The US Food and Drug Administration (FDA) has granted orphan drug designation to Coversin as a treatment for paroxysmal nocturnal hemoglobinuria (PNH).
Coversin is a recombinant small protein (16,740 Da) derived from a native protein found in the saliva of the Ornithodoros moubata tick.
The drug is a second-generation complement inhibitor that acts on complement component C5, preventing release of C5a and formation of C5b-9 (also known as the membrane attack complex).
Coversin is being developed by Akari Therapeutics.
In vitro experiments have shown that Coversin inhibits red blood cell lysis in PNH, and Coversin can achieve full complement inhibition in the blood of PNH patients who are resistant to eculizumab.
In a phase 1a trial of healthy volunteers, Coversin completely inhibited complement C5 activity within 12 hours of administration.
Akari Therapeutics is currently conducting a phase 1b study of Coversin in healthy volunteers and is enrolling patients with eculizumab-resistant PNH in a phase 2 trial.
The company has also been administering Coversin to a patient with eculizumab-resistant PNH. Thus far, Coversin has prevented hemolytic episodes and improved disease symptoms in this patient. The only drug-related adverse event has been occasional local and transient irritation at the injection site.
“We have continued to see complete complement inhibition and symptom control in a PNH patient with resistance to eculizumab, who has been self-administering subcutaneous Coversin for over 7 months,” said Gur Roshwalb, MD, CEO of Akari Therapeutics.
“We believe that Coversin, when approved, could provide important benefits for all patients with PNH.”
Coversin is also being studied in atypical hemolytic uremic syndrome and Guillain Barré syndrome.
About orphan designation
The FDA grants orphan designation to drugs and biologics intended to treat, diagnose, or prevent diseases/disorders that affect fewer than 200,000 people in the US.
The designation provides incentives for sponsors to develop products for rare diseases. This may include tax credits toward the cost of clinical trials, prescription drug user fee waivers, and 7 years of market exclusivity if the product is approved.
