First-in-Human Phase I/IB Dose-Finding Study of Adagrasib (MRTX849) in Patients With Advanced KRASG12C Solid Tumors (KRYSTAL-1)

• Published in: Journal of clinical oncology Vol. 40; no. 23; pp. 2530 - 2538
• Main Authors: Ou, Sai-Hong Ignatius, Jänne, Pasi A., Leal, Ticiana A., Rybkin, Igor I., Sabari, Joshua K., Barve, Minal A., Bazhenova, Lyudmila, Johnson, Melissa L., Velastegui, Karen L., Cilliers, Cornelius, Christensen, James G., Yan, Xiaohong, Chao, Richard C., Papadopoulos, Kyriakos P.
• Format: Journal Article
• Language: English
• Published: Wolters Kluwer Health 10.08.2022
• Subjects: RAPID COMMUNICATION
• ISSN: 0732-183X; 1527-7755; 1527-7755
• DOI: 10.1200/JCO.21.02752

PURPOSEAdagrasib (MRTX849) is an oral, highly selective, small-molecule, covalent inhibitor of KRASG12C. We report results from a phase I/IB study of adagrasib in non-small-cell lung cancer, colorectal cancer, and other solid tumors harboring the KRASG12C mutation.MATERIALS AND METHODSPatients with advanced KRASG12C-mutant solid tumors were treated with adagrasib 150 mg orally once daily, 300 mg once daily, 600 mg once daily, 1,200 mg once daily, or 600 mg orally twice a day using an accelerated titration design, which transitioned to a modified toxicity probability interval design when a predefined degree of toxicity was observed or target adagrasib exposure was achieved. Safety, pharmacokinetics, and clinical activity were evaluated.RESULTSTwenty-five patients were enrolled and received at least one dose of adagrasib. The recommended phase II dose (RP2D) was 600 mg twice a day on the basis of safety, tolerability, and observed pharmacokinetics properties. No maximum tolerated dose was formally defined. After a median follow-up of 19.6 months, eight of 15 patients (53.3%; 95% CI, 26.6 to 78.7) with RECIST-evaluable KRASG12C-mutant non-small-cell lung cancer treated at 600 mg twice a day achieved a confirmed partial response. The median duration of response was 16.4 months (95% CI, 3.1 to not estimable). The median progression-free survival was 11.1 months (95% CI, 2.6 to not estimable). One of two patients with KRASG12C-mutant colorectal cancer treated at 600 mg twice a day achieved a partial response (duration of response, 4.2 months). At the RP2D, the most common treatment-related adverse events (any grade) were nausea (80.0%), diarrhea (70.0%), vomiting (50.0%), and fatigue (45.0%). The most common grade 3-4 treatment-related adverse event was fatigue (15.0%).CONCLUSIONAdagrasib 600 mg twice a day was well tolerated and exhibited antitumor activity in patients with advanced solid tumors harboring the KRASG12C mutation.