Pfizer has begun testing investigational gene therapy fidanacogene elaparvovec for the treatment of haemophilia B, triggering a race against Dutch biotech UniQure.
Pfizer’s phase III programme will test the Spark Therapeutics-developed compound after it gathers safety and efficacy data of current factor IX prophylaxis replacement therapy as a lead-in study.
This data will then serve as the within-subject control group for patients that enrol into the next part of the study.
Previous data has shown promise for the pharma giant, with results from an earlier phase I/II trial reporting that just one out of 15 patients experienced a bleed four weeks after treatment, showing ‘immense promise for the use of this potential one-time treatment option’.
Katherine High, president and head of research and development, Spark Therapeutics, said: “The initiation of the Phase III programme marks an important milestone toward our goal of one day potentially eliminating spontaneous bleeding.”
If all goes well for Pfizer, its therapy might free patients of regularly injecting an engineered version of clotting factor IX – which people with haemophilia B lack – as fidanacogene elaparvovec could allow patients to produce their own factor IX once treated.
Brenda Cooperstone, senior vice president and chief development officer, rare disease, Pfizer Global Product Development, said: “With the lead-in study now open and actively recruiting patients, we are excited to begin our Phase 3 programme evaluating fidanacogene elaparvovec for the treatment of hemophilia B.
“We look forward to the opportunity to continue the progress achieved by Spark Therapeutics for patients living with hemophilia B.”
The news of the phase III programme comes hot on the heels of UniQure’s haemophilia B gene therapy trial, which last month enrolled its first patient for its candidate AMT-061.
Now the race is on to potentially disrupt a multibillion-dollar market, but who will come out on top remains to be seen.