Taiho’s Investigational DMD Therapy Misses Primary Endpoint in Phase 3 Trial

Taiho Pharmaceutical's investigational treatment for Duchenne muscular dystrophy (DMD), TAS-205 (pizuglanstat), failed to meet the primary endpoint in a Phase 3 trial, showing no significant improvement in the time to rise from the floor after 52 weeks in the ambulatory cohort of male patients aged 5 years and older.135

The REACH-DMD study was a randomized, placebo-controlled, double-blind trial conducted in Japan involving 82 patients; the primary endpoint focused on the mean change from baseline for the time it takes patients to get up from the ground.15

Both trial cohorts—ambulatory and non-ambulatory—have been discontinued following the negative results.1

Further detailed findings from the study are expected to be presented at an upcoming academic conference.14

TAS-205 is designed to selectively inhibit the enzyme hematopoietic prostaglandin D synthase (HPGDS), intended as an anti-inflammatory approach for DMD regardless of the dystrophin gene mutation type.14

The trial setback led to a nearly 2% drop in shares of Taiho’s parent company, Otsuka Holdings, on July 8, 2025.25

Sources:

1. https://www.fiercebiotech.com/biotech/taihos-dmd-asset-fails-improve-functional-motor-test-results-phase-3-trial

2. https://www.thepharmaletter.com/pharmaceutical/taiho-suffers-setback-with-dmd-hopeful

3. https://www.bioworld.com/articles/721912-taihos-pizuglanstat-fails-in-phase-iii-dmd-trial

4. https://dmdwarrior.com/taiho-pharmaceutical-tas-205-phase-3-clinical-trial-nct04587908/

5. https://www.clinicaltrialsarena.com/news/taiho-dmd-therapy-misses-mark-phase-iii/