1Q26 Update. Upcoming R&D Event June 16th Should Lay Out the De-Risked Pipeline. September BEST1 Cohort 1 Readout Likely Next Big Catalyst.

Research evidence excerpt

1Q26 Update. Upcoming R&D Event June 16th Should Lay Out the De-Risked Pipeline. September BEST1 Cohort 1 Readout Likely Next Big Catalyst.

■ ...Q4 2026), OPGx-MERTK (entering clinic end of 2026), and OPGx-RHO (entering clinic 2027). These are not speculative

placeholder programs, but they are assets with validated biology and clear clinical entry timelines that simply needed the

funding catalyst. The most recent decision to advance RDH12, a program partially funded by the RDH12 Alliance targeting a

pediatric IRD affecting ~2,500 U.S. patients, is emblematic of exactly that dynamic. The capital is now in place and execution

is the story from here.

■ BEST1 next steps. On BEST1, more data from the full 5-person cohort is expected mid this year. The initial BEST1 correction

patient surpassed our expectations, with a highly visually impaired "sentinel" patient demonstrating both structural and

functional improvements. The Phase 1/2 BIRD-1 trial, enrolling both dominant and recessive BEST disease patients across

multiple U.S. sites, has treated two participants to date with data from the first recessive patient released recently. The 12-BIOTECHNOLOGY

letter absolute gain in Best Corrected Visual Acuity (BCVA) in the treated eye (8 letters placebo corrected), which is well into

the range considered meaningful for wAMD treatment, was accompanied by a 23% reduction in central subfield thickness

(CST) and resolution of intraretinal fluid as early as one month in regions with less atrophy. The next patients are expected

to be similarly impressive and the cautious expectations for the sentinel patient were based on the degree of impairmentEQUITY anticipated for this patient. These next patients are likely to be the dominant form of BEST1 disease, but the preclinical