- The European Medicines Agency on Thursday recommended against approving Mirati Therapeutics’ KRAS-targeting lung cancer drug, setting back the biotechnology company’s attempt to follow Amgen’s rival drug Lumakras to market there.
- In reaching its decision, the EMA’s human medicines committee cited a lack of comprehensive data on how well Mirati’s drug works, which fell short of meeting the regulator’s standard for recommending a conditional marketing authorization.
- Mirati plans to request a formal reexamination by the EMA, adding in a statement that it believes its drug, called Krazati, is differentiated enough from Amgen’s to merit a conditional approval. Under EMA rules, such clearances are limited to medicines with a positive risk-benefit balance that fulfill an “unmet medical need.”
The EMA’s recommendation breaks with the verdict reached by the Food and Drug Administration, which late last year granted an accelerated approval to Krazati. If upheld, it will hinder Mirati’s attempt to challenge Amgen in Europe as well as the U.S.
Both companies’ drugs target a gene called KRAS, which, when mutated, can drive the growth of certain tumors, particularly those in the lung, colon and pancreas. Mirati has been a step behind Amgen, but is pitching Krazati as offering different advantages, such as potential activity against metastases in the central nervous system.
According to Mirati, the EMA’s drugs committee agreed Krazati has a positive-risk benefit balance, but said the company’s application “does not fulfill certain requirements for a conditional marketing authorization.”
Mirati’s application included data from a Phase 2 portion of a study called KRYSTAL-1, which tested a 600 milligram dose in 116 patients with non-small cell lung cancer confirmed to have a certain type of KRAS mutation. Participants had previously been treated with platinum-based chemotherapy and immunotherapy.
Results showed treatment led to tumor responses in about 40% of participants, which lasted a median of around eight months.
While the benefit offered by both Krazati and Lumakras before it are viewed as modest, the drugs are an improvement over what would be expected with chemotherapy in patients whose KRAS-mutated lung cancer has already progressed after initial treatment.
The EMA’s decision does not affect Mirati’s ongoing studies, nor availability of Krazati via compassionate use programs in Europe, the company said. A Phase 3 trial, dubbed KRYSTAL-12, is testing Krazati against the chemo drug docetaxel, and results are expected in the first half of next year.
Shares in Mirati dropped by about 9% in Friday morning trading.
While the negative recommendation delays Mirati’s entry in Europe, Amgen’s January 2022 entry with its drug has not led to significant sales. Over the first three months of the year, Lumakras earned Amgen $26 million in all countries outside of the U.S.