Enanta Pharmaceuticals Inc (NASDAQ: ENTA) stock fell 11.85% on June 16th, 2019 but corrected over 1.5% on 17th June, 2019 (as of 12:10 pm GMT-4: Source: Google finance). The company, that is into creating small molecule drugs for viral infections and liver diseases, had announced the topline results that showed EDP-938 achieved highly statistically significant (p<0.001) reductions in viral load and in resolution of clinical symptoms compared to placebo in its Phase 2a human challenge study of EDP-938 in healthy adults infected with respiratory syncytial virus (RSV). ENTA plans to initiate the first Phase 2b study by the end of calendar 2019 in adult outpatients with confirmed RSV infections. The therapy, EDP-938, developed for treating respiratory syncytial virus (RSV) infection which currently has no available treatment, also helped improve symptoms in patients compared to placebo, the company said.
An average of 57,527 children younger than 5 years and 177,000 adults older than 65 years are hospitalized due to RSV infections every year, according to the Centers for Disease Control and Prevention.
RSV could lead to serious lung infections and even death in babies and the elderly who have a weaker immune system. Enanta’s EDP-938 works by inhibiting the replication of the RSV virus within the infected cell, while certain other experimental treatments attempt to stop the virus from infecting the cell.
Meanwhile, the Phase 2a study was a randomized, double-blind, placebo-controlled, human challenge study in healthy adult subjects inoculated with RSV. A total of 115 subjects were enrolled and inoculated with the challenge virus. Once RSV infection was confirmed, participants were then randomized: 38 in the placebo arm, 39 in the 600 mg QD arm (one subject was randomized, but never dosed), and 38 in the 500mg LD plus 300mg BID arm.
EDP-938 demonstrated good pharmacokinetics, and mean trough levels of drug were maintained at approximately 20-40x above the in vitro EC90 for RSV-infected human cells. Overall, EDP-938 was generally safe and well tolerated. EDP-938 demonstrated a favorable safety profile over 5 days of dosing through Day 28 of follow-up, comparable to placebo for both dosing groups. There were no serious adverse events and no discontinuation of study drug. The study will be presented at a future medical conference.
Additionally, drugmakers such as Regeneron Pharmaceuticals Inc and Johnson & Johnson have abandoned certain programs to find a treatment for the condition, and an experimental vaccine developed by Novavax Inc had failed a late-stage trial, earlier this year.