Along with rifampicin and dapsone, the CFZ is used for the treatment of leprosy . CFZ has dark brown colour. According to Ra calculation, both POzi based hydrophobic blocks showed higher and equal compatibility for CFZ (Figure ), when compared to POx based polymers. The order of compatibility was found to be, i.e. pPrOzi ≈ pBuOzi > pPentOx > pBuOx. The maximum achievable formulation solubility of CFZ was 0.2 g/L by A-pBuOzi-A, A-pPentOx-A and A-pBuOx-A at 4, 4 and 6 g/L CFZ feed, respectively (Figure ). The in-house aqueous solubility determination was not possible, because CFZ was found completely insoluble in water (Table ). The A-pPrOzi-A triblock was found to be the worst solubilizer. Once again, the compatibility results are not consistent with the formulation profile.