic Arthritis • Rheumatoid Arthritis • Rheumatology • Seronegative Spondyloarthropathies • Skin Cancer • Solid Tumor • Spondylarthritis • IL17A • IL17C • IL17RA • IL23A

Phase 2b Pivotal Study of Izokibep in Non-infectious, Intermediate-, Posterior- or Pan-uveitis (clinicaltrials.gov) - P2 | N=96 | Active, not recruiting | Sponsor: ACELYRIN Inc. | Trial completion date: Aug 2025 ➔ Feb 2025 | Trial primary completion date: Aug 2025 ➔ Feb 2025

Trial completion date • Trial primary completion date • Ocular Inflammation • Ophthalmology • Uveitis