Talarozole (formerly R115866, planned trade name Rambazole) was an investigational drug for the treatment of acne, psoriasis and other keratinization disorders. Development for that purpose has been discontinued. However, its effect in increasing retinoic acid is now being investigated in hand and knee osteoarthritis.
It has 750-fold higher potency than the earlier drug liarozole as well as greater selectivity, with more than 300-fold selectivity for inhibition of CYP26A1 over other steroid-metabolizing enzymes like CYP17A1 (17α-hydroxylase/17,20-lyase) and aromatase (CYP19A1).
↑Zhu L, Kamalathevan P, Koneva LA, Zarebska JM, Chanalaris A, Ismail H, etal. (December 2022). "Variants in ALDH1A2 reveal an anti-inflammatory role for retinoic acid and a new class of disease-modifying drugs in osteoarthritis". Science Translational Medicine. 14 (676) eabm4054. doi:10.1126/scitranslmed.abm4054. hdl:10044/1/101589. PMID36542696.
↑Giltaire S, Herphelin F, Frankart A, Hérin M, Stoppie P, Poumay Y (March 2009). "The CYP26 inhibitor R115866 potentiates the effects of all-trans retinoic acid on cultured human epidermal keratinocytes". The British Journal of Dermatology. 160 (3): 505–513. doi:10.1111/j.1365-2133.2008.08960.x. PMID19120344. S2CID205258196.