Even as it’s tangled in a rare disease patent dispute, CSL Behring has secured FDA approval for Haegarda to prevent HAE attacks in adolescents and adults. Haegarda is the first C1 esterase inhibitor for under-the-skin attack prevention, a method Shire says violates a patent it received back in April.
On the same day Shire received its patent for subcutaneous HAE treatment with a composition comprising a C1 esterase inhibitor, among other stipulations, the Irish drugmaker sued Australia’s CSL to block its Haegarda launch. Shire markets HAE meds Cinryze, Firazyr and Kalbitor already, and it's working on a subcutaneous prophylactic C1 esterase inhibitor dubbed SHP616, among other candidates.
At the time, CSL countered that it "remains highly confident" its drug "does not infringe any valid claim of the Shire ViroPharma patent and will vigorously defend against the claims." The company says Haegarda “is the product of independent research and development work at CSL Behring.”
On Friday, a CSL spokesperson said the company expects to have its med available to U.S. patients during the third quarter of this year. Pricing details haven't been released, she added.
"CSL is highly confident in our product and the safety and efficacy Haegarda offers patients," CSL's spokesperson said. "We cannot comment on the patent suit at this time.
About 6,000 to 10,000 people in the U.S. suffer from HAE, according to the FDA, a condition caused by shortages of a plasma protein dubbed C1 esterase inhibitor. Patients can suffer from rapid swelling attacks caused by stress, surgery or infection.
CSL’s Haegarda won an Orphan Drug designation, providing development incentives to drugmakers who work on therapies for rare diseases. The drug is prepared from large pools of U.S. plasma donors and is indicated for routine use to prevent attacks, rather than in response to an HAE attack.
The approval provides patients with a new option, FDA’s Center for Biologics Evaluation and Research director Peter Marks said in a statement; he added that “the subcutaneous formulation allows patients to administer the product at home to help prevent attacks."
In its lawsuit, Shire says the extensive efforts CSL has undertaken to get ready for its pending Haegarda launch violate its patent. Among those efforts are phase 3 trials, a U.S. marketing application, hiring personnel and early manufacturing. Shire's Cinryze, a C1 esterase inhibitor injection, pulled in $680 million in global sales last year.