PharmAthene said today it called off its planned merger with Theraclone Sciences, an all-stock, merger-of-equals deal—as well as a special meeting of PharmAthene stockholders set for Tuesday to formalize the transaction.
PharmAthene did not state a reason for its about-face, in a statement that acknowledges it will pay Theraclone a $1 million termination fee. But the aborted merger comes about a week after Theraclone disclosed on November 27 it was turned down for funds from the Biomedical Advanced Research and Development Authority (BARDA) to advance development of its recombinant fully human monoclonal antibody TCN-032 into Phase II trials for serious influenza, including pandemic flu.
At the time, Theraclone CEO Clifford J. Stocks said his company remained “encouraged by the potential of TCN-032 for two current indications—to help combat pandemic flu as well as the commercial potential to treat patients who are hospitalized with serious influenza infections.” Stocks noted the company found a development partner for TCN-032 in Japan, and would “continue to evaluate opportunities to advance TCN-032 with other potential strategic partners for commercial markets.”
Theraclone’s development pipeline includes the monoclonal antibody TCN-202, for which it launched a Phase IIa proof-of-concept study in September for prevention of human cytomegalovirus infection in solid organ (kidney) transplant recipients. Up to 20 renal transplant recipients will receive TCN-202 during the first 10 weeks post-transplant, with the study’s primary objective being to assess the effect of TCN-202 on prevention of CMV infections during the first three months after transplant. Data is expected in the second half of 2014.
PharmAthene and Theraclone announced their merger August 1, without disclosing the price but trumpeting the deal as enabling the creation of a combined company focused on developing vaccines against infectious diseases and human monoclonal antibody (mAb) drugs against cancer.
The combined company, to have been headed by Stocks, laid out plans to pursue development of four clinical-stage product candidates targeting high-value commercial and government markets, as well as a discovery pipeline with four preclinical programs and multiple discovery candidates, along with three products being developed with partners.
Those products include PharmAthene’s SparVax®, a next-generation recombinant protective (rPA) anthrax vaccine; rBChE bioscavenger, a medical countermeasure for nerve agent poisoning by organophosphorous compounds; and Valortim®, a fully human monoclonal antibody for the prevention and treatment of anthrax infection.
Last month, PharmAthene President and CEO Eric I. Richman said in releasing quarterly results that the company was on track to launch the planned Phase II clinical trial of SparVax, “which we anticipate will begin by the end of the year.” SparVax development was slowed down by an FDA clinical hold lifted in May; the agency requested PharmAthene provide additional stability data for both its engineering and GMP lots of U.S. manufactured Final Drug Product, as well as additional information about the intended stability indicating assays.