Precision Medicine: FDA Approve ‘Wonder Drug’ That Treats Cancers Based On DNA And Not The Tumour

The Food and Drug Administration on Monday (26 November) announced that it has granted an “accelerated approval” for a drug that will treat a wide range of cancers based on a shared mutation, rather than the tumours’ locations.

The FDA said that the approval of Vitrakvi, or Larotrectinib, reflects a "new paradigm," as the drug targets a key genetic driver of cancer rather than a specific tumour type.

The FDA said the efficacy of the drug was studied in three clinical trials involving 55 children and adults. The patients had a 75 per cent overall response rate across different types of solid tumours, with almost all the responses lasting six months and 39 per cent lasting a year or more.

Larotrectinib was developed by Connecticut-based Loxo Oncology and has been tested at various sites around the United States (US) for several years. In a departure from the usual practice, it has been simultaneously approved to treat both children and adults whose cancer expresses a specific genetic change that occurs in an estimated 2,500 people each year. It has the potential to wipe out stubborn cancers with few to zero negative side effects, making it a unique entrant into the cancer treatment world.

According to a report in The Washington Post, the drug approved is for patients with advanced solid tumours containing what’s called an NTRK gene fusion, a hybrid of two genes that can promote uncontrolled cell growth.

Cancers of the thyroid, lung and head and neck, among others, can be caused by the defect. The drug is for patients whose cancer has spread or who would experience severe complications by undergoing surgery and have no satisfactory alternatives.

The breakthrough drug comes at a high price - $32,800 for a 30-day supply of capsules for adults and liquid formulation for children that will start at $11,000 per month.

Loxo, however, now faces a huge challenge. Only an estimated 2,000 to 3,000 people a year in the US develop NTRK-related cancers. The only way to find the mutation is through much broader genetic tumour testing which is not a common practice as of yet.