The EMA has granted orphan designation to AstraZeneca and MSD's selumetinib, a MEK 1/2 inhibitor, for the treatment of neurofibromatosis type 1 (NF1).
NF1 is an incurable genetic condition that affects one in 3,000 newborns worldwide. The severity of signs and symptoms associated with NF1 can be highly variable, are often mild-to-moderate and may include skin, nerve and skeletal manifestations.
"There is no cure for NF1, and current treatment choices for these patients are very limited," said Sean Bohen, AZ's Executive Vice President, Global Medicines Development and Chief Medical Office. "The granting of an orphan designation is a positive step forward for children with NF1 and their families."
The potential benefit of selumetinib in NF1 is being explored in the Phase I/II SPRINT trial in paediatric patients with inoperable NF1-related Plexiform neurofibromas (PNs). PNs are benign tumours on nerve sheaths that develop in 20-50% of patients, and as they continue to increase in number and size, cause moderate-to-severe morbidities such as pain, motor dysfunction and disfigurement..
Full results are expected later in 2018.
The NF1 gene provides instructions for making a protein called neurofibromin, which negatively regulates the RAS/MAPK pathway, helping to control cell growth, differentiation and survival. Mutations in the NF1 gene may result in dysregulations in RAS/RAF/MEK/ERK signalling, which can cause cells to grow, divide and copy themselves in an uncontrolled manner, and may result in tumour growth. Selumetinib inhibits the MEK enzyme in this pathway, potentially leading to inhibition of tumour growth.
It is also being explored as a monotherapy and in combination with other treatments in other ongoing trials.
AZ and MSD announced a global strategic oncology collaboration in July 2017 to co-develop and co-commercialise selumetinib and Lynparza, the world's first PARP inhibitor. Working together, the companies will develop Lynparza and selumetinib in combination with other potential new medicines and as monotherapies. Independently, the companies will develop Lynparza and selumetinib in combination with their respective PD-L1 and PD-1 medicines.