Impurity rejection in the crystallization of ABT-510 as a method to establish starting material specifications.

Understanding impurity rejection in a drug substance crystallization process is valuable for establishing purity specifications for the starting materials used in the process. Impurity rejection has been determined for all known ABT-510 impurities and for many of the reasonable & conceivable impurities. Based on this study, a very high purity specification (e.g., > 99.7%) can be set for ABT-510 with a high level of confidence.