US-based pharmaceutical company Kalvista Pharmaceuticals has reported positive data from a Phase III trial of sebetralstat, an oral plasma kallikrein inhibitor designed for on-demand treatment of hereditary angioedema (HAE).

The randomised, double-blind KONFIDENT trial assessed the safety and efficacy of 300mg and 600mg of sebetralstat versus those of placebo.

It enrolled 136 adult and adolescent subjects from 66 study sites in 20 countries.

These included subjects with type I and type II HAE who had experienced a minimum of two attacks in 90 days before enrolment.

Subjects treated each eligible attack with up to two doses of sebetralstat and could treat up to three attacks throughout the study.

The trial met all its primary and key secondary endpoints and demonstrated a favourable safety profile of the treatment in line with the placebo.

Results showed that attacks treated with both 300mg and 600mg doses of sebetralstat achieved significant and quick symptom relief versus placebo.

The median time to the start of relief from symptoms was 1.61 hours and 1.79 hours with 300mg and 600mg doses, respectively, against 6.72 hours with placebo.

There were no withdrawals due to adverse events or treatment-related serious adverse events reported.

KalVista CEO Andrew Crockett said: “We are thrilled to announce positive Phase III results for the KONFIDENT trial, which we believe position sebetralstat to become the first oral, on-demand therapy for the treatment of HAE.

“These clinically meaningful results represent a potentially significant advance for people living with HAE.

“If approved, sebetralstat may offer a compelling treatment option for patients and their caregivers given the long-standing preference for an effective and safe oral therapy that provides rapid symptom relief for HAE attacks.”

In March 2022, KalVista began the Phase III KONFIDENT trial of oral KVD900 for the treatment of HAE attacks.