Kadmon's Rezurock scores surprise FDA nod in chronic graft-versus-host-disease

With a surprise FDA approval Friday afternoon, Kadmon Holdings is on its way to becoming a commercial drugmaker. 

The FDA cleared Kadmon’s Rezurock to treat chronic graft-versus-host disease, a serious complication of transplant procedures. Formerly known as belumodsil, the drug is a first-in-class ROCK2 inhibitor—and now Kadmon’s first approved drug. 

GVHD occurs when donor cells mount an immune response against a patient’s own tissues and organs. While doctors can try to use steroids to reduce the immune reaction, that doesn’t always work. 

The FDA based its Rezurock approval on data from an open-label trial called ROCKstar that enrolled 65 patients who had previously tried between two and five different treatments.

At median, study patients had cycled through three previous lines of therapy before trying Rezurock. After seven cycles of treatment, 75% of patients had responded. After a year's followup, 62% of those who responded still didn't need systemic therapy. 

RELATED: Kadmon's graft-versus-host disease med on track for 2020 filing 

The FDA approval, which applies to patients who've tried at least two different drug treatments, came six weeks ahead of the agency's decision deadline. Rezurock won’t be available until the end of August, Kadmon said. Cantor Fitzgerald analysts predict Rezurock can deliver $500 million in peak sales. 

Kadmon shares were trading up about 20% at 3 p.m. ET on Friday afternoon. 

RELATED: Kadmon drops detailed look at cGVHD data; analysts see 'underappreciated potential' 

Aside from chronic GVHD, Kadmon is testing the medicine in systemic sclerosis. The biotech also has an immuno-oncology candidate called KD033.  

Analysts with Mizuho predict Rezurock will generate about $36 million in 2022. The approval removes an “overhang” on the company’s shares and brings “greater conviction to the company’s pipeline execution capability,” the analysts wrote to clients on Friday. 

Friday’s approval adds to 2021’s impressive class of newly licensed medicines, which now includes more than 30 drugs.