HUTCHMED Completes Patient Enrollment of ESLIM-01, a Phase III Trial of Sovleplenib in Primary Immune Thrombocytopenia in China

Hong Kong, Shanghai & Florham Park, NJ — Tuesday, January 3, 2023: HUTCHMED (China) Limited (“HUTCHMED”) (Nasdaq/AIM:​HCM, HKEX:​13) today announces that it has completed patient enrollment of ESLIM-01, a pivotal Phase III clinical trial of sovleplenib for the treatment of adult patients with primary immune thrombocytopenia (“ITP”) in China. The last patient was enrolled on December 31, 2022.

The ESLIM-01 study, initiated in October 2021, is a randomized, double blinded, placebo-controlled Phase III clinical trial evaluating the efficacy and safety of sovleplenib in treating adult patients with ITP. The primary endpoint of the study is the durable response rate. Secondary and exploratory endpoints include overall response rate (ORR), incidence of treatment emergent adverse events, and patient quality of life improvement. A total of 188 patients were enrolled. Additional details may be found at clinicaltrials.gov, using identifier NCT05029635.

Topline results from the ESLIM-01 trial are expected to be reported in the second half of 2023, followed by submission of results for presentation at an appropriate medical congress. If positive, HUTCHMED would initiate plans to apply for marketing authorization of sovleplenib by the China National Medical Products Administration (NMPA).

About Sovleplenib

Sovleplenib is a novel, investigational, selective small molecule inhibitor for oral administration targeting the spleen tyrosine kinase, also known as Syk. Syk is a major component in B-cell receptor and Fc receptor signaling and is an established target for the treatment of multiple subtypes of B-cell lymphomas and autoimmune disorders.

HUTCHMED currently retains all rights to sovleplenib worldwide. In addition to ITP, sovleplenib is also being studied in warm antibody autoimmune hemolytic anemia (NCT05535933), indolent non-Hodgkin’s lymphoma and multiple subtypes of B-cell malignancies in China, the U.S. and Europe (NCT02857998; NCT03779113).

About ITP and Syk

ITP is an autoimmune disorder characterized by immunologic destruction of platelets and decreased platelet production. Patients with ITP exhibit symptoms of petechiae, purpura, and gastrointestinal and/or urinary mucosal tract bleeding.[i] ITP is also associated with fatigue (reported in up to 39% of adults with ITP) and impaired quality of life, across domains of emotional, functional and reproductive health, and work or social life.[ii]^{,[iii],[iv],[v],[vi]} The incidence of primary ITP in adults is 3.3/100,000 adults per year with a prevalence of 9.5 per 100,000 adults.[vii]

Adult ITP is a heterogeneous disease that can persist for years, even with best available care, and treatments are infrequently curative. Despite availability of several treatments with differing mechanisms of action, chronicity of disease continues to be a problem. Many patients develop resistance to treatment and thereby are prone to relapse.[viii] Thus, there remains a significant population of patients who have limited sensitivity to currently available agents and are in need of new treatments.

As platelet destruction in ITP is mediated by Syk-dependent phagocytosis of FcγR-bound platelets, Syk inhibition represents a promising approach to management of ITP.[ix]

About HUTCHMED

HUTCHMED (Nasdaq/AIM:​HCM; HKEX:​13) is an innovative, commercial-stage, biopharmaceutical company. It is committed to the discovery and global development and commercialization of targeted therapies and immunotherapies for the treatment of cancer and immunological diseases. It has more than 5,000 personnel across all its companies, at the center of which is a team of about 1,800 in oncology/​immunology. Since inception HUTCHMED has focused on bringing drug candidates from in-house discovery to patients around the world,  with its first three oncology drugs now approved and marketed in China. For more information, please visit: www.hutch‑med.com or follow us on LinkedIn.

[i] Zufferey A, Kapur R, Semple JW. Pathogenesis and Therapeutic Mechanisms in Immune Thrombocytopenia (ITP). J. Clin. Med. 2017, 6(2), 16.

[ii] McMillan R, Bussel JB, et al. Self-reported health-related quality of life in adults with chronic immune thrombocytopenic purpura. Am J Hematol. 2008 Feb;83(2):150-4.

[iii] Snyder CF, Mathias SD, Cella D, et al. Health-related quality of life of immune thrombocytopenic purpura patients: results from a web-based survey. Curr Med Res Opin. 2008 Oct;24(10):2767-76.

[iv] Doobaree IU, Nandigam R, Bennett D, et al. Thromboembolism in adults with primary immune thrombocytopenia: a systematic literature review and meta-analysis. Eur J Haematol. 2016 Oct;97(4):321-30.

[v] Sarpatwari A, Bennett D, Logie JW, et al. Thromboembolic events among adult patients with primary immune thrombocytopenia in the United Kingdom General Practice Research Database. Haematologica. 2010 Jul;95(7):1167-75.

[vi] Sarpatwari A, Watson S, Erqou S, et al. Health-related lifestyle in adults and children with primary immune thrombocytopenia (ITP). Br J Haematol. 2010 Oct;151(2):189-91.

[vii] Lambert MP, Gernsheimer TB. Clinical updates in adult immune thrombocytopenia. Blood. 2017 May 25;129(21):2829-2835.

[viii] Provan D, Arnold DM, Bussel JB, et al. Updated international consensus report on the investigation and management of primary immune thrombocytopenia. Blood Adv. 2019;3(22):3780-3817.

[ix] Crowley MT, Costello PS, Fitzer-Attas CJ et al. A critical role for Syk in signal transduction and phagocytosis mediated by Fcγ receptors on macrophages. J. Exp. Med. 186(7), 1027–1039 (1997).