Veliparib: Analytical Tools and Process Design Strategies for the Control of Mutagenic Impurities and Other Drug Substance Critical Quality Attributes

(R)-Veliparib (ABT-888) is a poly(ADP-ribose)polymerase (PARP) inhibitor that is being investigated for the treatment of a broad spectrum of oncology indications, including BRCA1/2-mutated breast cancer and other solid tumors. The (R)-veliparib process consists of three stages utilizing two proposed regulatory starting materials, (R)-Boc-2-methylproline and 2,3-diaminobenzamide dihydrochloride, with two isolated intermediates. The drug substance control strategy, which was established based on a combination of analytical tools and uniquely designed manufacturing process and unit operations, provides robust controls for mutagenic and other impurities and ensures that (R)-veliparib drug substance consistently meets all critical quality attributes (CQAs) and acceptance criteria. The purpose of this article is to provide details of how the (R)-veliparib control strategy for the selected CQAs was cross-functionally developed using analytical measurement tools and specially designed unit operations.