Foscarnet and ganciclovir in the treatment of cytomegalovirus retinitis.

ABSTRACT

Induction regimens of foscarnet and ganciclovir are highly effective in arresting cytomegalovirus (CMV) retinitis in patients with AIDS. Chronic maintenance therapy is nonetheless required to forestall progression of disease following induction. In open studies of these two agents in AIDS patients with CMV retinitis at dosages similar to those currently recommended, median times to retinitis progression during maintenance therapy of as long as greater than 100 days have been observed. In a randomized comparative trial of immediate and delayed foscarnet treatment utilizing rigorously defined end points, the mean times to retinitis progression were 13.3 weeks among patients receiving immediate foscarnet therapy and 3.2 weeks among those receiving no treatment. In a similar trial of ganciclovir, the mean times to progression were 68.5 days among patients receiving immediate treatment and 22.9 days among those receiving no treatment. Experience in a number of studies not designed to assess mortality has suggested that specific antiviral treatment for CMV retinitis is associated with prolongation of survival. One retrospective analysis of survival patterns in patients treated with ganciclovir has suggested a significant effect of this agent on survival; another analysis has shown no association between anti-CMV therapy and survival, with the relative hazard of death among patients receiving foscarnet therapy being equivalent to that among patients receiving ganciclovir therapy. In the one randomized study comparing the mortality of patients receiving initial treatment with either foscarnet or ganciclovir, foscarnet-treated patients had a median survival of 12.6 months compared with 8.5 months for ganciclovir-treated patients.(ABSTRACT TRUNCATED AT 250 WORDS)