Paxalisib (GDC-0084): A Brain-Penetrant PI3K/mTOR Inhibitor for CNS Malignancies

1. Introduction to Paxalisib (GDC-0084)

1.1. Overview and Chemical Identity

Paxalisib, an investigational small molecule drug, is also identified by its developmental code name GDC-0084 and synonym RG7666.[1] It is cataloged in DrugBank with the Accession Number DB15186.[1] The Chemical Abstracts Service (CAS) Number for Paxalisib is 1382979-44-3.[1]

The IUPAC name for Paxalisib is 5-(6,6-dimethyl-4-morpholin-4-yl-8,9-dihydropurino[8,9-c]\oxazin-2-yl)pyrimidin-2-amine.[1] An alternative chemical name is 5-(6,6-Dimethyl-4-morpholino-8,9-dihydro-6H-\oxazino[4,3-e]purin-2-yl)pyrimidin-2-amine.[3] Paxalisib has a molecular formula of C18H22N8O2, corresponding to an average molecular weight of 382.428 g/mol and a monoisotopic mass of 382.18657198 Da.[1]

The presence of multiple identifiers such as GDC-0084 and RG7666, alongside the formally adopted name Paxalisib (USAN/INN), reflects the typical progression of a drug through distinct research and development phases. GDC-0084 was likely Genentech's internal research designation during its early discovery and development. As a compound advances into more formal clinical development and towards potential commercialization, it receives an official non-proprietary name like Paxalisib, which is recognized globally by regulatory authorities and in scientific literature.[1] This nomenclature evolution is a standard practice in the pharmaceutical industry, marking the transition from an early-stage research compound to a more mature clinical candidate.

Table 1: Paxalisib - Key Drug Information