--- title: "Amlitelimab | PepTracker Pro" url: https://peptrackerpro.com/peptides/amlitelimab description: "Amlitelimab (SAR445229, formerly KY1005) is a fully human, non-T-cell-depleting monoclonal antibody from Sanofi that blocks OX40 ligand (OX40L), a costimulatory signal that drives and sustains T-cell-mediated inflammation. Rather than neutralizing a single cytokine like IL-4/IL-13 (dupilumab) or IL-5 (depemokimab), amlitelimab acts upstream at the OX40-OX40L checkpoint to dampen a broad, memory-driven inflammatory program without depleting T cells. Its lead (anchor) indication is moderate-to-severe atopic dermatitis in people aged 12 and older, where a distinctive feature is very infrequent dosing: after a loading dose it is given subcutaneously as little as four times a year (every 12 weeks). In the Phase 3 program - COAST 1, COAST 2 and SHORE - amlitelimab met its primary endpoints with EASI-75 and vIGA-AD 0/1 responses that increased over time, though COAST 2's absolute response rates were more modest and some observers called that readout mixed. Amlitelimab is investigational and not yet approved by any regulator; Sanofi originally gained it through its ~$1.1B acquisition of Kymab in 2021." lang: en --- Skip to main content **Educational information only.** This site does not provide medical advice. Read full disclaimer (https://peptrackerpro.com/disclaimer) **Research-only content.** This page is for educational purposes and does not constitute medical advice. Read full disclaimer → (https://peptrackerpro.com/research-disclaimer) # Amlitelimab High Evidence Amlitelimab (SAR445229, formerly KY1005) is a fully human, non-T-cell-depleting monoclonal antibody from Sanofi that blocks OX40 ligand (OX40L), a costimulatory signal that drives and sustains T-cell-mediated inflammation. Rather than neutralizing a single cytokine like IL-4/IL-13 (dupilumab) or IL-5 (depemokimab), amlitelimab acts upstream at the OX40-OX40L checkpoint to dampen a broad, memory-driven inflammatory program without depleting T cells. Its lead (anchor) indication is moderate-to-severe atopic dermatitis in people aged 12 and older, where a distinctive feature is very infrequent dosing: after a loading dose it is given subcutaneously as little as four times a year (every 12 weeks). In the Phase 3 program - COAST 1, COAST 2 and SHORE - amlitelimab met its primary endpoints with EASI-75 and vIGA-AD 0/1 responses that increased over time, though COAST 2's absolute response rates were more modest and some observers called that readout mixed. Amlitelimab is investigational and not yet approved by any regulator; Sanofi originally gained it through its ~$1.1B acquisition of Kymab in 2021. Aliases Amlitelimab +6 more Evidence High Evidence Last Updated 2026-09-23 Reading Time 8 min ## What It Is Amlitelimab (development codes SAR445229 and KY1005) is a fully human, non-depleting, noncytotoxic monoclonal antibody that targets OX40 ligand (OX40L, also called CD252 or TNFSF4). OX40L is expressed on antigen-presenting cells and other cells at sites of inflammation; its receptor, OX40 (CD134), is found on activated T cells. Engagement of OX40 by OX40L is a costimulatory 'second signal' that amplifies the activation, expansion and survival of effector and memory T cells across the T-helper spectrum (Th2, Th1, Th17 and Th22). By binding OX40L, amlitelimab blocks that costimulatory axis and is designed to turn down an overactive, T-cell-driven inflammatory response while leaving the T-cell pool itself intact - a mechanism deliberately distinct from cytokine-specific biologics and from T-cell-depleting antibodies. This upstream position is the conceptual pitch: interrupting a shared costimulatory checkpoint may quiet several inflammatory pathways at once and reset immune memory, potentially giving durable control with infrequent dosing. The anchor indication is moderate-to-severe atopic dermatitis (AD) in adolescents and adults aged 12 and older. Dosing is subcutaneous: a loading dose of 500 mg (250 mg for patients under 40 kg) followed by 250 mg maintenance (125 mg under 40 kg) given either every 4 weeks (Q4W) or every 12 weeks (Q12W); the Q12W schedule means as few as four maintenance