ViroPharma Incorporated (Nasdaq: VPHM) announced that its Phase 3 trial evaluating maribavir used as prophylaxis in allogeneic stem cell, or bone marrow, transplant (SCT) patients did not achieve its primary endpoint.
In the primary analysis, there was no statistically significant difference between maribavir and placebo in reducing the rate of CMV disease. In addition, the study failed to meet its key secondary endpoints. Maribavir was generally well tolerated in this clinical study.
“We are extremely disappointed by the outcome of this pivotal study,” said Vincent J. Milano, ViroPharma’s president and chief executive officer. “We just received these data and there are far more questions than answers; we still have a significant amount of work to do to fully understand this outcome and its impact on the overall program. Our disappointment is no doubt shared by physicians and transplant patients, who must today contend with CMV disease.”
The primary endpoint of this Phase 3 study was the incidence of CMV disease, confirmed by an independent endpoint committee, within 6 months post-transplant. The incidence of CMV disease within 6 months was 4.4 percent for maribavir compared to 4.8 percent for placebo (P=0.79). The first of four key secondary endpoints was the rate of initiation of anti-CMV treatment within 6 months, which was 37.9 percent for maribavir compared to 40.5 percent for placebo (P=0.49). In addition, the incidence of graft-versus-host disease, mortality and CMV disease-free survival was comparable between the groups.
Source: ViroPharma, USA