=Mirati Therapeutics (MRTX): cancer trial results

• presented results from a phase 2 trial in which its cancer drug sitravatinib was combined with Bristol-Myers Squibb Co.'s cancer drug Opdivo
• The company also said that 18 patients had tumor reductions of more than 30%, and an early estimate of median duration response was more than nine months. Mirati plans a phase 3 randomized clinical trial comparing a combination of the two cancer drugs with the chemotherapy docetaxel. Bristol-Myers' Opdivo is a checkpoint inhibitor that has already been approved in non-small cell lung cancer. As part of a major trend over the last several years, drugmakers have been testing immuno-oncology drugs like sitravatinib in combination with other cancer drugs, hoping that they might be more effective together.

Mirati Therapeutics announces completed stage 1 safety and efficacy data from the ongoing Phase 1b clinical trial of single agent sitravatinib in patients with certain classes of oncogenic mutations 

The presentation provided an update from the pre-planned expansion cohort of the Phase 1b clinical trial of single agent sitravatinib in patients with CBL inactivating mutations. Eight patients were evaluable as of the data cut-off on August 27, 2018.

• In the subset of evaluable NSCLC patients, 1/2 confirmed partial responses were observed with 2/2 patients experiencing tumor regression.
• In the subset of evaluable melanoma patients, 1/2 confirmed partial responses in evaluable patients were observed with 1/2 patients experiencing tumor regression.
• In the subset of evaluable patients with other solid tumors, 2/4 had stable disease with 2/4 experiencing tumor regression.

CBL mutations are present in 1.5% of NSCLC, 3.5% of melanoma, and 2% of cancers of unknown origin.

Mirati Therapeutics presents updated positive clinical data from Sitravatinib immuno-oncology combination trial at ESMO 2018 Congress And announces FDA guidance for registration trial 

• Updated analysis from ongoing Phase 2 trial of sitravatinib in combination with nivolumab demonstrated significant clinical activity in patients with checkpoint refractory non-small cell lung cancer. - 16 partial or complete responses observed in first 56 evaluable patients.
• The Company also provided an update on the regulatory pathway for sitravatinib in checkpoint refractory NSCLC patients following a successful end of phase 2 meeting with the FDA.
• Based on guidance received from the FDA, Mirati plans to initiate a Phase 3 randomized clinical trial in second line patients comparing the combination of sitravatinib plus a checkpoint inhibitor to docetaxel in patients whose tumors have progressed on prior checkpoint inhibitor therapy.