Patent Allowance Extends BioCryst’s Protection of Berotralstat for HAE

The U.S. Patent and Trademark Office (USPTO) issued a new allowance for a patent submitted by BioCryst Pharmaceuticals for berotralstat (BCX7353), an investigational therapy to treat hereditary angioedema (HAE).

The USPTO issued a notice of allowance to BioCryst, indicating future approval. Once approved, the new “composition of matter” patent will extend BioCryst’s protection over the active ingredient in berotralstat in the U.S. through October 2039.

“The extension of U.S. patent protection for berotralstat, through 2039, adds significant value to BioCryst,” Jon Stonehouse, CEO of BioCryst, said in a press release. “We look forward to the U.S. approval and launch of oral, once-daily berotralstat later this year.”

HAE is a rare genetic disease characterized by swelling attacks underneath the skin. These attacks are caused by excess production of a molecule called bradykinin, which is known to cause inflammation.

Berotralstat is a small molecule designed to block plasma kallikrein, a metabolic precursor to bradykinin. It is thought that blocking plasma kallikrein leads to a reduction of bradykinin levels in HAE patients.

The treatment has shown positive results in two clinical trials evaluating its safety and effectiveness in patients with type 1 or type 2 HAE, including the APeX-2 Phase 3 trial (NCT03485911) and the APeX-S Phase 2/3 trial (NCT03472040).

A total of 121 HAE patients were enrolled in the APeX-2 trial, in which participants received either a low dose (110 mg) or a high dose (150 mg) of berotralstat, or a placebo.

Results showed that both doses reduced HAE attacks in patients over a 24 week period by 30% (low dose) and 44% (high dose) compared to the placebo.

The study also suggested that attack severity may be reduced by berotralstat, as the monthly rate use of on-demand medication to treat attacks was reduced by 46.3% in the low dose group and 53.6% in the high dose group.

In the APeX-S trial, the majority of patients taking berotralstat did not experience swelling attacks during the first six months of the study.

The treatment was safe and well-tolerated in patients in both trials.

These positive clinical trial results led BioCryst to submit applications for the approval of berotralstat to regulatory agencies in the U.S., European Union, and Japan.

In the U.S., BioCryst submitted a new drug application, which is under review by the U.S. Food and Drug Administration. The application has a Prescription Drug User Fee Act action date of Dec. 3, meaning that a decision will be made by that date.

In Europe, the Committee for Medicinal Products for Human Use is reviewing berotralstat and is expected to make a decision before April 2021. The Japanese Pharmaceuticals and Medical Devices Agency also is reviewing an application for berotralstat, with a decision expected in the second half of this year.