4D Molecular Therapeutics announced an update on their rare disease ophthalmology product candidate portfolio including Phase 1 dose escalation clinical trial safety and tolerability data with 4D-110 for choroideremia and 4D-125 for X-linked retinitis pigmentosa (XLRP) (n=12 patients total), and that the company received a notice of termination of the Collaboration and License Agreement by 4D-110 licensee Roche resulting in full rights to 4D-110 reverting to 4DMT. Initial Phase 1 Dose Escalation Safety and Tolerability Data Summary: 4D-110 for choroideremia and 4D-125 for X-linked retinitis pigmentosa Clinical trial designs and enrollment Both clinical trials employed standard 3+3 dose-escalation designed to assess the safety, tolerability and biologic activity of a single intravitreal injection of either 4D-110 or 4D-125 at two dose levels (3E11 or 1E12 vg/eye). A total of twelve patients were enrolled across dose escalation cohorts, including six who received 4D-110 (three at each dose level) and six who received 4D-125 (three at each dose level). Patients received a standard immunosuppression regimen with taper; adjustments were determined by investigators. The results described are based on data cut-offs as of April 12, 2021 for 4D-110 and April 27, 2021 for 4D-125.