Takeda announces positive results for mezagitamab in Phase 2 ITP study

Takeda Pharmaceutical Company Limited has disclosed favorable top-line outcomes from a Phase 2, randomized, double-blind, placebo-controlled trial, assessing the safety, tolerability, and efficacy of mezagitamab (TAK-079) in individuals with persistent or chronic primary immune thrombocytopenia (ITP). The study, known as TAK-079-1004 (NCT04278924), explored the impact of three different doses of subcutaneous mezagitamab versus placebo, administered weekly for eight weeks, on patients with chronic (lasting more than a year) or persistent (3-12 months) primary ITP. This interim analysis of the ongoing Phase 2 study revealed that mezagitamab was generally safe and well-tolerated across all cohorts, with all doses tested showing a higher platelet response rate compared to placebo.

Mezagitamab is a fully human immunoglobulin IgG1 monoclonal antibody (mAb) targeting CD38 expressing cells, including plasmablasts, plasma cells, and natural killer cells, leading to their depletion. This mechanism of action offers a novel approach to treating ITP, a rare autoimmune disorder characterized by the accelerated destruction of platelets, leading to a heightened risk of bleeding. Approximately 20% of ITP patients do not achieve a sufficient platelet count with current first- and second-line therapies, highlighting a significant unmet need for more effective and tolerable treatments.

The study’s results demonstrated a dose-dependent increase in platelet counts, with the greatest response observed at the highest dose. Remarkably, platelet response in patients treated with mezagitamab occurred rapidly and was sustained post-therapy, indicating its potential as a disease-modifying treatment. Based on these findings, Takeda is planning to initiate a global Phase 3 trial of mezagitamab in ITP in fiscal year 2024, signaling a significant step forward in addressing the unmet needs of this patient population.

Chinwe Ukomadu, Head of the Gastrointestinal & Inflammation Therapeutic Area Unit at Takeda, commented on the results, stating, “These Phase 2 results demonstrate mezagitamab’s compelling disease-modifying mechanism of action, which has the potential to achieve disease remission for people with ITP. There remains considerable unmet need among ITP patients who may not respond or have inadequate response to prior treatment.” The enthusiasm for initiating the Phase 3 trial reflects Takeda’s commitment to advancing care for individuals with ITP.

Moreover, mezagitamab has already garnered Orphan Drug Designation from the U.S. Food and Drug Administration for the treatment of ITP, with the program also receiving Fast Track Designation recently. This recognition underscores the potential impact of mezagitamab on treating ITP and Takeda’s broader efforts to develop innovative therapies for challenging medical conditions.

Takeda’s announcement of positive Phase 2 results for mezagitamab marks an important milestone in the development of new treatments for ITP. As the company prepares to launch a global Phase 3 trial, the ITP community remains hopeful for a new therapeutic option that can address the significant challenges faced by patients. Takeda’s progress in its late-stage pipeline, including mezagitamab, demonstrates the company’s ongoing dedication to discovering and delivering life-changing treatments.