UniQure recently announced plans to “expeditiously advance” its investigational hemophilia B gene therapy AMT-061 into a pivotal study in 2018. The announcement followed meetings the company had with both the U.S. Food and Drug Administration (FDA) and the European Medicines Agency.
AMT-061 is structurally very similar to another uniQure therapy known as AMT-060, which is also designed to treat patients with hemophilia B (factor IX deficiency). AMT-060 and AMT-061, the former of which is currently in phase 2/3 clinical trials, is manufactured in part with UniQure’s adeno-associated viruses (AAVs). AAVs are small viruses that do not actually cause disease, nor do they typically produce mild immune responses. Instead, AAVs are used as vectors (delivery vehicles) to introduce functioning genes into the liver cells, in this case the factor IX (FIX) gene for patients with hemophilia B. The goal of the trial is to trigger long-term FIX protein production through a single administration of the therapy. This could dramatically reduce the frequency of bleeding episodes in people with hemophilia B.
AMT-061 includes an additional gene known as FIX-Padua. According to a uniQure press release, FIX-Padua generates a protein that includes a single amino acid substitution that has been reported in multiple preclinical and nonclinical studies to elicit an approximate 8 to 9-fold increase in FIX activity compared to the wild-type FIX protein. The patent for FIX-Padua was acquired from Professor Paolo Simioni, an expert in hemophilia at the University of Padua in Italy. He is commonly recognized as the first to identify the FIX-Padua mutant.
“I have worked my entire career in the field of coagulopathies, and in my experience the innovation of FIX-Padua holds great promise for the treatment of hemophilia B,” said Professor Simioni. “Combined with the known safety profile of the AAV5 vector, this gene has the potential to significantly improve the health of hemophilia B patients. I look forward to working with uniQure as they advance what I believe will be the most effective gene therapy for patients suffering from hemophilia B.”
The FDA has granted expanded Breakthrough Therapy and Investigational New Drug (IND) designation to now include AMT-060 and AMT-061 – the former therapy was granted the FDA designation earlier in 2017, which the National Hemophilia Foundation reported on previously. Breakthrough drugs are put on a fast-track approval program and given intensive guidance from the FDA.
“I believe AMT-061 has the potential to be an important gene therapy for patients suffering with hemophilia B,” stated Steven Pipe, MD, professor of pediatrics and pathology and pediatric medical director of the hemophilia and coagulation disorders program at the University of Michigan. “Based on the data generated to date, AMT-061 may be the first gene therapy to provide durable, curative benefits to nearly all patients with hemophilia B, without the complications associated with capsid-related immune responses. I very much look forward to serving as an investigator in this exciting phase 3 program.”
The 2018 study is expected to be a single-dose, multi-center and multi-national trial investigating the efficacy and safety of AMT-061 administered to adult patients with severe or moderately severe hemophilia B. The primary objective of the trial is to evaluate AMT-061 for the prevention of bleeds, with secondary objectives to focus on additional evaluations of efficacy and safety.
Sources: uniQure press release and CNBC news, both dated September 19, 2017
