Addition of Rigosertib Fails to Improve Survival in Pancreatic Cancer

Compared with gemcitabine (GEM) monotherapy, rigosertib (RIG) and gemcitabine (GEM) combination did not improve survival in patients with treatment-naïve metastatic pancreatic adenocarcinoma, according to a recent study first published online this week in the journal Annals of Oncology.

The phase 2/3, two-arm international study had a total of 160 patients who were randomly assigned to RIG plus GEM or GEM alone. 

Results showed that there was no significant difference between the treatment arms for median overall survival where median overall survival was 6.1 months for RIG plus GEM and 6.4 months (HR= 1.24; 95% CI: 0.85, 1.81) for GEM.

The median progression-free survival was similar between arms as well, with 3.4 months (HR=0.96; 95% CI: 0.68, 1.36) in both arms. The partial response rate was slightly higher for RIG plus GEM (19%) compared with GEM alone (13%).

The most common grade 3 or higher adverse events with RIG plus GEM versus GEM alone, respectively, were neutropenia (8% vs. 6%), hyponatremia (17% vs. 4%), and anemia (8% vs. 4%).

The study suggests that RIG plus GEM is no better than GEM alone to improve survival in treatment-naïve metastatic pancreatic cancer. Moreover, the similar safety profile for rigosertib was seen in the previous trials.

Reference

1. O’Neil BH, Scott AJ, Ma WW, et al. A phase II/III randomized study to compare the efficacy and safety of rigosertib plus gemcitabine versus gemcitabine alone in patients with previously untreated metastatic pancreatic cancer. Ann Oncol. 2015. [Epub ahead of print]. doi: 10.1093/annonc/mdv264.