On a JAK roll, Incyte wins FDA green light to expand Jakafi in chronic graft-versus-host disease

Jakafi could reach $293 million sales from chronic graft-versus-host disease in 2022, Jefferies analyst Biren Amin projected in February. (Incyte)

Right on the heels of crossing the FDA finish line with topical ruxolitinib, Incyte has snagged another go-ahead for the original oral formulation, Jakafi.

Expanding on its 2019 FDA nod for acute graft-versus-host disease (GVHD), Jakafi is now allowed to treat chronic GVHD after patients fail on one or two lines of systemic therapy, Incyte said Wednesday.

Even before the approval, doctors have already been using off-label Jakafi for chronic GVHD. That's because the JAK inhibitor is included in the National Comprehensive Cancer Network guidelines, alongside more than a dozen other therapies.

Citing that existing use, SVB Leerink analyst Andrew Berens predicts the approval will have a “minimal” effect for Incyte. For her part, Cantor Fitzgerald analyst Alethia Young noted that an official approval will help drive future sales. About 14,000 chronic GVHD patients live in the U.S., with nearly half not responding to steroids, Young said.

Jakafi proved its mettle in the phase 3 Reach3 trial. Among patients with steroid-refractory chronic GVHD, Jakafi triggered a response in 49.7% of them. That compared with 25.6% for best available therapy.

Still, in an investor note earlier this year, Jefferies analyst Biren Amin said there’s “insufficient evidence to recommend one systemic agent” over another among the NCCN-recommended drugs. At that time, Amin predicted Jakafi could reach $293 million sales from chronic GVHD in 2022.

To reach that conclusion, the Jefferies team surveyed 25 U.S.-based hematology and transplantation specialists who treat an average of 24 chronic GVHD patients per year. Doctor feedback showed that calcineurin inhibitors lead the steroid-refractory space with 34% of market share, followed by Jakafi at 15%. In the third-to-fifth lines, Jakafi ranked either first or second in market share at each line of treatment.

Altogether, 92% of surveyed doctors said they will mostly use Jakafi for second- and third-line treatment of chronic GVHD, the analysts wrote.

RELATED: Kadmon eyes $15.5K price tag and August debut for new transplant rejection med Rezurock

Meanwhile, pharma giant Sanofi just bought an approved asset in the increasingly fragmented chronic GVHD market with its $1.9 billion purchase of Kadmon. Kadmon’s Rezurock earned an FDA nod in July for patients who’ve failed on two prior systemic therapies.

In Jefferies’ survey, 88% of doctors said they were willing to prescribe the drug as a third-line treatment or later. That means the ROCK inhibitor will likely be used after failure of Jakafi, Amin observed.

The FDA evaluated Jakafi’s latest application under Project Orbis, which allows for concurrent submission and review of oncology drugs among international regulators. In addition to GVHD, Jakafi is also approved for certain blood cancers.

Though a nice addition, Jakafi’s latest label expansion is of less importance to Incyte than the atopic dermatitis approval for its sister med Opzelura, or ruxolitinib cream.

RELATED: Incyte's Jakafi sister med clears FDA for atopic dermatitis, but safety warning a heavy cross to bear

While Jakafi dodged a bullet amid FDA’s increased scrutiny over JAK inhibitor safety, Opzelura suffered collateral damage with a class-wide boxed warning on its label. In her Thursday note, Young said the box warning will add skepticism and make uptake more challenging.  

Incyte has projected a peak sales of $1.5 billion for Opzelura, in line with Wall Street’s consensus 2030 estimates. But SVB Leerink’s Berens expects only $377 million in 2030 sales for Opzelura in atopic dermatitis or $560 million in total risk-adjusted sales.