Experimental solubility profiling of marketed CNS drugs, exploring solubility limit of CNS discovery candidate.

We determined the experimental solubility of CNS marketed drugs. Of the 98 drugs measured, greater than 90% had solubility >10 μM in pH 7.4 buffer. Only seven drugs had solubility <10 μM. Using these data, we established a solubility criterion to support CNS discovery. The implication of poor solubility with potential safety concerns and undesirable side effects are discussed.