Data from Pharmawand - Curated by Marshall Pearce - Date added 19 April 2017
OncoMed Pharmaceuticals, Inc. reported top-line results from the company's randomized 145-patient Phase II PINNACLE clinical trial of tarextumab (anti-Notch2/3, OMP-59R5) in combination with etoposide plus either cisplatin or carboplatin chemotherapy ("chemotherapy") in previously untreated patients with extensive-stage small cell lung cancer.
Results for the combination of tarextumab plus chemotherapy were undifferentiated from those of chemotherapy plus placebo, and therefore the trial did not meet its primary endpoint of progression-free survival or secondary endpoints of overall survival and biomarkers reflective of Notch pathway gene activation.
OncoMed also announced that it will discontinue enrollment in the Phase 1b clinical trial of brontictuzumab (anti-Notch1, OMP-52M51) in combination with trifluridine/tipiracil (Lonsurf) in third-line colorectal cancer patients. The combination of brontictuzumab plus chemotherapy was not tolerable in this patient population.
The median progression-free survival (mPFS) for tarextumab plus chemotherapy was 5.6 months versus 5.5 months for chemotherapy plus placebo (HR=0.969). The median overall survival (mOS) analysis did not show a benefit for tarextumab in combination with chemotherapy (mOS=9.3 months) compared to the chemotherapy plus placebo arm (10.3 months; HR=1.01). Five individual Notch biomarkers (Hes1, Hes6, Hey1, Hey2 and Notch3) failed to identify a definitive subset of patients with a treatment effect on either mPFS or mOS. Overall response rates were 68.5% and 70.8% in the tarextumab and placebo arms respectively. The combination of tarextumab plus chemotherapy was well tolerated. The safety profile appeared to be similar between the two groups except for diarrhea and thrombocytopenia, which were more prevalent in the tarextumab treatment arm, and constipation, which was more prevalent in the placebo arm.