The UK Medicines and Healthcare products Regulatory Agency (MHRA) has approved TMC Pharma's fosdenopterin (Nulibry) for the treatment of molybdenum cofactor deficiency (MoCD) type A.

This rare genetic disorder is characterised by the body's inability to produce cyclic pyranopterin monophosphate, leading to toxic sulphite accumulation that damages the brain. Symptoms apparent from birth include seizures, poor muscle tone and small head size.

The authorisation, which is based on a decision by the European Commission (EC) and advice from the Committee for Medicinal Products for Human Use, follows the EC decision reliance procedure.

Fosdenopterin is offered as a 9.5mg powder in solution for injection, administered intravenously through a catheter.

It has demonstrated benefits in five main studies enrolling 52 subjects with MoCD type A. These trials assessed the impact of fosdenopterin on survival following a treatment period of one year.

93% of subjects treated with fosdenopterin survived beyond one year, in contrast to a 75% survival rate in those who did not receive the treatment.

Initiating fosdenopterin treatment early, before the onset of significant brain damage, has been linked to preserved oral feeding abilities and enhanced growth, motor and cognitive development.

Pain, redness, discharge and inflammation were the most common side effects of the medicine linked to the catheter.

MHRA healthcare quality and access interim executive director Julian Beach stated: “Keeping patients safe and enabling their access to high quality, safe and effective medical products are key priorities for us.

“We’re assured that the appropriate regulatory standards for the approval of this medicine have been met. 

“As with all products, we will keep its safety under close review.”