(Reuters) -The U.S. Food and Drug Administration on Monday approved Mirati Therapeutics (NASDAQ:) Inc’s lung cancer drug adagrasib, according to the health regulator’s website, sending the company’s shares up more than 8% in extended trading.

Mirati was seeking approval for the drug for treating patients with advanced lung cancer who have stopped responding to other therapies.

Adagrasib, the 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 did not immediately respond to a Reuters request for comment over the drug’s pricing and availability.

Another KRAS inhibitor, Amgen Inc (NASDAQ:)’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.

Earlier this month, Mirati presented early data from studies of adagrasib in combination with Merck & Co’s immunotherapy Keytruda as an initial treatment for metastatic NSCLC.

The results showed the combination helped about half of trial participants. However, Mirati said it would first conduct a pivotal trial only in patients with lower levels of the protein targeted by Keytruda, with a high bar of proving superiority over standard of care.