Acer Therapeutics has received a complete response letter from the U.S. Food and Drug Administration (FDA) regarding its New Drug Application for Edsivo (celiprolol) for treatment of vascular Ehlers-Danlos syndrome (vEDS), the company announced.
In the letter, the FDA requested additional data from “an adequate and well-controlled trial” demonstrating that Edsivo can reduce “the risk of clinical events in patients with vEDS” before approval will be given, the company said in a press release.
“We remain committed to working closely with the FDA to fully understand its response,” said Chris Schelling, CEO and founder of Acer. “We expect to respond to the FDA in the third quarter of this year.”
vEDS, also called EDS Type IV, is considered the most severe form of EDS. Like other types of the disease, vEDS is characterized by impaired production of the tissue’s structural protein collagen due to mutations in the COL3A1 gene.
People with vEDS usually don’t have the more obvious symptoms linked to EDS, such as easily stretched skin (hyperextensibility) and abnormally wide ranges of joint motion (joint hypermobility). Instead, vEDS is often first noticed when there is a “catastrophic” event like a rupture of an artery or intestine. Approximately 70% of people with vEDS experience a major complication by the time they are 30 years old.
Edsivo was originally developed to treat hypertension (high blood pressure), but it is being investigated for vEDS as it is thought to promote the production of normal collagen in blood vessels. Also, because it lowers blood pressure in people with hypertension, Edviso may also lower the risk of blood vessels rupturing by reducing the amount of mechanical stress on affected vessels.
The trial enrolled 53 people with vEDS who were randomized to receive either Edsivo (200 mg orally twice daily) or a placebo.
Significantly fewer of those on treatment with Edsivo experienced a ruptured artery (20% vs. 50%), suggesting that Edviso could reduce the risk of serious cardiac events by 64%. Also, patients taking Edsivo were less likely to have intestinal or uterine ruptures (24% vs. 61%).
Despite these promising data, the FDA asked the company to conduct an additional clinical trial to further demonstrate Edsivo’s potential to reduce the incidence of clinical events in vEDS patients before it can be approved.
The FDA granted Edsivo orphan drug status for the treatment of vEDS in 2015, which is expected to provide support and guidance for the development of the investigational therapy.