injections per year, an unusually low burden for a biologic. Amlitelimab advanced through a Phase 2a study (STREAM-AD, NCT03754309) and a Phase 2b trial (published in the Journal of Allergy and Clinical Immunology in 2024) that highlighted maintenance of response after dosing stopped, into a large Phase 3 atopic dermatitis program. In COAST 1 (NCT06130566), a monotherapy trial of 601 patients aged 12+, at week 24 EASI-75 was reached by 35.9% (Q4W) and 39.1% (Q12W) versus 19.1% for placebo, and vIGA-AD 0/1 by 21.1% and 22.5% versus 9.2% (non-responder imputation), meeting all primary and key secondary endpoints. In COAST 2 (NCT06181435), 547 patients, week-24 vIGA-AD 0/1 was 25.3% (Q4W) and 25.7% (Q12W) versus 14.8% placebo, with EASI-75 of 41.8% and 40.5% versus 24.2%. In SHORE (NCT06224348), 596 patients dosed on top of topical corticosteroids, week-24 vIGA-AD 0/1 reached 28.7% (Q4W) and 32.3% (Q12W) versus 16.8% placebo, and EASI-75 48.1% and 46.8% versus 32.3%. A recurring theme across the program - and in the Phase 2 open-label long-term extension ATLANTIS (NCT05769777), where week-52 vIGA-AD 0/1 reached about 50% and EASI-75 about 77% - is that responses deepen over months rather than plateauing early, consistent with the drug's proposed effect on the underlying costimulatory memory. Additional Phase 3 studies (AQUA, NCT06241118; ESTUARY, NCT06407934) were reading out through 2026. Beyond dermatitis, amlitelimab is being explored across immune-mediated diseases including asthma, systemic sclerosis, celiac disease, alopecia areata and hidradenitis suppurativa, though a Phase 2 asthma study (TIDE-Asthma) had its top dose miss the primary exacerbation endpoint while a middle dose showed nominally significant reductions. Amlitelimab remains investigational and is not approved by the FDA or any other regulator; Sanofi acquired it via the 2021 purchase of Kymab (~$1.1 billion upfront). Also known as: Amlitelimab, SAR445229, KY1005, anti-OX40L monoclonal antibody, anti-OX40 ligand antibody, OX40L blocker (Sanofi), amlitelimab-Sanofi ## Regulatory Status Investigational - Phase 3 (not approved) Amlitelimab (SAR445229 / KY1005) is an investigational fully human anti-OX40L monoclonal antibody from Sanofi and is not approved by the FDA or any other regulatory agency for atopic dermatitis or any other indication. Sanofi obtained the antibody through its 2021 acquisition of Kymab (approximately $1.1 billion upfront). The anchor indication is moderate-to-severe atopic dermatitis in patients aged 12 and older, supported by the Phase 3 program COAST 1 (NCT06130566), COAST 2 (NCT06181435) and SHORE (NCT06224348), all of which met their primary endpoints (COAST 2 with more modest absolute responses), plus long-term extension data from ATLANTIS (NCT05769777) and additional studies AQUA (NCT06241118) and ESTUARY (NCT06407934). Dosing is subcutaneous - a 500 mg loading dose (250 mg under 40 kg) followed by 250 mg maintenance (125 mg under 40 kg) every 4 or 12 weeks. Sanofi has indicated it intends to pursue regulatory submissions in atopic dermatitis. The antibody is also in earlier-stage development for other immune-mediated diseases (asthma - where a Phase 2 study's top dose missed its primary endpoint - systemic sclerosis, celiac disease, alopecia areata and hidradenitis suppurativa). Amlitelimab should be regarded as an experimental biologic available only through authorized clinical trials. ## Why Researchers Study It Researchers study amlitelimab because it tests a different and potentially more durable way to treat immune-mediated inflammation: instead of blocking one cytokine downstream, it blocks OX40 ligand, a costimulatory signal that helps activate and sustain the memory T cells that drive chronic inflammation. The appeal of hitting this upstream checkpoint is twofold. First, because OX40-OX40L signaling feeds several T-helper programs at once (Th2, Th1, Th17, Th22), a single antibody might quiet a broad inflammatory response rather than one narrow pathway - relevant to diseases like atopic dermatitis that are not purely Type 2. Second, and most distinctively, amlitelimab is engineered so it does not deplete T cells, and its clinical data show responses that