• The Independent Data Monitoring Committee (IDMC) recommended continuation of the clinical trial based on safety assessment and pre-determined futility and efficacy stopping boundaries
• The results of the IDMC review have been delivered to Ono Pharmaceutical Co., Ltd. triggering the 90-day period to exercise its option to acquire Equillium’s rights to itolizumab for JPY 5 billion plus potential milestone payments

LA JOLLA, Calif. / Aug 06, 2024 / Business Wire / Equillium, Inc. (Nasdaq: EQ), a clinical-stage biotechnology company focused on developing novel therapeutics to treat severe autoimmune and inflammatory disorders, today announced a positive recommendation from the Independent Data Monitoring Committee (IDMC) based on its review of the interim results from the Phase 3 EQUATOR study evaluating itolizumab in subjects with acute graft-versus-host disease (aGVHD). The IDMC reviewed unblinded data on over 100 patients through Day 29 of treatment from the study, with pre-determined futility and efficacy stopping boundaries, and recommended that the study proceed with continued enrollment, without modifications.

“We are pleased with the outcome of the interim review where the Independent Data Monitoring Committee did not raise any safety or futility concerns and recommended that the Phase 3 EQUATOR study continue as planned,” said Bruce Steel, chief executive officer at Equillium. “We have over 100 clinical sites worldwide enrolling patients and look forward to completing the study expeditiously. We believe that itolizumab may demonstrate a significant benefit for patients suffering from acute graft-versus-host disease, where mortality rates are very high and first-line standard of care remains high-dose corticosteroids. The blinded interim data along with the IDMC recommendation has been delivered to our partner, Ono Pharmaceutical, who has until the end of October 2024 to make its decision to acquire our rights to itolizumab, which would result in a one-time payment of JPY 5.0 billion, or approximately $35.0 million based on the currency exchange rate on August 5, 2024. Should Ono exercise its option, Equillium would also be eligible to receive up to USD $101.4 million upon the achievement of certain clinical, regulatory, and commercialization milestones.”

About the EQUATOR Study

The Phase 3, randomized, double-blind, placebo-controlled multicenter study (NCT05263999) compares the efficacy and safety of intravenous administered itolizumab versus placebo (randomized 1:1) as a first-line therapy in approximately 200 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 is complete response rate at Day 29; key secondary endpoints include overall response rate at Day 29 and durability of complete response rate from Day 29 through Day 99.

Per the study protocol, patients must receive 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. Approximately 200 eligible subjects will receive 2 mg/kg methylprednisolone or equivalent on Day 1 and will be randomized in a 1:1 ratio to the following two treatment groups:

1. Group A: Itolizumab, 1.6 mg/kg initial dose followed by 6 doses of 0.8 mg/kg once every 2 weeks (q2w), plus systemic corticosteroids (100 subjects)
2. Group B: Placebo, 7 doses q2w, plus systemic corticosteroids (100 subjects)

An independent data monitoring committee regularly reviews safety data, and an interim analysis for both futility and efficacy was conducted after approximately 100 subjects had completed Day 29 assessments.

About Itolizumab

Itolizumab is a clinical-stage, first-in-class anti-CD6 monoclonal antibody that selectively targets the CD6-ALCAM signaling pathway to selectively 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 the following novel first-in-class immunomodulatory assets and product platform targeting immuno-inflammatory pathways. EQ101: a selective tri-specific cytokine inhibitor targeting IL-2, IL-9, and IL-15; recently announced positive results from a Phase 2 proof-of-concept clinical study of patients with alopecia areata. EQ302: an orally delivered, selective bi-specific cytokine inhibitor targeting IL-15 and IL-21; currently in pre-clinical development. The multi-cytokine platform: generates rationally designed composite peptides that selectively block key cytokines at the shared receptor level targeting pathogenic cytokine redundancies and synergies while preserving non-pathogenic signaling. Itolizumab: a monoclonal antibody that targets the CD6-ALCAM signaling pathway which plays a central role in the modulation of effector T cells; currently under evaluation in a Phase 3 clinical study of patients with acute graft-versus-host disease (aGVHD) and announced positive data from a Phase 1b clinical study of patients with lupus/lupus nephritis in April 2024. Equillium acquired rights to itolizumab through an exclusive partnership with Biocon Limited and has entered a strategic partnership with Ono Pharmaceutical Co., Ltd. (Ono), for the development and commercialization of itolizumab under an option and asset purchase agreement.

For more information, visit www.equilliumbio.com.

Forward-Looking Statements

Statements contained in this press release regarding matters that are not historical facts are "forward-looking statements" within the meaning of the Private Securities Litigation Reform Act of 1995. Forward-looking statements may be identified by the use of words such as "anticipate," "believe," “could,” “continue,” "expect," "estimate," “may,” "plan," "outlook," “future” and "project" and other similar expressions that predict or indicate future events or trends or that are not statements of historical matters. These statements include, but are not limited to, statements regarding Equillium’s plans for developing EQ101, EQ302 and itolizumab; the expected timeline for results from clinical studies, the expected timing for Ono to make its decision regarding exercising its option and the potential consideration that may be payable to Equillium; and the potential benefits of Equillium’s product candidates. Because such statements are subject to risks and uncertainties, many of which are outside of Equillium’s control, actual results may differ materially from those expressed or implied by such forward-looking statements. Risks that contribute to the uncertain nature of the forward-looking statements include: Equillium’s ability to execute its plans and strategies; risks related to performing clinical and pre-clinical studies; whether the results from clinical and pre-clinical studies will validate and support the safety and efficacy of Equillium’s product candidates; changes in the competitive landscape; and risks related to Ono’s financial condition and decision to exercise its option, if ever, to purchase itolizumab, and the risk that Equillium may never receive any of the contingent consideration under the asset purchase agreement. These and other risks and uncertainties are described more fully under the caption "Risk Factors" and elsewhere in Equillium's filings and reports, which may be accessed for free by visiting the Securities and Exchange Commission’s website at www.sec.gov and on Equillium’s website under the heading “Investors.” Investors should take such risks into account and should not rely on forward-looking statements when making investment decisions. All forward-looking statements contained in this press release speak only as of the date on which they were made. Equillium undertakes no obligation to update such statements to reflect events that occur or circumstances that exist after the date on which they were made, except as required by law.