Slowing or Delaying Vision Loss in Retinitis Pigmentosa (USH2A gene mutation subtype) → Pharmacological Treatments Can Slow Degeneration → Contribution
Does Vitamin A slow RP progression?
Method
Literature review of historical clinical recommendations and meta-analyses on Vitamin A palmitate for RP.
Data / Sources
Berson et al. (1993) landmark trial, subsequent follow-up studies, FDA/NEI guidance documents.
Result
Mixed evidence. The original Berson trial suggested ~20% slower decline in ERG amplitude with 15,000 IU/day Vitamin A palmitate. However, subsequent studies have questioned the magnitude of benefit and raised concerns about hepatotoxicity and potential harm in certain genotypes.
Insight
Potential benefit is uncertain and may depend on dosage and patient profile. Risk-benefit balance is unclear, especially for USH2A-specific RP.
Suggested Next Step
Investigate whether USH2A-specific studies exist for Vitamin A. Review current ophthalmologist recommendations.