PXT3003: Lessons for therapeutic development in Charcot-Marie-Tooth disease type 1A and related neuropathies

Most drug development stories end predictably: promising compounds either succeed or fail. Occasionally, however, a therapy repeatedly returns from apparent extinction. PXT3003 for Charcot-Marie-Tooth disease type 1A (CMT1A) represents one such example. More than a decade after early promise, the program has survived formulation instability, interrupted clinical development, regulatory uncertainty, and controversy surrounding efficacy before re-emerging with renewed evidence of clinical benefit. Yet, as with many therapeutic development programs, interpretation of the available evidence is influenced by the extent to which findings are publicly accessible. In a recent issue of iScience, a phase 3 clinical trial evaluated PXT3003, a combination of baclofen, naltrexone, and D-sorbitol, versus placebo over 15 months in participants aged 16-65 years with mild-to-moderate CMT1A across 25 sites in China. PXT3003 is not simply the story of one drug; it highlights the scientific, methodological, operational, and reporting challenges of developing disease-modifying therapies for slowly progressive inherited neuropathies.