Incyte's faithful Jakafi—and its sales force—are ready to roll with new indication

Incyte's Jakafi has become the first FDA-approved drug for patients with acute graft-versus-host disease who do not respond to steroids.(Incyte)

Incyte's bone marrow drug Jakafi has been pitching in blockbuster-level sales, and now it has a new approval that could give it another boost.

The FDA on Friday greenlighted Jakafi to treat acute graft-versus-host disease (GVHD) in patients who've failed steroid treatment. That makes Jakafi the first FDA-approved drug for the condition, a potentially serious complication of a bone marrow or stem cell transplant, Incyte CEO Hervé Hoppenot said in a statement.

And Incyte is ready to roll with the new nod. “Our field force has already been sized and structured to support the launch,” Incyte’s U.S. general manager Barry Flannelly said on the company’s first-quarter earnings call in April.

GVHD makes three indications for Jakafi, which is also approved to treat the bone marrow disorders polycythemia vera and myelofibrosis. The approval came three months later than expected after the FDA extended its review to consider newly submitted data.

Steroid-resistant acute GVHD can be fatal, with a one-year mortality rate of about 70%, Incyte said. “Every year in the United States, about half of the people who develop acute GVHD do not respond adequately to steroids, making it an extremely challenging disease to treat,” Madan Jagasia, lead investigator of a phase 3 trial in the indication, said in a statement.

In the open-label, single-arm study dubbed Reach1, Jakafi in tandem with corticosteroids elicited an overall response rate of 57% after 28 days among 49 patients who didn't respond to steroids alone. Novartis, which holds ex-U.S. rights to the drug, is conducting Reach2 and Reach3 studies that pit Jakafi against best available therapies in acute GVHD and chronic GVHD, respectively. Readouts from those two larger phase 3 trials are expected later this year.

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The JAK class was hit with a scare early this year when Pfizer’s rheumatoid arthritis med Xeljanz ran into cardiovascular risks with a higher dose in postmarketing studies. Eli Lilly’s Olumiant, developed by Incyte, was only approved in the lower dose Lilly had proposed and was slapped with a black box warning about the risk of blood clots.

But that doesn't seem to have affected Jakafi. The drug hauled in $375.6 million for Incyte in the first quarter, up 20% year over year, Flannelly said on the call. The company expects full-year sales to hit in the $1.58 billion to $1.65 billion range and sees $2.5 billion to $3 billion in annual sales by 2027.

With about 10 years of patent life left, Incyte is also working on extended-release formulations and testing Jakafi in multiple combinations.

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But Incyte has other plans in GVHD, too. It's developing itacitinib in previously untreated patients, with phase 3 results in acute GVHD due by year's end. Another recently launched pivotal trial is testing the candidate for chronic GVHD. Because itacitinib is a JAK1-specific inhibitor, it could be a better option than JAK1/2 dual inhibitor Jakafi.

“We really think that we could continue to develop [Jakafi] or people will use [Jakafi] in that setting, but ultimately itacitinib should be the drug of choice in steroid-refractory and acute GVHD,” Incyte Chief Medical Officer Steven Stein said on the first-quarter call.