In the latest setback to Vical/Astellas partnership, lead CMV vaccine fails a pivotal PhIII study
When Vical’s lead vaccine flopped in a Phase II herpes study in 2016, the biotech and its partners at Astellas switched focus to a pivotal Phase III trial in hemotopoietic stem cell transplant recipients. Today, the partners say that too has failed.
The cytomegalovirus vaccine ASP0113 is designed to induce an immune response against the CMV virus with the encoded CMV phosphoprotein 65 and glycoprotein B antigens. The DNA vaccine failed both the primary composite endpoint and the secondary endpoints: the former being overall mortality and CMV end-organ disease through the first year following the transplant; the latter measured time to first CMV viremia and time to first use of adjudicated CMV-specific antiviral therapy.
The execs at both companies were straightforward about the failed study, which was conducted among 514 patients across 70 sites in 11 countries. Investors, though, were rattled by the latest damage. Vical’s shares plunged 32% in pre-market trading.
“The Phase III trial outcome is disappointing,” said Vical CEO Vijay Samant. “Astellas and Vical employees, the investigators and study site personnel did an outstanding job conducting this study, but unfortunately, the vaccine was unable to provide protection against all-cause mortality in this very difficult-to-treat patient population.”
Astellas picked up rights to develop and commercialize the vaccine in a $135 million deal back in 2011, though the lack of progress means San Diego-based Vical has yet to cash in all the milestone payments.