HUTCHMED (China) Limited (NASDAQ:HCM) disclosed on Tuesday encouraging results from the Phase 3 registration portion of its ongoing ESLIM-02 clinical trial assessing sovleplenib in adults diagnosed with warm antibody autoimmune hemolytic anemia (wAIHA). This condition arises when the immune system erroneously produces IgG antibodies that target and destroy red blood cells at normal body temperatures, thereby causing anemia alongside symptoms such as fatigue, pallor, and shortness of breath.
Within the China-based trial, the primary endpoint — measured as the durable hemoglobin (Hb) response rate between treatment weeks 5 and 24 — was successfully met, indicating sustained therapeutic benefit. Such findings mark a pivotal step in confirming sovleplenib’s clinical value in addressing this rare but serious hematological disorder.
Autoimmune hemolytic anemia (AIHA) presents an incidence rate estimated between 0.8 and 3.0 per 100,000 adult individuals annually, with an overall prevalence around 17 per 100,000 adults and a mortality range of 8 to 11 percent. Warm antibody AIHA comprises the majority of these cases, representing 75 to 80 percent of all adult AIHA diagnoses. ESLIM-02 functions as a Phase 2/3 trial focused specifically on adult patients who suffer from either primary or secondary wAIHA, who have previously been treated with at least one standard therapy line and demonstrated relapse or treatment resistance.
The earlier Phase 2 portion of ESLIM-02 yielded positive results that were published in The Lancet Haematology in January 2025. In that phase, sovleplenib demonstrated a significant hemoglobin improvement when compared to placebo, achieving an overall response rate of 43.8 percent in the initial eight weeks versus 0 percent in the placebo group. Furthermore, extending the treatment to a 24-week period, response rates for those receiving sovleplenib—including those crossing over from placebo—rose to 66.7 percent. Throughout the trial, sovleplenib also exhibited a favorable safety profile, reinforcing its potential as a viable treatment option.
Building on these clinical milestones, HUTCHMED intends to submit a New Drug Application (NDA) to the China National Medical Products Administration (NMPA) for sovleplenib’s use in wAIHA therapy during the first half of 2026. Additionally, sovleplenib is under investigation for another autoimmune condition, immune thrombocytopenia (ITP), with plans for an NDA resubmission in the second-line ITP category anticipated also in the same timeframe.
Competitive Environment
The competitive landscape for autoimmune blood disorder treatments remains active. In December 2025, Novartis AG (NYSE:NVS) released data from its VAYHIT2 Phase 3 trial evaluating a combination of ianalumab and eltrombopag in ITP patients who had prior corticosteroid therapy. Results indicated that the median time to treatment failure for patients treated with ianalumab plus eltrombopag was 13.0 months, notably 2.8 times longer than the 4.7 months observed in the placebo plus eltrombopag group.
In the same month, CRISPR Therapeutics AG (NASDAQ:CRSP) announced the commencement of a Phase 1 trial testing an allogeneic CAR T-cell therapy approach for both ITP and wAIHA. These developments underscore the robust investigational pipelines seeking to address unmet needs within these challenging autoimmune conditions.
Additional Clinical Initiatives
Beyond sovleplenib, HUTCHMED has recently initiated the Phase 3 portion of its Phase 2/3 trial assessing a combination regimen of surufatinib, camrelizumab, nab-paclitaxel, and gemcitabine. This study targets first-line treatment of metastatic pancreatic ductal adenocarcinoma patients in China, extending the company’s clinical development efforts across oncology indications.
Market Reaction
Following the announcement of the positive Phase 3 results, shares of HUTCHMED rose 5.09 percent to $14.45 during premarket trading on Wednesday. This movement reflects investor interest in the company’s advancing drug pipeline and potential regulatory achievements in the near future.