Itolizumab

Treatment with itolizumab did not improve complete or overall response rates at Day 29 Itolizumab achieved statistical significance in multiple secondary endpoints demonstrating compelling clinical benefit in longer-term outcomes, including complete response at Day 99, duration of complete response and failure-free survival Breakthrough Therapy designation and meeting requests to discuss potential for Accelerated Approval submitted to FDA, feedback expected during May 2025 Management will host a conference call and webcast today at 8:30 am ET LA JOLLA, CA, USA I March 27, 2025 I Equillium, Inc. (Nasdaq: EQ), a clinical-stage biotechnology company leveraging a deep understanding of immunobiology to develop novel therapeutics to treat severe autoimmune and inflammatory disorders, today announced topline data from the Phase 3 EQUATOR study evaluating itolizumab in first-line treatment of patients with acute graft-versus-host disease (aGVHD). The study results did not demonstrate a meaningful difference in complete response (CR) or overall response rate (ORR) at Day 29 between patients treated with itolizumab and placebo; however, statistically significant and clinically meaningful benefit in longer-term outcomes were achieved, including complete response at Day 99, duration of complete response and failure-free survival. Itolizumab exhibited a favorable safety and tolerability profile and did not increase the risk of clinical sequelae, including infection or sepsis, primary drivers of the high mortality associated with aGVHD. “While we did not observe improvements in Day 29 outcomes, itolizumab demonstrated compelling clinical results in several important longer-term outcomes, conferring potential patient benefit where there are no approved therapies,” said Bruce Steel, chief executive officer at Equillium. “Based on these data and prior FDA guidance, we have filed for Breakthrough Therapy designation and have been granted a meeting to discuss the potential for Accelerated Approval of itolizumab for first-line treatment of aGVHD, a rare disease where one-year mortality exceeds 40 percent and itolizumab has already received Orphan Drug and Fast Track designations. We expect feedback from the FDA during May and, if positive, we would plan to submit a biologics license application during the first half of 2026.” “The longer-term outcomes are important,” said Dr. John Koreth, Professor of Medicine, Dana-Farber Cancer Institute, Harvard Medical School. “There are no approvals in first-line therapy for aGVHD, and no drug candidates have been able to demonstrate efficacy beyond four weeks. To demonstrate statistical significance in pre-specified endpoints of duration of complete response and failure-free survival, compared to standard of care therapy, is clinically meaningful.” The Phase 3 EQUATOR study in first-line aGVHD demonstrated a favorable safety and tolerability profile, and clinically meaningful longer-term outcomes. There was no meaningful difference in CR or ORR, the primary endpoint and a key secondary endpoint of the study (respectively), at Day 29 between patients treated with itolizumab and placebo, but statistical significance was achieved in several critically important secondary endpoints demonstrating improvement in longer term outcomes: The safety profile observed in the EQUATOR study was consistent with that observed in previously reported studies of itolizumab, and itolizumab did not increase the risk of clinical sequelae, including rates of infection and sepsis. Webcast and Conference Call Management will host a conference call accompanied by a slide presentation to provide an overview of the data from the Phase 3 EQUATOR study in first-line aGVHD, for analysts and institutional investors, at 8:30 am ET today, March 27, 2025. To access the call, please dial (800) 715-9871 or (646) 307-1963 for international callers, and if needed provide conference ID number 2574379. A live webcast of the call will also be available on the company’s Investor Relations page . The webcast will be archived for 180 days. About Graft-Versus-Host Disease (GVHD) GVHD is a multisystem disorder that is a common complication of allogeneic hematopoietic stem cell transplants (allo-HSCT) caused by the transplanted immune system recognizing and attacking the recipient’s body. Symptoms of GVHD include rash, itching, skin discoloration, nausea, vomiting, diarrhea, and jaundice, as well as eye dryness and irritation. GVHD is the leading cause of non-relapse mortality in cancer patients receiving allo-HSCT, and its risk limits the number and type of patients receiving