Results from molecular analysis for therapy choice (MATCH) arm I: Taselisib for PIK3CA-mutated tumors.

101Background: MATCH is a trial that assigns patients (pts) with solid tumors, lymphomas, or multiple myeloma to specific targeted therapies based on genetic alterations identified in fresh tumor biopsies. Arm I evaluated the PI3-kinase inhibitor taselisib in pts with activating mutations in PIK3CA, the catalytic subunit of PI3-kinase. Methods: Pts with KRAS mutations or PTEN mutation or loss were excluded, as were pts with breast or squamous lung cancer. Pts received taselisib 4 mg po daily on 28 d cycles until progression or intolerable toxicity. Staging was every 2 cycles. The primary endpoint was objective response (OR); secondary endpoints were PFS, 6-month PFS, and predictive biomarkers. Results: 65 pts (enrolled 3/2016-4/2017) received ≥1 dose of study therapy; 45 tumor types were represented; 38% of pts had > 3 prior lines of therapy. There were no ORs, but prolonged stable disease was observed (estimated PFS6 rate 27%, 90% CI 19%-39%), and 2 pts remain on study > 1 yr. The most common toxicities ...