Sponsors of trials for drugs to prevent cytomegalovirus (CMV) infection in transplantation should use incidence of disease within 6 to 12 months post-transplantation as their primary endpoint, according to new draft guidance from the FDA.

The guidance distinguishes between CMV prophylaxis trials in patients who have undergone solid organ transplantation (SOT) and hematopoietic stem cell transplantation (HSCT). In the case of SOT patients, the recommended primary endpoint is a clinical endpoint of both CMV syndrome and tissue-invasive CMV disease at 6 or 12 months post-transplantation, depending on the duration of prophylaxis.

For HSCT patients, the recommended primary endpoint is incidence of infection or disease within 6 months post-transplantation.

In enrolling patients in prophylaxis trials, sponsors should ensure that patients have no detectable CMV infection post-transplantation within five days before the beginning of therapy.