Conatus Announces Phase 2b ENCORE-PH Trial Failure for NASH Drug Emricasan, Shares Plunge Over 56%

VCBeat (WeChat ID: vcbeat) learned from overseas sources that on December 5, 2018, local time, Conatus Pharmaceuticals Inc. (NASDAQ: CNAT), a biotechnology company based in Florida, USA, announced on its official website that emricasan, its investigational drug for non-alcoholic steatohepatitis (NASH), failed to meet the primary endpoint in its ENCORE-PH Phase 2b clinical trial. This marks the company’s second clinical trial failure in the field of liver disease therapeutics since April of this year. Following the announcement, Conatus’s stock price plummeted by more than 56% to $1.94 in pre-market trading.

Image source: Conatus official website

Previously, the remarkable potential demonstrated by emricasan in a small mid-stage trial thrust Conatus into the industry spotlight and attracted the attention of pharmaceutical giant Novartis. In 2016, the two companies signed an agreement to jointly develop emricasan. Last year, Novartis paid Conatus more than $50 million to secure global development and commercialization rights for emricasan. Under the terms of that agreement, Novartis could pay Conatus up to $650 million in milestone payments upon the achievement of specified development, regulatory, and commercialization milestones. Unfortunately, however, Conatus experienced two consecutive trial failures within an eight-month period from April to December this year.

Emricasan is an orally active caspase inhibitor designed to reduce the activity of enzymes that can lead to inflammation and apoptosis. Conatus believes that by reducing the activity of these enzymes, this caspase inhibitor has the potential to block the progression of various diseases. To date, Conatus has studied emricasan in approximately 700 patients across 17 completed clinical trials involving a broad spectrum of liver diseases. Previously, emricasan demonstrated favorable effects on improving liver function test results and anti-fibrotic therapy in multiple Phase 2 clinical trials.

The ENCORE-PH Phase 2b trial, which triggered the collapse of Conatus Pharmaceuticals’ stock price, was initiated in the fourth quarter of 2016. In this trial, researchers enrolled 263 patients with nonalcoholic steatohepatitis (NASH), who were randomized to receive different doses of emricasan or placebo for 24 weeks. At the end of the observation period, clinical results demonstrated that emricasan was not superior to placebo in improving the hepatic venous pressure gradient (HVPG), a key factor contributing to the study’s failure to meet its primary endpoint.

With the results of the two remaining emricasan trials expected to be released next year, Conatus believes it still has an opportunity to gather the clinical outcomes needed for its pivotal program. However, the consecutive failures of two clinical trials have led investors to hold a pessimistic view of Conatus’s prospects.

Conatus, founded in 2005 and headquartered in California, USA, is a clinical-stage biotechnology company. The company is dedicated to developing innovative therapies for various liver diseases and cancers. Conatus went public on the NASDAQ in 2013 with an opening price of $11 per share, under the stock ticker symbol: CNAT.