BCVA may not be sensitive enough for assessing gene therapies in choroideremia

Best-corrected visual acuity (BCVA) is not an ideal outcome measure for clinical trials in choroideremia, especially in early and mid-stage disease, according to a new study that shows BCVA is less sensitive to disease progression and therapeutic effects compared to other functional measures like microperimetry.

Clinical trials should prioritize more sensitive measures, such as microperimetry, to better assess the impact of treatments, particularly in the earlier stages of the disease.

The research used retrospective dominance analysis to evaluate data from untreated eyes in a longitudinal clinical trial. Correlating functional tests with disease progression, as measured by the area of retinal survival on blue fundus autofluorescence imaging, the study ranked the importance of various outcome measures.

Microperimetry emerged as the most sensitive and important functional test, followed by factors such as time since baseline, Pelli-Robson contrast sensitivity, and low luminance visual acuity. In contrast, BCVA under standard lighting was ranked the least sensitive to disease progression and therapeutic effects.

Reference
Josan AS, Taylor LJ, Xue K, et al. Ranked Importance of Visual Function Outcome Measures in Choroideremia Clinical Trials. Invest Ophthalmol Vis Sci. 2024;65(13):58. doi: 10.1167/iovs.65.13.58. PMID: 39601638.