US FDA approves Mirati's lung cancer drug

The US Food and Drug Administration approved Mirati Therapeutics Inc's lung cancer drug adagrasib, the company said on Monday, sending its shares up more than 8% in extended trading.

Mirati's drug has been approved for treating adult patients with advanced lung cancer as determined by an FDA-approved test, who have received at least one prior systemic therapy.

Adagrasib, an oral drug, is designed to target a mutated form of a gene known as KRAS that occurs in about 13% of non-small cell lung cancers (NSCLC), the most common form of the disease, and less frequently in some other solid tumors.

Mirati said the drug will be sold under the brand name Krazati at a price of $19,750 for a 200 milligram tablet/180 count bottle.

Another KRAS inhibitor, Amgen Inc's Lumakras, is already available to treat patients suffering from advanced lung cancer as a second-line therapy, after an initial therapy fails or stops working.

Third-quarter sales of Lumakras, which was approved last year, totaled $75 million.

Mirati Chief Executive David Meek said in a recent interview that the drug is a compelling choice. "I think physicians and patients are going to appreciate having an effective option," he told Reuters, noting that 43% of second-line trial patients responded to adagrasib. Shares of Mirati have fallen about 55% since early this month, after the company's presentation of early data from studies of adagrasib in combination with Merck & Co's immunotherapy Keytruda as an initial treatment for metastatic NSCLC. The results showed that the combination helped about half of trial participants. But Mirati said it would first move to a trial only in patients with lower levels of the protein targeted by Keytruda, with a high bar of proving superiority over standard of care. Wall Street analysts, initially encouraged by the efficacy and safety findings, questioned Mirati's strategy for future combination studies. "We see a long and challenging path to Phase 3 data ... and possibility for an acquisition is likely off the table for now," BMO Capital Markets analyst Evan Seigerman said in a research note before the approval.