AstraZeneca and MSD have announced the granting of Breakthrough Therapy Designation (BTD) by the US Food and Drug Administration (FDA) for its MEK 1/2 inhibitor and potential new medicine selumetinib.

The BTD is for the treatment of paediatric patients aged three years and older with neurofibromatosis type 1 (NF1) symptomatic or progressive, inoperable plexiform neurofibromas (PN), a rare, incurable genetic condition.

José Baselga, executive vice president, Research and Development, Oncology, said: “Selumetinib shows promise in the treatment of NF1-related plexiform neurofibromas, a rare and debilitating disease with no approved medications to date. The Breakthrough Therapy Designation acknowledges the significant unmet need of these patients and the potential benefit of selumetinib in this setting.”

Selumetinib was already granted Orphan Drug Designation for the treatment of NF1 by the US FDA in February 2018, and the European Medicines Agency in August 2018.

The co-development of the drug is part of AstraZeneca and MSD’s global strategic oncology collaboration, which also focuses in the world’s first PARP inhibitor Lynparza (olaparib).

NF1 is an incurable genetic condition that affects one in 3,000 to 4,000 people. It is caused by a spontaneous or inherited mutation in the NF1 gene and is associated with many symptoms, including soft lumps on and under the skin (cutaneous neurofibromas), skin pigmentation and in 20-50% of patients, tumours which develop on the nerve sheaths (plexiform neurofibromas).

This development marks the ninth BTD that AstraZeneca has received from the FDA since 2014.