build over months and can persist after dosing, which supports an unusually infrequent maintenance schedule of as little as four subcutaneous injections a year. That combination - broad upstream action, non-depleting mechanism and low dosing burden - is what makes it a closely watched alternative to cytokine-specific biologics such as dupilumab (IL-4/IL-13) and the anti-IL-13 antibodies, and to the competing anti-OX40 receptor antibodies rocatinlimab and telazorlimab. Amlitelimab is also a test of the 'platform' idea in immunology: whether one costimulation blocker can be developed across atopic dermatitis, asthma, systemic sclerosis, celiac disease, alopecia areata and hidradenitis suppurativa. The atopic dermatitis Phase 3 program (COAST 1, COAST 2, SHORE) provides the pivotal efficacy and safety data, while the mixed asthma Phase 2 result is a reminder that an upstream mechanism does not automatically translate to every disease. ## Proposed Mechanisms - OX40 ligand (OX40L/CD252/TNFSF4) blockade: amlitelimab binds OX40L on antigen-presenting cells and prevents it from engaging OX40 (CD134) on activated T cells, interrupting a key costimulatory 'second signal.' - Broad, non-cytokine-specific dampening of T-cell inflammation: because the OX40-OX40L axis supports multiple T-helper programs (Th2, Th1, Th17, Th22), blocking it can reduce inflammation across pathways rather than neutralizing a single cytokine such as IL-4, IL-13 or IL-5. - Non-depleting, noncytotoxic design: amlitelimab is engineered to modulate T-cell activation without killing T cells, aiming to preserve the immune repertoire while reducing pathological activation. - Effect on memory T cells and durability: by limiting costimulation-dependent expansion and survival of effector/memory T cells, the antibody is proposed to reset overactive immune memory, consistent with responses that deepen over time and persist after dosing. - Infrequent dosing rationale: durable pharmacodynamic effects underpin subcutaneous maintenance dosing as far apart as every 12 weeks (about four injections per year) after a loading dose. - Platform potential across immune-mediated diseases: the same upstream mechanism is being tested in asthma, systemic sclerosis, celiac disease, alopecia areata and hidradenitis suppurativa, on the hypothesis that OX40L blockade is disease-agnostic where T-cell costimulation drives pathology. ## Evidence Snapshot High Evidence Low Medium High | Study Type | Model | Outcome | Link | | --- | --- | --- | --- | | Phase 2a randomized, double-blind, placebo-controlled trial (STREAM-AD, NCT03754309) in moderate-to-severe atopic dermatitis. | Adults with moderate-to-severe atopic dermatitis randomized to subcutaneous amlitelimab or placebo, with a post-treatment follow-up period. | Amlitelimab improved EASI and other AD measures versus placebo and was well tolerated (noncytotoxic, non-depleting anti-OX40L), with responses maintained for weeks after the last dose - establishing proof of concept and the durability signal that shaped later dosing. | Source | | Phase 2b randomized, double-blind, placebo-controlled dose-ranging trial (published in the Journal of Allergy and Clinical Immunology, 2024). | Patients with moderate-to-severe atopic dermatitis across multiple amlitelimab dose arms versus placebo, including a maintenance/withdrawal assessment. | Confirmed dose-related efficacy on EASI-75 and IGA endpoints and, notably, maintenance of response after dosing, supporting infrequent (up to Q12W) subcutaneous dosing and advancement to Phase 3. | Source | | Phase 3 pivotal monotherapy trials COAST 1 (NCT06130566) and COAST 2 (NCT06181435) in patients aged 12+ with moderate-to-severe atopic dermatitis. | Randomized, double-blind, placebo-controlled, 3-arm studies (amlitelimab Q4W, amlitelimab Q12W, placebo) after a 500 mg loading dose; COAST 1 enrolled 601 and COAST 2 547 participants; primary endpoints EASI-75 and vIGA-AD 0/1 at week 24. | COAST 1 met all primary and key secondary endpoints (week-24 EASI-75 35.9% Q4W / 39.1% Q12W vs 19.1% placebo; vIGA-AD 0/1 21.1% / 22.5% vs 9.2%, NRI). COAST 2 met its primary endpoint with more modest absolute responses (vIGA-AD 0/1 25.3% / 25.7% vs 