The drug, larotrectinib, will be sold under the brand name Vitrakvi in partnership with Bayer AG.
The mutation, known as TRK fusion, occurs in no more than 3,000 Americans each year, or less than 1 percent of patients with solid tumor cancers, according to Bayer.
Vitrakvi, which will be Loxo's first commercial medicine, was approved for adults and pediatric patients who have advanced solid tumor cancers with the gene mutation that has progressed after other treatments, the FDA said.
In a 122-patient clinical trial, larotrectinib significantly reduced tumors in 81 percent of those with 24 different types of cancer, including lung, pancreatic, breast, thyroid, colon and soft tissue sarcomas. Researchers also reported an extremely mild side effect profile for the medicine.
"Today’s approval marks another step in an important shift toward treating cancers based on their tumor genetics rather than their site of origin in the body,” FDA Commissioner Scott Gottlieb said in a statement.
Merck & Co's Keytruda last year became the first cancer drug to win approval for a so-called tumor-agnostic use, although that remains a small market for the big-selling drug.
Currently, most cancer patients are not routinely tested for tumor mutations, making it difficult to find those who will benefit from the drug, although Bayer is talking with payers about expanding testing, Kevin O'Leary, vice president of pricing and contracting at Bayer, said in a phone interview.
Oppenheimer has forecast annual larotrectinib sales of more than $1 billion by 2024.
Loxo is also developing a drug, LOXO-292, that targets another rare gene fusion mutation known as RET, seen in thyroid, lung and other cancers. And Loxo and Bayer have a follow-up TRK drug in development known as LOXO-195.
Similar drugs being developed by Roche and others are expected to fuel increased demand for advanced genetic testing of tumors in order to identify the patients likely to benefit from the treatments.
The U.S. government earlier this year said the Medicare program for Americans aged 65 and older will cover so-called next generation sequencing, which looks for hundreds of mutations across all solid tumors, for advanced cancer patients. (Reporting By Deena Beasley Editing by Bill Berkrot)
(This story has not been edited by Devdiscourse staff and is auto-generated from a syndicated feed.)