Despite winning an alopecia areata approval for its drug Leqselvi in July, Sun Pharma will have to wait a while longer to launch its JAK inhibitor competitor to Eli Lilly and Incyte’s Olumiant and Pfizer’s Litfulo.
Sun, which had been plotting a mid-October launch for Leqselvi in the U.S., has been slapped with in an injunction blocking the rollout of the drug, the company said (PDF) in a filing to the BSE in India.
The decision, handed down in a New Jersey federal court, comes after Incyte earlier this year filed a lawsuit against Sun seeking to scupper Leqselvi’s launch.
Lilly and Incyte market the rival JAK inhibitor Olumiant for alopecia. In addition, Incyte sells the JAK med ruxolitinib, which is approved as Jakafi for certain blood cancers and graft-versus-host disease (GVHD), and in topical form as Opzelura for atopic dermatitis and vitiligo.
Thanks to the ruling, Sun is prevented from launching Leqselvi until it prevails in court or the patent in question in Incyte’s lawsuit—known as the ‘335 patent—expires. The company says it disagrees with the court’s decision and plans to “immediately appeal” the outcome. The patent is expected to expire toward the end of 2026.
Sun’s Leqselvi—which is also known as deuruxolitinib—is a deuterated form of Incyte’s Jakafi and Opzelura. Deuterated drugs replace hydrogen atoms with deuterium atoms in a bid to boost a medicine’s pharmacokinetic properties.
Incyte has claimed in court documents that Leqselvi is structurally identical to ruxolitinib and treads on the company’s ‘335 patent, which covers the use of ruxolitinib to treat immune-related diseases, skin disorders, myeloid proliferative disorders and cancer.
Incyte’s primary concern, according to the court documents, is that Leqselvi will be marketed at a lower price than Jakafi, prompting off-label prescriptions of Sun’s product to treat indications covered by Incyte’s JAK inhibitor tablet. Incyte has warned that it believes Leqselvi’s launch will trigger price erosion for Jakafi, lost licensing royalties from Lilly on Olumiant in alopecia, layoffs and decreased R&D opportunities.
Sun, for its part, argues that Lesqelvi doesn’t infringe on Incyte’s ‘335 patent and has branded the company’s off-label prescription concerns as speculative.
Sun’s Leqselvi snagged a green light in July, following in the footsteps of Lilly’s Olumiant, which became the first FDA-approved alopecia treatment in 2022. Pfizer’s Litfulo picked up a nod in the indication the following year.
Leqselvi is specifically approved in 8 mg tablets for adults with severe alopecia areata, which affects around 300,000 people in the U.S., according to Sun’s estimations. Sun got its hands on Leqselvi by way of its $576 million buyout of Concert Pharmaceuticals in January 2023.
Meanwhile, Olumiant and Jakafi continue to do gangbusters for Lilly and Incyte.
For all of 2023, Lilly reported Olumiant sales of around $923 million. Aside from alopecia, the drug is also approved to treat rheumatoid arthritis. Jakafi, for its part, brought home sales of roughly $2.6 billion last year, according to Incyte’s 2023 earnings report.