Design of clinical trials for drug combinations: Cytomegalovirus retinitis - foscarnet and ganciclovir. The CMV retinitis retreatment trial

The Cytomegalovirus Retinitis Retreatment Trial was a multicenter clinical trial designed to evaluate three treatments for the treatment of relapsed CMV retinitis; (1) foscarnet; (2) 'high-dose' ganciclovir, and (3) combination foscarnet and ganciclovir. Two hundred seventy-nine patients were enrolled and randomly assigned to one of these three regimens. Patients were followed monthly for 6 months and every 3 months thereafter. Outcomes of interest included: (1) mortality; (2) retinitis progression; (3) change in retinal area affected by CMV; (4) loss of visual field; (5) loss of visual acuity; (6) quality of life; and (7) treatment side effects.