The US Food and Drug Administration (FDA) has lifted the clinical hold on KalVista Pharmaceuticals’ Phase II KOMPLETE clinical trial of KVD824 as oral prophylactic therapy for hereditary angioedema (HAE).

The move comes after the regulatory agency reviewed KalVista responses to its request for additional information and analysis linked to some preclinical studies of the drug.

Modifications to the Phase II trial protocol have also been made by the company.

Currently, KalVista is working closely with trial investigators and study centres to progress with all trial activities soon.

The randomised, double-blind, parallel-group Phase II trial will assess twice-daily 300mg, 600mg and 900mg doses of KVD824 versus placebo for 12 weeks.

It plans to enrol a total of 48 subjects at more than 30 sites in 13 countries, with US site initiations underway.

Participants will be categorised into four equal groups after they experience at least three attacks in an eight-week run-in period.

The rate of HAE attacks confirmed by investigators during the therapy period will be the trial’s primary goal.

The proportion of subjects with no investigator confirmed HAE attacks and the rate of investigator confirmed HAE attacks that need standard treatment will be included as secondary goals.

KalVista Pharmaceuticals CEO Andrew Crockett said: “The execution of KOMPLETE, our Phase II clinical trial for KVD824 as a potential oral prophylactic therapy for HAE, is expected to accelerate now that we can also proceed at our US trial sites.

“Progress continues worldwide, with regulatory submissions complete in all of the countries where the trial will be conducted.”

Earlier, KalVista reported results from first-in-human and formulation trials of KVD824 that were performed in the UK.

So far, 121 subjects were treated with single doses of KVD824 up to 1280mg and up to 14 days of twice-daily dosing of 600mg and 900 mg.

Results from the Phase I trials showed that KVD824 upholds the plasma concentrations that are estimated to be needed to offer efficacy in line with approved injectable treatments.

In both trials, adverse event rates were similar in the placebo and active groups without any serious adverse events noted.

In 2018, KalVista started a Phase ll proof-of-concept trial to assess the safety, tolerability and efficacy of KVD001 for the treatment of diabetic macular oedema.