{Reference Type}: Clinical Trial, Phase I {Title}: A First-in-Human Phase I Study to Evaluate the ERK1/2 Inhibitor GDC-0994 in Patients with Advanced Solid Tumors. {Author}: Varga A;Soria JC;Hollebecque A;LoRusso P;Bendell J;Huang SA;Wagle MC;Okrah K;Liu L;Murray E;Sanabria-Bohorquez SM;Tagen M;Dokainish H;Mueller L;Burris H; {Journal}: Clin Cancer Res {Volume}: 26 {Issue}: 6 {Year}: 03 2020 15 {Factor}: 13.801 {DOI}: 10.1158/1078-0432.CCR-19-2574 {Abstract}: ERK1/2 signaling can be dysregulated in cancer. GDC-0994 is an oral inhibitor of ERK1/2. A first-in-human, phase I dose escalation study of GDC-0994 was conducted in patients with locally advanced or metastatic solid tumors.
GDC-0994 was administered once daily on a 21-day on/7-day off schedule to evaluate safety, pharmacokinetics, and preliminary signs of efficacy. Patients with pancreatic adenocarcinoma and BRAF-mutant colorectal cancer were enrolled in the expansion stage.
Forty-seven patients were enrolled in six successive cohorts (50-800 mg). A single DLT of grade 3 rash occurred at 600 mg. The most common drug-related adverse events (AE) were diarrhea, rash, nausea, fatigue, and vomiting. Pharmacokinetic data showed dose-proportional increases in exposure, with a mean half-life of 23 hours, supportive of once daily dosing. In evaluable paired biopsies, MAPK pathway inhibition ranged from 19% to 51%. Partial metabolic responses by FDG-PET were observed in 11 of 20 patients across dose levels in multiple tumor types. Overall, 15 of 45 (33%) patients had a best overall response of stable disease and 2 patients with BRAF-mutant colorectal cancer had a confirmed partial response.
GDC-0994 had an acceptable safety profile and pharmacodynamic effects were observed by FDG-PET and in serial tumor biopsies. Single-agent activity was observed in 2 patients with BRAF-mutant colorectal cancer.