BioCryst Starts Long-Term Trial of BCX7353’s Ability to Prevent Hereditary Angioedema Attacks

A long-term clinical trial testing BCX7353’s ability to prevent hereditary angioedema (HAE) attacks is dosing its first group of participants, BioCryst Pharmaceuticals announced.

“Initiation of the APeX-S trial is an important milestone to support filing and approval of BCX7353, and furthers our core strategy of bringing a once-daily, oral prophylactic treatment to HAE patients,” Jon Stonehouse, the chief executive officer of BioCryst, said in a press release.

In hereditary angioedema, mutations of the C1 inhibitor lead to excessive bradykinin production. This inflammatory mediator causes vasodilatation, vascular leakage, and subsequent angioedema and pain.

BCX735, an oral inhibitor of plasma kallikrein, is believed to reduce the amount of bradykinin in these patients. This would make it a promising approach for treating and preventing angioedema attacks.

The APeX-S trial was designed to determine the safety and efficacy of BCX7353 as a preventive treatment for hereditary angioedema patients.

The open-label trial is set to enroll 160 patients with type 1 or type 2 HAE. They will receive one of two BCX7353 doses — 110 mg or 150 mg once a day.

Participants will receive the treatment for 48 weeks (11 months), after which researchers will assess its long-term safety, durability of response, and effect on quality of life.

Patients who participated in a previous clinical trial of BCX7353 will be enrolled first, followed by those who have never had BCX7353 therapy.

BioCryst is also conducting the proof-of-concept Phase 2 ZENITH-1 clinical trial. It is evaluating the potential of BCX7353, administered as an oral liquid, to prevent acute angioedema attacks.

“Long-term safety results from this trial will supplement efficacy and safety data from the APeX-2 Phase 3 trial, which is also expected to commence in the first quarter of 2018. The ability to run these trials concurrently is beneficial, as it may allow us to more rapidly get this important medicine into the hands of patients who are seeking a better quality of life by eliminating their current injection-based treatment programs,” Stonehouse said.

“The launch of this trial has brought within arm’s reach the fulfillment of the long-standing need of HAE patients for a convenient, easy-to-administer, oral remedy, developed on purpose for the prophylaxis [prevention] of angioedema attacks,” said Dr. Henriette Farkas, the principal investigator of the APeX-S trial.