SOLAR: Phase Ib Dose Expansion of Selumetinib (MEK Inhibitor) and OLAparib (PARP Inhibitor) Combination in Solid Tumors with RAS Pathway Alterations and in PARP Inhibitor-Resistant Ovarian Cancer (LBA 9)

Preclinical data from our team demonstrated that MEK inhibition induces synthetic lethality in combination with PARP inhibitors (PARPi) in tumors with RAS pathway alterations. In the phase Ib dose escalation, we identified the recommended phase II dose (RP2D) for the combination: olaparib 300 mg and selumetinib 75 mg orally twice daily. We sought to further explore the toxicity and efficacy of the combination in relevant cohorts.