Bietti Crystalline Dystrophy Clinical Trials 2026 — Find Recruiting Studies

About Bietti Crystalline Dystrophy

Bietti Crystalline Dystrophy is a rare progressive retinal degeneration caused by mutations in CYP4V2, a gene encoding a cytochrome P450 enzyme involved in fatty acid metabolism, leading to the pathological accumulation of lipid crystalline deposits in the cornea, retina, and circulating lymphocytes. The disease is notably more prevalent in individuals of East Asian descent and is characterised by glistening yellow-white crystals scattered across the posterior pole of the retina, progressive chorioretinal atrophy, and eventual severe visual impairment. Disease progression is typically slow but relentless, with most patients reaching legal blindness by the fifth or sixth decade.

Common Clinical Features

Glistening crystalline deposits in the posterior retina visible on fundus examination Progressive chorioretinal atrophy beginning in the posterior pole Night blindness and dark adaptation difficulties Visual field constriction beginning in the periphery Decreased central visual acuity in advanced stages Corneal limbal crystals detectable on slit-lamp examination Reduced ERG responses (both rod and cone affected) Legal blindness in the fifth to sixth decade

Clinical Trial Eligibility Tips

What to know before applying to Bietti Crystalline Dystrophy trials.

Molecular confirmation of biallelic CYP4V2 pathogenic variants is necessary; the high prevalence of a specific splicing variant in East Asian patients means targeted testing is often efficient.

Fundus autofluorescence and OCT are used to measure areas of surviving RPE and photoreceptors, which serve as eligibility and outcome measures in emerging trials.

Given the slow progression, early enrolment in natural history studies can establish a baseline that strengthens eligibility for future interventional trials.