14.8%; EASI-75 41.8% / 40.5% vs 24.2%), a readout some observers characterized as mixed. | Source | | Phase 3 combination trial SHORE (NCT06224348) with background topical corticosteroids, plus long-term extension ATLANTIS (NCT05769777). | SHORE randomized 596 patients aged 12+ to amlitelimab Q4W or Q12W or placebo on top of topical corticosteroids; ATLANTIS is an open-label long-term study (about 963 patients) assessing durability. | SHORE met its endpoints at week 24 (vIGA-AD 0/1 28.7% Q4W / 32.3% Q12W vs 16.8% placebo; EASI-75 48.1% / 46.8% vs 32.3%). In ATLANTIS, responses continued to deepen, reaching roughly vIGA-AD 0/1 ~50% and EASI-75 ~77% by week 52, reinforcing the 'progressive efficacy' pattern; overall tolerability was favorable across the program. | Source | ## Commonly Discussed Benefits Inflammation: https://peptrackerpro.com/benefits/inflammation Immune Modulation: https://peptrackerpro.com/benefits/immune-modulation Skin: https://peptrackerpro.com/benefits/skin type-2-inflammation: https://peptrackerpro.com/benefits/type-2-inflammation Researching Amlitelimab? Track it, set reminders, and keep notes in the free app. Track in App (https://app.peptrackerpro.com/?add=amlitelimab) ## Safety & Cautions - Amlitelimab is an investigational biologic that is NOT approved by the FDA or any regulator for atopic dermatitis or any other condition. It is studied only within clinical trials under medical supervision; any product sold as 'amlitelimab', 'SAR445229' or 'KY1005' outside a legitimate trial is unverified and should not be used. - Across the atopic dermatitis trials amlitelimab was generally well tolerated, with overall adverse-event rates similar between amlitelimab and placebo; injection-site reactions were uncommon and mild (about 2.2% vs 0.7% for placebo), and the most frequent events (atopic dermatitis flare, nasopharyngitis, upper respiratory tract infection) tended to occur more often in placebo groups. - As an immunomodulatory antibody that dampens T-cell costimulation, class-level considerations include a theoretical risk of infection and blunted responses to vaccines; long-term immune-safety data are still accumulating. - Efficacy is real but partial: in the pivotal trials only a minority of patients reached vIGA-AD 0/1 (clear/almost-clear skin) at week 24, absolute response rates in COAST 2 were modest, and responses tend to deepen over months, so the drug should not be presented as clearing most patients quickly. - Evidence outside atopic dermatitis is early or unproven - a Phase 2 asthma study missed its primary endpoint at the top dose - so benefits in asthma, systemic sclerosis, celiac disease, alopecia areata and hidradenitis suppurativa remain hypotheses under investigation. - This profile is educational information about a compound under clinical investigation, not medical advice; decisions about treating atopic dermatitis or any inflammatory disease should be made with a qualified clinician. ## Comparisons See how Amlitelimab compares to related peptides: Amlitelimab vs Efzofitimod: https://peptrackerpro.com/compare/amlitelimab-vs-efzofitimod Amlitelimab vs Icotrokinra (ICOTYDE): https://peptrackerpro.com/compare/amlitelimab-vs-icotrokinra Amlitelimab vs Rozanolixizumab: https://peptrackerpro.com/compare/amlitelimab-vs-rozanolixizumab Amlitelimab vs Depemokimab: https://peptrackerpro.com/compare/amlitelimab-vs-depemokimab Amlitelimab vs Barzolvolimab: https://peptrackerpro.com/compare/amlitelimab-vs-barzolvolimab Amlitelimab vs Frexalimab: https://peptrackerpro.com/compare/amlitelimab-vs-frexalimab Amlitelimab vs Rocatinlimab: https://peptrackerpro.com/compare/amlitelimab-vs-rocatinlimab ## Calculator Tools Use our research tools to explore dosing and reconstitution data: Reconstitution Calculator: https://peptrackerpro.com/calculators ## Citations 1. [1] Sanofi's amlitelimab met all primary and key secondary endpoints in the COAST 1 phase 3 study in atopic dermatitis (September 2025) - Sanofi PubMed (https://www.sanofi.com/en/media-room/press-releases/2025/2025-09-04-05-00-00-3144170) 2. [2] Sanofi's amlitelimab confirms its potential in atopic dermatitis (COAST 2 and SHORE, January 2026) - Sanofi PubMed (https://www.sanofi.com/en/media-room/press-releases/2026/2026-01-23-06-00-00-3224400) 3. [3] AAD: new results from Sanofi's amlitelimab phase 3 studies in atopic dermatitis presented in late-breaking research session (March 2026) - Sanofi PubMed (https://www.sanofi.com/en/media-room/press-releases/2026/2026-03-28-15-00-00-3264184) 4. [4] COAST 1 - A Study to Evaluate Amlitelimab in Participants Aged 12 Years and Older With Moderate-to-Severe Atopic Dermatitis - ClinicalTrials.gov NCT06130566 PubMed (https://clinicaltrials.gov/study/NCT06130566) 5. [5] SHORE - A Study of Amlitelimab With Topical Corticosteroids in Moderate-to-Severe Atopic Dermatitis - ClinicalTrials.gov NCT06224348 PubMed (https://clinicaltrials.gov/study/NCT06224348) 6. [6] Phase 2b randomized clinical trial of amlitelimab, an anti-OX40 ligand antibody, in patients with moderate-to-severe atopic dermatitis - Journal of Allergy and Clinical Immunology (2024) PubMed (https://www.jacionline.org/article/S0091-6749(24)01175-8/fulltext) 7. [7] Sanofi to Acquire Kymab, Adding KY1005 (amlitelimab) to Pipeline (2021) - Sanofi PubMed (https://www.sanofi.com/en/media-room/press-releases/2021/2021-01-11-07-30-00-2155914) 8. [8] Sanofi to seek approval of touted eczema drug despite mixed results - BioPharma Dive PubMed (https://www.biopharmadive.com/news/sanofi-amlitelimab-eczema-atopic-dermatitis-drug-results/810353/) ### Keep researching in the app - Log Amlitelimab to your private tracker - Set a dosing reminder - Compare it side-by-side with your stack Open PepTracker Pro Free: https://app.peptrackerpro.com/?add=amlitelimab Browse more peptides: https://peptrackerpro.com/peptides ## Related Peptides ### Efzofitimod Medium Evidence A first-in-class, intravenous immunomodulatory fusion peptide derived from histidyl-tRNA synthetase that selectively binds neuropilin-2 (NRP2) to dampen inflammation in the lung; in Phase 3 development for pulmonary sarcoidosis, an interstitial lung disease. Inflammation: https://peptrackerpro.com/benefits/inflammation Immune Support: https://peptrackerpro.com/benefits/immune-support View Details: https://peptrackerpro.com/peptides/efzofitimod \+ Compare: https://peptrackerpro.com/compare?select=efzofitimod Track in App: https://app.peptrackerpro.com/?add=efzofitimod ### Icotrokinra (ICOTYDE) High Evidence The first FDA-approved targeted oral macrocyclic peptide — an IL-23 receptor antagonist for moderate-to-severe plaque psoriasis, marking a new era for oral peptide therapeutics. Skin: https://peptrackerpro.com/benefits/skin Inflammation: https://peptrackerpro.com/benefits/inflammation Immune Support: https://peptrackerpro.com/benefits/immune-support View Details: https://peptrackerpro.com/peptides/icotrokinra \+ Compare: https://peptrackerpro.com/compare?select=icotrokinra Track in App: https://app.peptrackerpro.com/?add=icotrokinra ### Rozanolixizumab High Evidence Rozanolixizumab (brand name Rystiggo, development code UCB7665) is a humanized IgG4 monoclonal antibody that blocks the neonatal Fc receptor (FcRn), developed by UCB. Like efgartigimod and nipocalimab it lowers circulating immunoglobulin G (IgG) - including the pathogenic autoantibodies that drive many autoimmune diseases - by binding FcRn and preventing it from recycling IgG back into the blood, so unrescued IgG is routed to the lysosome and degraded, typically cutting total IgG by roughly 70-80% while sparing IgM, IgA, complement, and albumin. Unlike efgartigimod's engineered Fc fragment, rozanolixizumab is a full-length humanized antibody, and unlike nipocalimab's intravenous infusion it is given as a rapid subcutaneous infusion (including via an on-body delivery device), typically in weekly cycles that are repeated based on clinical response rather than continuously. The FDA approved Rystiggo on June 27, 2023 for generalized myasthenia gravis (gMG) in adults who are anti-acetylcholine-receptor (AChR) antibody-positive or anti-muscle-specific-tyrosine-kinase (MuSK) antibody-positive - making it the first therapy ever approved to treat both of those gMG subtypes - on the strength of the Phase 3 MycarinG trial. It has since been studied across other IgG-mediated diseases, including chronic inflammatory demyelinating