US regulators have turned down Pharming’s application to expand the approved uses of Ruconest to include prophylaxis in patients with hereditary angioedema (HAE).

The group confirmed that it has received a Complete Response Letter (CRL) from the US Food and Drug Administration requesting that an additional clinical trial be carried out to further evaluate the effectiveness of the drug in this setting.

“While [the] decision is not what we were anticipating, we look forward to working with the FDA to generate additional clinical data required to enable access for patients to use Ruconest for HAE prophylaxis,” said Dr Bruno Giannetti, chief operations officer of Pharming.

“We see this as a minor setback…We will continue and have the resources to develop new innovative and more convenient administration options of Ruconest for acute treatment and prophylaxis of HAE to improve patient care as outlined in our recent capital market briefing in June,” said Sijmen de Vries, the firm’s chief executive.

Ruconest was first approved in Europe for the treatment of the rare genetic disorder HAE in 2010.

HAE causes debilitating, painful and sometimes life-threatening swelling in the body, affecting about one in 10,000 to one in 50,000 people worldwide.