Enanta Pharmaceuticals has secured the Fast Track designation from the US Food and Drug Administration (FDA) for EDP-323 L-protein inhibitor to treat respiratory syncytial virus (RSV).
Enanta, engaged in the development of small molecule drugs for viral infections, said that the Fast Track status will expedite the development and review of EDP-323, which is still in development.
It will also enable more frequent communication with the US health regulator and eligibility for FDA’s programmes like priority review and rolling review, if the necessary criteria are fulfilled.
Enanta Pharmaceuticals SVP and chief medical officer Scott Rottinghaus said: “Receiving Fast Track designation from the FDA underscores EDP-323’s potential as a once-daily, oral therapeutic for the treatment of this deadly virus and reflects the pressing need for a highly potent, direct antiviral to treat RSV, particularly for high-risk populations.
“Given that EDP-323 has shown sub-nanomolar potency against several RSV-A and RSV-B strains in vitro and is not expected to have cross-resistance to other classes of inhibitors, we believe it could be used as a monotherapy or in combination with other RSV mechanisms to potentially broaden the addressable RSV patient populations or the treatment window.
“We believe this designation will be a valuable component of our clinical and regulatory strategy as we progress EDP-323 in development.”
The biotechnology company said that a phase 1 double-blind, placebo-controlled trial is being conducted to evaluate the safety, tolerability, and pharmacokinetics (PK) of the L-protein inhibitor.
EDP-323 is backed by in vitro data that showed a significant reduction in RSV replication with picomolar potency in main human bronchial epithelial cells against RSV A and B. It also demonstrated consistent potency across a variety of RSV clinical isolates in different cell types.
The treatment with EDP-323 in a mouse model of RSV infection was linked to dose-dependent drops in lung virus load, decreased lung immunopathology, and drops in pro-inflammatory cytokines.
Furthermore, EDP-323 is claimed to have had favourable oral bioavailability with good plasma exposures in preclinical species and pharmacokinetic properties. This supports the once-daily, oral dosing in humans.
Enanta Pharmaceuticals said these findings suggest that EDP-323 is an effective inhibitor of RSV replication and can be a once-daily, oral antiviral therapy for RSV.
