PRINCETON, N.J. and TOKYO, JAPAN — November 5, 2025 – Otsuka Pharmaceutical Development & Commercialization, Inc. (OPDC) and our parent company Otsuka Pharmaceutical Co. Ltd., (Otsuka) today announced that the first patients have been successfully enrolled and dosed in its Phase 3 clinical trial evaluating Quabodepistat, an investigational compound for the treatment of pulmonary multidrug-resistant tuberculosis (MDR-TB). TB, and particularly its resistant forms, remains a major global health challenge. According to the World Health Organization, 10 million people fall ill with tuberculosis each year, most of whom live in low- to middle-income countries. Despite being preventable and curable, 1.25 million people die from the disease annually.

The Phase 3 trial named QUANTUM-TB (Quabodepistat Accelerating New Treatments for Multidrug- Resistant Tuberculosis), is a randomized study designed to evaluate efficacy, safety, and tolerability of quabodepistat-containing regimens in adults and adolescents aged 14 and above. The primary goal of the quabodepistat clinical development program is to develop an efficacious, shorter-duration, less toxic, and well-tolerated regimen for treatment of people suffering from MDR-TB. The trial will compare a quabodepistat-based regimen administered for 17 weeks in participants with fluoroquinolone-sensitive MDR-TB and for 26 weeks in participants with fluoroquinolone-resistant MDR-TB against the corresponding WHO standards of care. The first participants were enrolled in the Philippines, marking a significant milestone in the development of this investigational compound. The trial is scheduled to be conducted at over 30 sites in several countries across the globe, including Japan.

“We are excited to begin this important trial and are deeply grateful to the participants and investigators,” said Masanori Kawasaki, senior vice president & operating officer, associate general manager (Research) at Otsuka. “This trial represents a critical step toward addressing the unmet needs of individuals suffering from drug-resistant TB.”

This Phase 3 clinical trial is registered on ClinicalTrials.gov under the identifier NCT07209761. More information about the trial can be found at https://clinicaltrials.gov/.