polyneuropathy (CIDP), where it did not show meaningful benefit and was not advanced to Phase 3, and myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD), primary immune thrombocytopenia (ITP), and other autoantibody conditions where development continues. The European Medicines Agency approved rozanolixizumab in January 2024 and the UK MHRA in March 2024. Immune Modulation: https://peptrackerpro.com/benefits/immune-modulation Neuromuscular Function: https://peptrackerpro.com/benefits/neuromuscular-function Rare Disease Treatment: https://peptrackerpro.com/benefits/rare-disease-treatment Disease Modification: https://peptrackerpro.com/benefits/disease-modification View Details: https://peptrackerpro.com/peptides/rozanolixizumab \+ Compare: https://peptrackerpro.com/compare?select=rozanolixizumab Track in App: https://app.peptrackerpro.com/?add=rozanolixizumab ### Depemokimab High Evidence Depemokimab (brand name Exdensur; nonproprietary name depemokimab-ulaa; development code GSK3511294) is a humanized, affinity-matured IgG1 monoclonal antibody that blocks interleukin-5 (IL-5), the master cytokine for eosinophils - the white blood cells that drive type 2 (eosinophilic) inflammation in severe asthma and related diseases. Developed by GSK, it is the first ultra-long-acting IL-5 biologic, engineered both for very high IL-5 binding affinity (roughly 29-fold more potent than mepolizumab in vitro) and with a triple-amino-acid 'YTE' modification in its Fc region that extends its half-life, enabling a fixed 100 mg subcutaneous injection just twice a year (once every 26 weeks). By neutralizing IL-5 before it can reach the IL-5 receptor on eosinophils, depemokimab lowers blood and airway eosinophils and reduces the flare-ups (exacerbations) that define severe eosinophilic asthma. In the pivotal Phase 3 SWIFT-1 and SWIFT-2 trials, twice-yearly depemokimab cut annualized asthma exacerbations by roughly half versus placebo over 52 weeks (58% in SWIFT-1, 48% in SWIFT-2), with a pooled ~72% reduction in exacerbations requiring hospitalization or emergency care. On the strength of those data, the U.S. FDA approved Exdensur in December 2025 as an add-on maintenance treatment for severe asthma with an eosinophilic phenotype in patients aged 12 and older, and it is also being developed - and, in China, approved - for chronic rhinosinusitis with nasal polyps (CRSwNP). Depemokimab is a prescription biologic given under medical care; it is not a supplement, nootropic, or research chemical. anti-inflammatory: https://peptrackerpro.com/benefits/anti-inflammatory respiratory: https://peptrackerpro.com/benefits/respiratory Immune Modulation: https://peptrackerpro.com/benefits/immune-modulation type-2-inflammation: https://peptrackerpro.com/benefits/type-2-inflammation View Details: https://peptrackerpro.com/peptides/depemokimab \+ Compare: https://peptrackerpro.com/compare?select=depemokimab Track in App: https://app.peptrackerpro.com/?add=depemokimab ### Barzolvolimab Medium Evidence Barzolvolimab (development code CDX-0159) is an investigational humanized IgG1 monoclonal antibody from Celldex Therapeutics that works by a mechanism new to allergy and dermatology: it depletes mast cells. It binds with high specificity to the KIT receptor (CD117), a receptor tyrosine kinase that mast cells depend on for their growth, survival and activation, and blocks KIT from being switched on by its natural ligand, stem cell factor (SCF). Because mast cells cannot survive without KIT signaling, blocking the receptor lowers mast-cell numbers throughout the body - an effect visible as a dose-dependent fall in blood tryptase (a mast-cell marker) and a drop in mast cells in the skin. Mast cells are the central drivers of chronic urticaria (chronic hives): when they release histamine and other mediators they cause the wheals, angioedema and itch that define the disease, so removing the cells themselves is a more upstream approach than blocking a single downstream signal. Barzolvolimab's lead program is chronic spontaneous urticaria (CSU) that no longer responds to antihistamines, where it is being tested in two large replicate Phase 3 trials, EMBARQ-CSU1 and EMBARQ-CSU2, which together enrolled 