European Commission Approves BioMarin’s PKU Drug Palynziq

Rare Daily Staff

The European Commission (EC) granted marketing authorization for BioMarin Pharmaceutical’s Palynziq for people 16 and older with phenylketonuria, a rare genetic disease with serious neurological and neuropsychiatric effects.

Phenylketonuria (PKU) is marked by an inability to break down Phe, an amino acid that is found in most forms of protein. It manifests at birth and results in a variety of cumulative toxic effects on the brain.  Left untreated, high levels of Phe become toxic and can affect the way a person thinks, feels, and acts. Infants in many countries are screened at birth to ensure early diagnosis and treatment to avoid intellectual disability and other complications.

Palynziq is the first enzyme substitution therapy approved in Europe to target the underlying cause of PKU by helping the body to break down Phe. In addition, the EC acknowledged that the phase 3 trial and extension study is suggestive of an improvement in inattention and mood symptoms. This is BioMarin’s second approved treatment for PKU.

On May 24, 2018, the U.S. Food and Drug Administration approved Palynziq to reduce blood Phe concentrations in adult patients with PKU.

“Palynziq is a new and promising treatment for the PKU community,” said Amaya Bélanger-Quintana, head of the Metabolic Department of the University Hospital Ramon y Cajal, Madrid, Spain. “Many adult PKU patients struggle daily with their special diet, leading many of them to relax or stop their treatment despite knowing the negative consequences this will have on to their well-being. Palynziq provides a new opportunity for adult PKU patients to attain the metabolic control their doctors and they want for themselves.”

The Palynziq EC approval was based on the totality of data from the Palynziq clinical development program including a phase 3 pivotal study, PRISM-2, which showed that a group of patients taking either 20 mg or 40 mg of Palynziq maintained mean blood Phe levels at a significant reduction to their pre-treatment baseline.

The approval was also based on data from an ongoing open-label extension study at 36 months, where patients being treated with Palynziq showed a sustained reduction in mean blood Phe over time, durability of response, and an increase in participants reaching important blood Phe thresholds.