A Phase 1b/2a, Open-Label, Dose-Exploration Basket Study to Investigate the Safety and Tolerability of Subretinally Injected OPGx-BEST1 Administered in Patients With Either Autosomal-Dominant BEST1 Disease (Best Vitelliform Macular Dystrophy [BVMD]) or Autosomal-Recessive Bestrophinopathy (ARB)
The goal of this clinical trial is to learn if drug OPGx-BEST1 works to treat BVMD and ARB Bestrophinopathy. It will also learn about the safety of drug OPGx-BEST1. The main questions it aims to answer are: Evaluate the safety and tolerability of drug OPGx-BEST1 in one eye (the treatment eye), for 5 years post-injection, in participants with BVMD or ARB. A second question it aims to answer is identification of the most appropriate dose strength of OPGx-BEST1 for clinical development. Evaluate the efficacy of single injection of OPGx-BEST1 in one eye for 5 years post-injection. What medical problems do participants have when taking drug OPGx-BEST1?
∙ Individuals who meet all the following criteria will be eligible to participate in the study:
• Provide informed consent to study assessments.
• Able and willing to comply with all study assessments for the duration of the study.
• ≥18 years old.
• ETDRS BCVA measured with standard testing distances:
‣ For the sentinel participant in each cohort, ≤20 letters (Snellen equivalent of 20/200 \[1.30 logMAR\] or worse)
⁃ For subsequent participants in the same cohort, 65 to 20 letters inclusive (Snellen equivalent of 20/50 \[0.40 logMAR\] to 20/200 \[1.30 logMAR\]).
• Genetic confirmation on chromosome 11q12-q13.1 of BVMD or ARB with a BEST1 genetic test or IRD panel test including a BEST1 variant test, by a Clinical Laboratory Improvement Amendments (CLIA) or European certified laboratory. If available test result is more than 15 years old, confirmation testing will be performed at Visit 1, with results needed by Visit 3.
• Confirmation of one disease-causing (pathogenic or likely pathogenic, autosomal-dominant) variant in the BEST1 gene for BVMD, as listed in the IB, or two variants for ARB per American College of Medical Genetics and Genomics/Association for Molecular Pathology (ACMG/AMP) variant interpretation.
• BVMD: Clinical phenotype and diagnosis consistent with advanced BVMD with active subretinal fluid or vitelliform material.
• ARB: Clinical phenotype and diagnosis consistent with ARB.