1,939 patients - the largest Phase 3 program ever run in antihistamine-refractory CSU - with topline results expected in late 2026 and a planned regulatory (BLA) filing in 2027. It has also shown strong Phase 2 results in the chronic inducible urticarias - cold urticaria and symptomatic dermographism - and is being explored in prurigo nodularis, atopic dermatitis and eosinophilic esophagitis. Barzolvolimab is an investigational biologic given by subcutaneous injection under clinical-trial or specialist supervision; it is not approved, and it is not a supplement, nootropic or research chemical. Inflammation: https://peptrackerpro.com/benefits/inflammation Immune Modulation: https://peptrackerpro.com/benefits/immune-modulation Skin: https://peptrackerpro.com/benefits/skin View Details: https://peptrackerpro.com/peptides/barzolvolimab \+ Compare: https://peptrackerpro.com/compare?select=barzolvolimab Track in App: https://app.peptrackerpro.com/?add=barzolvolimab ### Frexalimab High Evidence Frexalimab (SAR441344) is an investigational second-generation, fully human monoclonal antibody from Sanofi that blocks CD40 ligand (CD40L, also called CD154), a costimulatory 'second signal' that helps activate B cells, T cells and antigen-presenting cells and drives adaptive autoimmunity. Rather than depleting immune cells, frexalimab interrupts the CD40-CD40L checkpoint upstream - a mechanism related to but distinct from the OX40-OX40L blockade of amlitelimab. Its lead indication is relapsing multiple sclerosis (RMS), with a second program in nonrelapsing secondary progressive MS (nrSPMS). In the Phase 2 relapsing-MS trial (NCT04879628, published in the New England Journal of Medicine in 2024), frexalimab cut the number of new gadolinium-enhancing brain lesions at week 12 by 89% (higher-dose IV arm) and 79% (lower-dose subcutaneous arm) versus placebo, and open-label extensions out to two and three years show that disease control and reductions in neurofilament light have been sustained. Crucially, frexalimab is engineered so its Fc region does not activate platelets, which is designed to avoid the thromboembolic complications that halted first-generation anti-CD40L antibodies decades ago. It is now in the Phase 3 FREXALT (relapsing MS, versus teriflunomide) and FREVIVA (nrSPMS, versus placebo) trials, with additional Phase 2 programs in type 1 diabetes (FABULINUS) and systemic lupus erythematosus; a Sjogren's syndrome study was discontinued in 2024 after it fell short on efficacy. Frexalimab is investigational and not approved by any regulator. Immune Modulation: https://peptrackerpro.com/benefits/immune-modulation Inflammation: https://peptrackerpro.com/benefits/inflammation autoimmune: https://peptrackerpro.com/benefits/autoimmune Disease Modification: https://peptrackerpro.com/benefits/disease-modification View Details: https://peptrackerpro.com/peptides/frexalimab \+ Compare: https://peptrackerpro.com/compare?select=frexalimab Track in App: https://app.peptrackerpro.com/?add=frexalimab ### Rocatinlimab High Evidence Rocatinlimab (AMG 451 / KHK4083) is an investigational anti-OX40 monoclonal antibody developed by Kyowa Kirin and Amgen for moderate-to-severe atopic dermatitis (eczema). Unlike amlitelimab, which blocks the OX40 ligand (OX40L) on antigen-presenting cells without depleting cells, rocatinlimab binds the OX40 receptor directly on activated pathogenic T cells and reduces (depletes) them - a 'T-cell rebalancing' approach meant to reset the immune drivers of chronic inflammation rather than continuously neutralize a single cytokine. In the large Phase 3 ROCKET program the drug met its co-primary endpoints: in ROCKET-IGNITE (NCT05398445; 769 adults, added to topical therapy) week-24 EASI-75 reached about 42% (higher dose) and 36% (lower dose) versus roughly 13% on placebo, and vIGA-AD 0/1 reached about 24% and 19%; in the ROCKET-HORIZON monotherapy study (NCT05651711) EASI-75 was about 33% versus 14% on placebo, though the drug showed no superiority over dupilumab. The pooled Phase 3 results were published in The Lancet in 2025. Despite hitting its endpoints, the program then unraveled on two fronts: in January 2026 Amgen ended the collaboration on