Poor aqueous drug solubility, and the resulting low bioavailability and potential lack of therapeutic effect, is a major challenge in oral drug delivery. One strategy to increase solubility and dissolution rate is conversion of the crystalline drug into its amorphous form. However, the amorphous forms are thermodynamically unstable and require stabilization to avoid recrystallization during storage or after in vivo administration. The drug is therefore commonly formulated as an amorphous solid dispersion (ASD) in which it is molecularly dispersed in a polymeric network. The polymer in the ASD stabilizes the drug in the solid state and thereby inhibits recrystallization during storage. Further, it may prevent (or delay) drug precipitation upon dissolution and improve solubility. This results in fast dissolution where the subsequent maintenance of supersaturated drug concentrations in vivo can drive absorption from the gastrointestinal tract. Oral dosage forms comprising ASDs have been successfully marketed, e.g. Venclexta, which is used to treat diseases such as chronic lymphocytic leukemia, and acute myeloid leukemia, and contains venetoclax as the active pharmaceutical ingredient and polyvinyl alcohol as the enabling excipient.