Study Findings Published by Collaborators in Nature
–Theraclone Seeking Licensees and Strategic Alliances for the HIV Program–

SEATTLE, WA, USA I November 5, 2013 I Theraclone Sciences, Inc., a therapeutic antibody discovery and development company, today announced that collaborators published data in the October 30th issue of Nature regarding an antibody discovered by Theraclone and the International AIDS Vaccine Initiative (IAVI) with significant potency and breadth against human immunodeficiency virus (HIV). In the study, titled “Therapeutic efficacy of potent neutralizing HIV-1-specific monoclonal antibodies in SHIV-infected rhesus monkeys,” researchers demonstrated that a single administration of PGT121 alone and in combination with an additional monoclonal antibody potently reduced levels of simian HIV below detection for weeks after dosing. Importantly, in this study, the virus did not appear to develop resistance to PGT121.

“The discovery of broadly neutralizing antibodies, or bNAbs, such as PGT121, which have the ability to target a large proportion of all major circulating HIV subtypes, has rekindled the pursuit of antibodies in the prevention and treatment of HIV and, according to the investigators in the study, the findings encourage the investigation of monoclonal antibody therapy for HIV-1 in humans,” said Kristine Swiderek, Ph.D., CSO of Theraclone Sciences.

As described in an earlier Nature publication in 2011, PGT121, along with a large panel of other anti-HIV bNAbs, was discovered with Theraclone’s proprietary I-STAR™ technology, which mines the human memory B-cell repertoire of naturally-occurring human antibodies to uncover those with exceptional biological activity. The result is a broadly protective, fully human monoclonal antibody with therapeutic potential to combat HIV infection.

In 2009, Theraclone and IAVI agreed to collaborate to use Theraclone’s novel I-STAR technology for isolating potent monoclonal antibodies to HIV that are broadly neutralizing from the blood of certain HIV-infected individuals who had seemingly developed a protective immune response. Such antibodies have the potential to neutralize many of the types of HIV in circulation worldwide. IAVI retains rights to develop HIV vaccines based on these antibodies, and Theraclone holds and controls the rights to develop therapeutics based on these antibodies.

“This research highlights the power of our I-STAR technology to discover potent antibodies from individuals that have developed a potent and broadly protective immune response in historically difficult-to-treat diseases,” said Clifford J. Stocks, Chief Executive Officer of Theraclone. “At this time, we are seeking licensees and strategic partnerships to capitalize on PGT121 and other HIV antibodies which represent a significant opportunity for advancements in the treatment of HIV.”

About Theraclone

Theraclone is a biopharmaceutical company focused on the discovery and development of novel, monoclonal antibody therapeutics for diseases that are devastating for patients and their families and which are a significant threat to human health. Theraclone leverages its proprietary antibody discovery technology, I-STAR™ (In-Situ Therapeutic Antibody Rescue), to identify rare human antibodies that may be developed into antibody product candidates that are potentially safer and more effective than current therapies. Theraclone has a portfolio of innovative antibodies in clinical and preclinical development targeting serious medical conditions with a significant unmet medical need and a primary focus on infectious disease and cancer, which include:

  • TCN-032 – a recombinant fully human monoclonal antibody for the treatment of patients hospitalized with serious influenza
  • TCN-202 – a recombinant fully human monoclonal antibody for the treatment and prevention of cytomegalovirus, or CMV infections

For more information about Theraclone, please visit www.theraclone-sciences.com. On August 1, 2013, Theraclone and PharmAthene (NYSE MKT: PIP) announced a definitive merger agreement.

About PharmAthene

PharmAthene is a leading biodefense company engaged in the development and commercialization of next generation medical countermeasures against biological and chemical threats. PharmAthene’s current biodefense portfolio includes the following product candidates:

  • SparVax® – a next generation recombinant protective antigen (rPA) anthrax vaccine
  • rBChEbioscavenger – a medical countermeasure for nerve agent poisoning by organophosphorous compounds, including nerve gases and pesticides
  • Valortim® – a fully human monoclonal antibody for the prevention and treatment of anthrax infection

In addition, in May 2013, the Delaware Supreme Court issued its ruling on the appeal in our litigation with SIGA Technologies, affirming the Court of Chancery’s finding that SIGA was liable for breach of contract, reversing its finding of promissory estoppel, and remanding the case back to the Court of Chancery to reconsider the appropriate remedy and award of attorney’s fees and expert witness costs in light of the Supreme Court’s opinion. For more information about PharmAthene, please visit www.PharmAthene.com.

SOURCE: Theraclone