Influence of the response to induction therapy on the rate of progression of cytomegalovirus retinitis in AIDS patients on intravitreal maintenance therapy.

In order to assess whether complete inactivation of retinitis at the end of induction therapy leads to delayed progression during maintenance therapy with weekly intravitreal ganciclovir, the time to the first progression to retinitis was evaluated in 27 AIDS patients (34 eyes) with stable cytomegalovirus retinitis. Data were censored before the introduction of protease inhibitors. Overall, retinitis progressed in 22 of 34 eyes in a median time of 12 weeks (mean +/- SD, 33 +/- 9 weeks). However, retinitis progressed in 15 of 19 eyes in which only partial inactivation was achieved following induction therapy (median time, 10 weeks; mean +/- SD, 17 +/- 4 weeks) but in only 7 of 15 eyes when complete inactivation was obtained (median time, 59 weeks; mean +/- SD, 56 +/- 19 weeks) (P= 0.02). There were no differences between the groups in CD4+ cell counts, drugs, route of induction treatment, or length of induction therapy. Induction therapy should be prolonged until complete inactivation of retinitis is obtained, since achieving only a partial response appears to be a factor in earlier progression when patients are switched to maintenance therapy with intravitreal ganciclovir.