Ventrus Biosciences to Merge With Assembly Pharmaceuticals

~ New Company, Assembly Biosciences, to Focus on First-in Class Technology for Treatment and Potential Cure of Hepatitis B Virus Infection, Affecting 350 Million Worldwide

~ Projected Multi-Billion Market Opportunity; No Curative Therapy Exists

~ Combined Teams Bring Experienced Leadership Capable of Driving Value

~ Anticipated Closing July 10, 2014, Pending Shareholder Approval

NEW YORK, SAN FRANCISCO and INDIANAPOLIS, May 19, 2014 (GLOBE NEWSWIRE) -- Ventrus Biosciences, Inc. has entered into a merger agreement with Assembly Pharmaceuticals, a privately held biopharmaceutical company, in an all-stock transaction. Upon the completion of the merger, the combined company will be renamed and trade on the Nasdaq Capital Market under the ticker "."

Once the merger is complete, the company will focus on the development of Assembly's novel, first-in-class small molecules to treat, and potentially cure, hepatitis B virus (HBV) infection. HBV is an underappreciated global epidemic with more than 350 million people worldwide chronically infected. Chronic HBV infection causes cirrhosis and liver failure, and it is a leading cause of liver cancer. Over 600,000 deaths each year are attributable to HBV. Current treatments can suppress the infection but require lifelong therapy since fewer than 10% of infections are currently cured.

"We believe this merger has tremendous potential. Assembly has amassed an enormous depth of scientific expertise and created a high quality drug discovery effort aimed at advancing its potentially curative therapies for HBV," said Dr. Russell Ellison, Chief Executive Officer and Chairman of Ventrus. "We believe combining the Ventrus and Assembly management teams, resources, and programs, will create a robust biopharmaceutical company with the capabilities to develop and commercialize this first-in-class curative approach to an underserved disease that afflicts hundreds of millions of people worldwide."

"This merger is an outstanding opportunity to progress our HBV platform and expeditiously bring a lead candidate into clinical development," said Derek Small, Chairman and Chief Executive Officer of Assembly. "Our board and management team believe that by joining with Ventrus, we can accelerate the creation of shareholder value as well as the timeline for development of our much-needed HBV therapeutics. We enthusiastically embraced this opportunity after carefully assessing multiple other attractive proposals to advance Assembly to the next stage."

Assembly has discovered a series of HBV Core Protein Allosteric Modulators (CpAMs) and has shown preclinical proof of principle with significant reductions in the HBV "S" antigen in experiments. HBV is a DNA-virus and Assembly's CpAMs target the function of intra-nuclear covalently closed circular DNA (a special DNA structure known as cccDNA). cccDNA drives establishment and survival of the virus, but no current therapies modulate its activity directly. Molecules that can modulate cccDNA are expected to have curative potential.

Assembly's CpAMs have shown they can selectively and potently reduce viral load, and the key viral antigens, HBV "S" antigen (HBsAg) and HBV "E" antigen (HBeAg). Reduction of HBsAg in patients is considered to be the best marker of a functional cure, and is a key clinical endpoint in development.

The proposed board and management team would consist of the following Ventrus and Assembly directors and officers, as well as one other director nominee:

Pursuant to the Merger Agreement, Ventrus will issue approximately 23 million shares of common stock to the Assembly stockholders. At the time of issuance, 20,322,760 of the shares will be issued common stock and 2,829,740 shares will be shares underlying stock options of Assembly. Consummation of this merger, expected to be completed by July 10, 2014, is subject to the approval by the Ventrus stockholders. This vote is required to meet Nasdaq requirements. The shares will represent approximately 49% of Ventrus' outstanding shares of common stock immediately after the Assembly merger, on a fully diluted basis.

Assembly Pharmaceuticals is a virology-focused biopharmaceutical company with a discovery platform and programs based on proprietary Core Protein Allosteric Modulators (CpAMs) for the treatment of viral infections, starting with hepatitis B (HBV). CpAMs can alter the activities of the HBV core protein, a unique viral protein with no human analogue that is involved in multiple stages of the HBV life cycle.  In contrast to current therapies that only suppress HBV, Assembly Pharmaceutical's CpAMs may have curative potential by eliminating the viral reservoir in infected individuals.

Ventrus BioSciences, Inc. is a development-stage specialty pharmaceutical company currently focused on the development of gastrointestinal (GI) products, including infections of the GI system. Ventrus believes it has completed clinical development of VEN 307 and has scheduled a meeting with the FDA on June 19, 2014 to discuss the filing of an NDA. Ventrus also has an early-stage program in microbiome therapeutics, VEN 310, which it is developing as an oral colonic delivery mechanism for bacteria, complex proteins, viral antigens and small molecules.