What's Going On With Mirati (MRTX) Shares Today

Mirati Therapeutics Inc MRTX announced preliminary results from the KRYSTAL-7 Phase 2 trial and KRYSTAL-1 Phase 1b cohort of adagrasib combined with Merck & Co Inc's MRK Keytruda (pembrolizumab) in previously untreated metastatic lung cancer patients, harboring a KRASG12C mutation.
Early data shows that a combination treatment demonstrated promising preliminary clinical activity across all PD-L1 subgroups with an objective response rate (ORR) of 49%, with a manageable safety profile.
Related: Mirati Therapeutics Garners Interest From Large Pharmas Ahead Of Much Awaited Data Next Month.
Wall Street analysts called the early results encouraging, Reuters reported, but shares of Mirati were down more than 8%. More trial details will be presented on Wednesday.
"We believe the data continue to support the regimen's differentiated positioning relative to standard of care and are far more favorable than that of Lumakras plus (immunotherapy)," a JP Morgan analyst said, referring to Amgen Inc's AMGN drug.
Out of seven phase-two trial patients given the adagrasib combination, four (57%) had tumor shrinkage and a disease control rate of 100%.
Price Action: MRTX shares traded 9.60% lower at $83.85 during pre-market trading on Tuesday.

Mirati Experimental Lung Cancer Drug Shows Favorable Tolerability, Promising Efficacy