Orphan Drug Trial to Begin for Sanfilippo B Syndrome Therapy

Novel drug delivers enzyme replacement therapies directly to the brain.

The first patient has been enrolled in a phase 1/2 trial for BioMarin Pharmaceutical’s experimental drug BMN 250, which has been granted orphan drug designation by the European Commission to treat Sanfilippo B syndrome (MPS IIIB).

BMN 250 is an investigational enzyme replacement therapy that uses a novel fusion of recombinant human alpha-N-acetyglucosaminidase (NAGLU) with a peptide derived from insulin-like growth factor 3 (IGF2).

“Children with Sanfilippo syndrome need therapies that target the root cause of this fatal genetic disease that currently has no approved treatment options,” said Jill Wood, co-founder and treasurer, Jonah's Just Begun Foundation to Cure Sanfilippo. “We applaud companies like BioMarin who are bringing scientific research into the clinic. This is a critical first step to finding potential treatments.”

The BMN 250 development program involves 2 multicenter, international clinical trials. BMN 250-901 is an observational study that examines the progression of MBS IIIB over time in children.

BMN 250-201 is a phase 1/2 study broken into 2 parts. Part 1 focuses on the safety and dose escalation, while part 2 uses eligible patients from the BMN 250-901 observational study in addition to continued treatment of patients from Part 1 of the study.

To test the efficacy of BMN 250, changes in disease progression will be compared in the observational BMN 250-901 study versus those in part 2 of the BMN 250-201 phase 1/2 treatment study.

“Sanfilippo B has long been a difficult condition to treat due to challenges in effectively delivering a therapy that bypasses the blood brain barrier to address the underlying cause of the disease,” said Hank Fuchs, MD, chief medical officer at BioMarin. “BMN 250 is designed to overcome these challenges by leveraging our proprietary technology to deliver enzyme replacement therapies directly to the brain.

“BMN 250 is the result of building upon our almost 2 decades of experience in developing treatments for MPS and our most recent experience with an intracerebroventricular delivery approach, which we have used with another experimental enzyme replacement therapy delivered directly to the brain to treat a form of Batten disease.”