• More than 100 patients enrolled from over 100 clinical trial sites active in 12 countries
• Delivery of the interim data review to Ono Pharmaceutical Co. Ltd. (Ono) expected during Q3 will trigger Ono’s option exercise period

LA JOLLA, Calif. / May 14, 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 that it has surpassed the interim enrollment target for the Phase 3 EQUATOR study of itolizumab in acute graft-versus-host disease (aGVHD). Equillium expects to deliver the results of the EQUATOR interim data review to Ono during the third quarter, which will then trigger Ono’s three-month option exercise period to acquire Equillium’s rights to itolizumab.

“Our clinical development team has done an excellent job of recruiting and activating trial sites globally,” said Bruce Steel, chief executive officer at Equillium. “While the interim data will be blinded to Equillium and Ono, our independent data monitoring committee will conduct an unblinded analysis of the data and make a recommendation whether the study should proceed to conclusion based on pre-determined futility and efficacy stopping boundaries. Having now met the enrollment threshold for the interim review, we believe we are well on track to meet our guidance of delivering this final data milestone to Ono during the third quarter, setting the timeline for Ono’s option exercise decision to acquire itolizumab, which will expire three months following delivery of the results of the interim analysis.”

If Ono exercises the option, Ono will pay Equillium a one-time payment of JPY 5.0 billion, or approximately $32.2 million based on the currency exchange rate on May 8, 2024. Equillium is also eligible to receive up to $101.4 million upon the achievement of certain development, regulatory, and commercialization milestones.

About the EQUATOR Study

The Phase 3, randomized, double-blind, placebo-controlled multicenter study (NCT05263999) will compare the efficacy and safety of IV 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 GI 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 will regularly review safety data, and an interim analysis for both futility and efficacy will be conducted after approximately 100 subjects have 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; currently under evaluation in a Phase 2 proof-of-concept clinical study of patients with alopecia areata being conducted in Australia and New Zealand by Equillium’s Australian subsidiary as the trial sponsor. 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 recently completed a Phase 1b clinical study of patients with lupus/lupus nephritis. Equillium acquired rights to itolizumab through an exclusive partnership with Biocon Limited and has entered a strategic partnership with Ono Pharmaceutical Co., Ltd., 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 to deliver the results of the interim review of the EQUATOR study to Ono Pharmaceutical and related timing thereof, the timing for triggering Ono’s option period and for receiving Ono’s option decision, plans for developing EQ101, EQ302 and itolizumab, the expected timeline for results from clinical studies, anticipated upcoming milestones, the fluctuation of the foreign exchange rate, 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; Equillium’s plans and product development, including the initiation and completion of clinical studies and the reporting of data therefrom; changes in the competitive landscape; risks related to Ono’s financial condition and decision to exercise its option, if ever, to purchase itolizumab or terminate the asset purchase agreement; and uncertainties related to Equillium’s capital requirements. 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 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.