Pharming’s investigational treatment for activated phosphoinositide 3-kinase delta syndrome (APDS) has been granted orphan drug designation from the European Commission.

The designation awarded to Pharming’s drug, leniolisib, was based on a positive opinion from the Committee for Orphan Medicinal Products (COMP) of the European Medicines Agency (EMA).

Previously, leniolisib was granted orphan drug designation by the US Food and Drug Administration in January for APDS.

APDS is caused by mutations in the PIK3CD gene (type 1 APDS) or PIK3R1 (type 2 APDS) that activate phosphoinositide 3-kinase-delta (PI3Kδ). Leniolisib is a small molecule PI3Kδ inhibitor with immunomodulating and potentially anti-neoplastic activities.

The condition is defined as an ultra-rare, genetic, primary immunodeficiency disease characterised by increased susceptibility to recurrent and severe bacterial and viral infections, chronic benign lymphoproliferation and autoimmune disease.

“We are pleased to have received orphan drug designation from the European Commission, an important milestone in the development of leniolisib for the treatment for APDS, an ultra-rare and debilitating disease,” said Sijmen de Vries, chief executive officer of Pharming.

“With no currently approved treatment, leniolisib has the potential to address a significant unmet need for patients with APDS. Leniolisib is currently being studied in a registration-enabling phase II/III trial and remains, subject to regulatory approval, on track to launch in H2 2022,” he added.

According to Pharming, the APDS incidence rate globally is currently estimated to be 1-2 people per million.