Syndax secures FDA OK for new kind of leukemia drug

Dive Brief:

  • Massachusetts-based Syndax Pharmaceuticals won Food and Drug Administration approval Friday for a new kind of drug to treat an aggressive form of leukemia in adults and some children.
  • The oral drug, which Syndax will sell as Revuforj, is the first of its type, a class of compounds known as menin inhibitors. It’s cleared for patients one year or older who have relapsed or refractory acute leukemia that harbors a specific mutation: translocations in the lysine methyltransferase 2A, or KMT2A, gene.
  • People with this type of leukemia are more likely to relapse and have a median overall survival of less than one year. Syndax plans to launch two doses of the drug, which it priced at about $475,000 per year before rebates or discounts, later in November. A lower dose for patients who weigh less will be available next year.

Dive Insight:

The FDA’s decision comes more than a month before the agency’s Dec. 26 deadline.

The regulator cleared Revuforj based its analysis of data from 104 patients given Syndax’s drug in early-stage trials. Just over one-fifth of those patients experienced a complete remission, which lasted a median of about six months. Twenty-three percent of participants went on to receive a stem cell transplant after Revuforj.

The drug’s labeling contains a black box warning for differentiation syndrome, which occurred in 29% of all 135 patients treated with Revuforj. Sometimes known as retinoic acid syndrome, differentiation syndrome is a potentially fatal reaction to cancer therapies in people with acute leukemia.

Jefferies analyst Kelly Shi, writing in a note to clients, said such a warning was expected for Revuforj and noted that the labeling is “similar to almost all other AML-targeted therapies.”

Syndax will first make 110 milligram and 160 milligram dose forms of Revuforj available, before readying a 25 milligram tablet.

The company estimates about 2,000 people in the U.S. have acute leukemia with a KMT2A translocation. According to Shi, the company anticipates that “most patients will have commercial insurance coverage given [patients] younger age.”

Shi predicts peak annual sales of Revuforj to eventually reach about $200 million for the KMT2A indication alone.