Astellas Gene Therapies licensed ASP2957 (MyoAAV3.8‑MHCK7‑hMTM1), a MyoAAV capsid‑based gene therapy developed by Kate Therapeutics, and launched the Phase I/II VALOR trial in X‑linked myotubular myopathy. The therapy uses an engineered MyoAAV capsid to improve muscle cell uptake and aims to deliver therapeutic MTM1 at much lower viral doses than prior AAV approaches, addressing safety concerns tied to high‑dose AAV exposure. Astellas emphasized the capsid as the key differentiator from earlier, troubled programs and highlighted integrin‑targeted uptake that could lower systemic AAV dosing. The VALOR study (NCT07052929) will test safety and activity in XLMTM patients as the company seeks a safer gene‑replacement path for the disease.