FDA Denies Acer’s Appeal for Edsivo, a Potential Vascular EDS Therapy

The Office of New Drugs (OND) of the U.S. Food and Drug Administration (FDA) has denied an appeal from Acer Therapeutics regarding Edsivo (celiprolol), an investigational therapy for vascular Ehlers-Danlos syndrome (vEDS).

Further clinical studies will be needed before the investigational therapy can be resubmitted for regulatory review.

vEDS is generally considered the most severe form of EDS. Like other types of the disease, vEDS is characterized by limited production of collagen, a protein that helps tissues maintain their structure. Edsivo, originally developed to treat hypertension (high blood pressure), is being investigated for vEDS because it may promote the production of collagen in blood vessels, thereby reducing blood pressure and avoiding blood vessel rupture.

Acer submitted a new drug application (NDA) for Edsivo as a vEDS treatment to the FDA at the end of 2018. The application was largely based on results from a Phase 4 clinical trial (NCT00190411), showing that, compared to a placebo, treatment with Edsivo (200 mg taken by mouth twice per day) significantly reduced the rate of artery ruptures (20% vs. 50% in the placebo group), and of intestinal or uterine ruptures (24% vs. 61% in the placebo group).

However, the FDA issued a complete response letter denying the application in June 2019. At the time, the regulatory agency requested additional clinical trial data demonstrating the efficacy of Edsivo as a vEDS treatment before the therapy could be considered for approval.

At the end of 2019, Acer issued a Formal Dispute Resolution Request (FDRR), a formal appeal of the FDA’s initial denial.

Now, the FDA responded to the FDRR. The agency reaffirmed its earlier decision that further clinical trial data are needed before Edsivo could be approved for vEDS.

In its response letter, the OND described some possible paths that Acer could explore in order to acquire the necessary data to support a resubmission.

“We appreciate the OND’s time and attention in thoughtfully considering this FDRR,” Chris Schelling, founder and CEO of Acer, said in a press release. “While neither resubmission nor the prospect of approval of the Edsivo NDA is assured, we are evaluating our possible next steps with the goal of resubmission of the Edsivo NDA.”

Acer expects to be able to continue operations at least until the end of 2020. After the initial FDA rejection, the company went through an organizational restructuring in an attempt to conserve resources.