strategic-portfolio grounds and returned global rights to Kyowa Kirin, and on March 3, 2026 Kyowa Kirin discontinued ALL rocatinlimab clinical trials - across atopic dermatitis, prurigo nodularis and uncontrolled asthma - after a safety review identified cases of Kaposi's sarcoma (one newly confirmed and one suspected, in addition to a previously confirmed case) that suggested a possible mechanistic link to OX40-pathway modulation. Rocatinlimab is investigational, was never approved by any regulator, and its clinical development has been halted. View Details: https://peptrackerpro.com/peptides/rocatinlimab \+ Compare: https://peptrackerpro.com/compare?select=rocatinlimab Track in App: https://app.peptrackerpro.com/?add=rocatinlimab ## Structured data ```json [ { "@context": "https://schema.org", "@type": "Organization", "name": "PepTracker Pro", "url": "https://peptrackerpro.com", "logo": "https://peptrackerpro.com/favicon.png", "description": "Evidence-based educational resource dedicated to improving peptide research literacy.", "contactPoint": { "@type": "ContactPoint", "email": "hello@peptrackerpro.com", "contactType": "customer support" }, "sameAs": [] }, { "@context": "https://schema.org", "@type": "MedicalWebPage", "name": "Amlitelimab", "description": "Amlitelimab (SAR445229, formerly KY1005) is a fully human, non-T-cell-depleting monoclonal antibody from Sanofi that blocks OX40 ligand (OX40L), a costimulatory signal that drives and sustains T-cell-mediated inflammation. 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Amlitelimab (SAR445229, formerly KY1005) is a fully human, non-T-cell-depleting monoclonal antibody from Sanofi that blocks OX40 ligand (OX40L), a costimulatory signal that drives and sustains T-cell-mediated inflammation. Rather than neutralizing a single cytokine like IL-4/IL-13 (dupilumab) or IL-5 (depemokimab), amlitelimab acts upstream at the OX40-OX40L checkpoint to dampen a broad, memory-driven inflammatory program without depleting T cells. Its lead (anchor) indication is moderate-to-severe atopic dermatitis in people aged 12 and older, where a distinctive feature is very infrequent dosing: after a loading dose it is given subcutaneously as little as four times a year (every 12 weeks). In the Phase 3 program - COAST 1, COAST 2 and SHORE - amlitelimab met its primary endpoints with EASI-75 and vIGA-AD 0/1 responses that increased over time, though COAST 2's absolute response rates were more modest and some observers called that readout mixed. 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Its lead (anchor) indication is moderate-to-severe atopic dermatitis in people aged 12 and older, where a distinctive feature is very infrequent dosing: after a loading dose it is given subcutaneously as little as four times a year (every 12 weeks). In the Phase 3 program - COAST 1, COAST 2 and SHORE - amlitelimab met its primary endpoints with EASI-75 and vIGA-AD 0/1 responses that increased over time, though COAST 2's absolute response rates were more modest and some observers called that readout mixed. Amlitelimab is investigational and not yet approved by any regulator; Sanofi originally gained it through its ~$1.1B acquisition of Kymab in 2021." } }, { "@type": "Question", "name": "Investors and industry analysts following Sanofi's immunology pipeline and the value created by its 2021 Kymab acquisition?", "acceptedAnswer": { "@type": "Answer", "text": "Amlitelimab is a research peptide studied in preclinical models. 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Its lead (anchor) indication is moderate-to-severe atopic dermatitis in people aged 12 and older, where a distinctive feature is very infrequent dosing: after a loading dose it is given subcutaneously as little as four times a year (every 12 weeks). In the Phase 3 program - COAST 1, COAST 2 and SHORE - amlitelimab met its primary endpoints with EASI-75 and vIGA-AD 0/1 responses that increased over time, though COAST 2's absolute response rates were more modest and some observers called that readout mixed. Amlitelimab is investigational and not yet approved by any regulator; Sanofi originally gained it through its ~$1.1B acquisition of Kymab in 2021." } } ] } ] ```