Netherlands-based Pharming Group has completed patient recruitment in its Phase 3 clinical study (Study 1310) evaluating the investigational drug Ruconest (recombinant human C1 inhibitor) for the treatment of acute angioedema attacks.

The company randomised 75 patients with hereditary angioedema (HAE) in its ongoing US pivotal Study 1310.

Pharming COO, Bruno Giannetti, said the final step to completion of the trial consists of an additional follow-up period of up to 90 days, depending on when patients experience a subsequent attack.

"At present, 53 of the 75 patients have experienced a repeat attack or achieved a 90-day attack-free period."

"However, it is a generally accepted assumption that approximately one to two attacks occur each month in otherwise untreated HAE patients, suggesting that those individuals in our study may typically experience a subsequent attack significantly sooner than 90 days post their randomised attack," Giannetti added.

The study will proceed until either all of the treated patients have received an open-label treatment for a subsequent HAE attack, or until 90 days have lapsed since their randomised attack, which will be followed by data analysis.

At present, 53 of the 75 patients have experienced a repeat attack or achieved a 90-day attack-free period, according to the company.

The positive study results will generate a $10m milestone payment to Pharming from its US partner Santarus.

Ruconest, which is produced through Pharming’s proprietary technology in the milk of transgenic rabbits, is approved in Europe for treatment of acute angioedema attacks in patients with HAE.

Ruconest is an investigational drug in the US and gained orphan drug status for the treatment of acute attacks of HAE.