Shares of Onconova Therapeutics, Inc. [NASDAQ: ONTX] surged 16.53% as the company has shared the promising preliminary safety and efficacy data from a Phase 1/2a study of oral rigosertib plus the immune checkpoint inhibitor nivolumab in advanced KRAS mutated (KRAS+) non-small cell lung cancer (NSCLC).
The data was presented in a presentation at the 3rd Annual RAS Targeted Drug Development Summit. The data which is being shared by the company support the possible anti-cancer activity of rigosertib-nivolumab combination therapy in this indication and demonstrate that the doublet has been well endured.
Additionally, the data from the presentation disclosed that all registered patients (12/12) were not successful at least one line of previous treatment with a PD-1 checkpoint inhibitor. 75% of enrolled patients have not shown satisfactory results in at least two previous lines of treatment. The combination of rigosertib and nivolumab has been well endured and the maximum endured dose has not been achieved to date.
The data which the firm has presented demonstrate that the radiographic responses were witnessed across multiple KRAS variants, which possibly distinguishes rigosertib from other RAS pathway modulators that target specific KRAS mutations. These responses were seen at the primary tumor site as well as metastatic sites such as the pleura and bone. Overall the Phase 1/2a study has shown promising results.