molecules of the month

Retinol-binding protein 4 (RBP4) is the sole carrier for retinol (vitamin A). It may also play a role in diabetes and reduction of RBP4 may be beneficial for the ocular disease AMD. Belite Bio had a Ph. III trial ongoing for an oral RBP4 antagonist (LBS-008, tinlarebant) in Stargardt Disease and intends to start a Ph. III trial for AMD in 2022. Stargazer Therapeutics completed a Ph. II study for STG-001 in April. Retinol-bound RBP4 complexes with transthyretin (TTR) to avoid renal clearance, but after release of retinol, apo-RBP4 is excreted by the kidney. Most apo-RBP4 is reabsorbed and degraded. “compound 43b” is proposed to disrupt the RBP4-TTR protein-protein interaction (PPI), reducing blood RBP4 levels in mice at orally doses…