NEW YORK – Exelixis has garnered an exclusive license to develop and commercialize Insilico Medicine's USP1 inhibitor ISM3091 as a treatment for various solid tumors including those harboring BRCA1/2 mutations.
On Tuesday, Exelixis said it will pay Insilico $80 million upfront in the third quarter for the exclusive rights to the agent, which "has emerged as a synthetic lethal target in the context of BRCA-mutated tumors," the companies said in a statement. Insilico, headquartered in Science Park, Hong Kong, is also eligible to receive future development, commercial, and sales-based milestone payments, as well as tiered royalties on net sales of ISM3091.
USP1 is involved in DNA damage repair through the removal of ubiquitin from proteins that stabilize the replication fork. ISM3091, which Insilico discovered using its Chemistry42 generative AI platform, is designed to inhibit USP1, which may prove lethal to tumor cells already deficient in their ability to repair DNA damage due to BRCA1/2 mutations. Based on preclinical data and tumor models, Exelixis and Insilico have confidence in ISM3091's unique profile among USP1 inhibitors, since it has shown activity not only against BRCA1/2-mutant cancers but also in homologous recombination DNA repair-proficient models, as a single agent and when paired with PARP inhibitors.
The US Food and Drug Administration earlier this year cleared Insilico's investigational new drug application, granting it permission to study ISM3091 in patients with solid tumors. In scooping up rights to the agent, Alameda, California-headquartered Exelixis said it intends to quickly begin enrolling a Phase I trial.