HSCT. GVHD results in high morbidity and mortality, with one year survival as low as 40%. There are no approved treatments for first-line aGVHD. About the EQUATOR Study The Phase 3, randomized, double-blind, placebo-controlled multicenter study ( NCT05263999 ) compared the efficacy and safety of intravenous administered itolizumab versus placebo (randomized 1:1) as a first-line therapy in 158 adult and adolescent patients with Grade III-IV aGVHD, or Grade II aGVHD with lower gastrointestinal involvement, in combination with high doses of corticosteroids, the current standard of care. The primary study endpoint was complete response rate (CR) at Day 29; key secondary endpoints included overall response rate (ORR) at Day 29 and rate of durable CR from Day 29 through Day 99. Additional secondary outcomes included CR at Day 99, duration of CR, failure free survival, and overall survival. Per the study protocol, patients received itolizumab within 3-days of the first administration of high-dose corticosteroids with a treatment period from Days 1-99, and a follow-up period from Days 100-365. Subjects received 2 mg/kg methylprednisolone or equivalent on Day 1 and were randomized in a 1:1 ratio to the following two treatment groups: The EQUATOR study remains ongoing with all patients having completed dosing, and 30 patients in the follow-up period per protocol. An independent data monitoring committee oversees the study and regularly reviews safety data. About Itolizumab Itolizumab is a clinical-stage, first-in-class anti-CD6 monoclonal antibody that selectively targets the CD6-ALCAM signaling pathway to downregulate pathogenic T effector cells while preserving T regulatory cells critical for maintaining a balanced immune response. This pathway plays a central role in modulating the activity and trafficking of T cells that drive a number of immuno-inflammatory diseases. About Equillium Equillium is a clinical-stage biotechnology company leveraging a deep understanding of immunobiology to develop novel therapeutics to treat severe autoimmune and inflammatory disorders with high unmet medical need. The company’s pipeline consists of several novel immunomodulatory assets and product platform targeting immuno-inflammatory pathways. For more information, visit www.equilliumbio.com . SOURCE: Equillium

Equillium ended last year with $22.6 million, a sum it expects to keep the lights on into the third quarter. \n Equillium’s phase 3 graft-versus-host disease (GVHD) trial has missed its primary endpoint and two key secondary objectives. But the biotech brushed off the setback, highlighting other secondary endpoints and post hoc analyses to make the case it could file for FDA approval next year.The study randomized 158 adults and adolescents with acute GVHD to receive the anti-CD6 antibody itolizumab or placebo. Equillium advanced itolizumab into the late-phase trial in the belief the antibody can inhibit T effector cells while preserving T regulatory cells. Ono Pharmaceutical dropped out of an alliance last year, leading cash-strapped Equillium to pause enrollment and bring forward the readout.Thursday, Equillium reported the complete response (CR) rate at Day 29 was 43% on itolizumab and 48.1% on placebo, causing the trial to miss its primary endpoint. Two key secondary endpoints looked at overall response rate at Day 29 and durable CR at Day 99. Neither result was statistically significant.The biotech reported significant improvements on the secondary endpoints median duration of CR—336 days for itolizumab versus 72 days for placebo—and failure-free survival. Post hoc analyses—durable CR evaluating Day 29 complete responders, and CR at Day 99 after removing three patients who did not receive any study treatment—also came out positive.  Itolizumab failed to improve overall survival. However, with the death rate favoring itolizumab, 24.4% playing off against 32.5%, Equillium added a “positive trend” in the data to its list of encouraging areas. Based on the data, Equillium has filed for breakthrough therapy designation and has secured a meeting with the FDA to discuss the potential for accelerated approval. The biotech expects to receive feedback from the agency in May. If the FDA offers encouragement, Equillium plans to file for approval in the first half of next year.  The biotech needs both the FDA and people with money to buy into its plan. Equillium ended last year with $22.6 million, a sum it expects to keep the lights on into the third quarter. Investors are skeptical, wiping 13% off the biotech’s stock in premarket trading to send the share price down to $0.66.