FDA Approves Cidofovir for AIDS-Related Retinitis
FDA has approved cidofovir (trade name Vistide), for treating AIDS-associated retinitis. The following can be used to answer questions:
Cidofovir was approved as an intravenous treatment for AIDS-related CMV retinitis, a potentially severe eye infection that can lead to blindness.
Approval of cidofovir was based on two studies involving a total of 148 patients. One study showed that in patients treated immediately with cidofovir, the disease progressed less rapidly than in patients for whom therapy was delayed. A second study showed cidofovir to be effective in patients with relapsing CMV retinitis who had received other CMV therapy previously.
Cidofovir offers an alternative dosing regimen to other therapies, which are administered daily. Cidofovir is administered once weekly for the first two weeks of treatment and once every two weeks thereafter.
Renal toxicity, the most significant side effect of cidofovir, can be reduced by administering another drug, probenecid, and by supplemental saline hydration on days when Cidofovir for AIDS-Related Retinitis treatment is given. Additional reported adverse events include decreased white blood cells, weakness, nausea, diarrhea and decreased intraocular pressure (low pressure within the eye).
Although concern has been raised by studies in rats that have shown cidofovir to be carcinogenic, particularly in female rats, cancers similar to those seen in rats have not been observed in human clinical studies to date.
Cidofovir is manufactured and marketed by Gilead Sciences Inc. of Foster City, Calif.