Takeda Pharmaceutical has reported positive data from the Phase II clinical trial of its antiviral drug candidate maribavir (TAK-620) in cytomegalovirus (CMV) infection following hematopoietic cell or solid organ transplant.

Maribavir acts on a specific protein of the virus, UL97 protein kinase, to potentially inhibit viral DNA replication and encapsidation. The mechanism is also expected to prevent viral capsids from escaping the nucleus of infected cells.

The randomised, open-label Phase II trial compared the safety and tolerability of 400mg, 800mg and 1,200mg maribavir to 900mg valganciclovir in 159 adult patients over 12 weeks.

The primary efficacy endpoint of the trial was the proportion of responsive participants having undetectable plasma CMV DNA.

Data showed that 62% of patients on Takeda’s drug experienced a treatment effect within three weeks of therapy compared to 56% of those who received valganciclovir.

At six weeks, the response rates were observed to be 79% versus 67%.

Based on the findings, Takeda said that maribavir showed antiviral activity against CMV infection and led to a decrease in actively multiplying virus in the blood, after hematopoietic cell or solid organ transplant.

According to safety and tolerability data, 67% of subjects across maribavir arms had at least one treatment-emergent adverse event (TEAE), compared to 22% on valganciclovir.

Takeda Pharmaceutical Rare Diseases therapeutic area unit head Daniel Curran said: “Based on these results, we are evaluating maribavir for the treatment of post-transplant CMV infection in two global Phase III trials.

“The continued development of maribavir reflects the progress of our late-stage rare disease pipeline and our commitment to delivering innovative medicines for patients who have diseases like CMV where there are significant unmet needs.”

Enrolment is ongoing for the two Phase III trials of the drug to treat CMV infection in transplant patients.