Clinical Alert

October 17, 1991

Clinical Alert To Physicians And Others Who Treat Patients With AIDS

Dear Colleague:

This letter is to inform you of findings from the Foscarnet-Ganciclovir Cytomegalovirus Retinitis Trial. This randomized, multicenter clinical trial is supported by the National Eye Institute, a component of the National Institutes of Health (NIH). It was conducted in collaboration with the AIDS Clinical Trials Group sponsored by the National Institute of Allergy and Infectious Diseases at NIH.

The trial was designed to evaluate the relative efficacy and safety of foscarnet and ganciclovir for the initial treatment of cytomegalovirus (CMV) retinitis in patients with AIDS. On October 7, the trial's independent Policy and Data Monitoring Board recommended suspending the protocol because the data indicated that patients treated with foscarnet lived on average four months longer than those treated with ganciclovir. The median survival for those treated with foscarnet was approximately 12 months, compared to eight months for those treated with ganciclovir. The difference in survival could not be explained by variations in disease severity at the time patients entered the study or to other chance factors.

Foscarnet and ganciclovir appeared to be equally effective in halting the progression of CMV retinitis and preserving vision. While a survival benefit for foscarnet was seen in most patients, in the group of patients who entered the study with a predicted creatinine clearance <1.2 ml/min/kg, a survival benefit was seen for ganciclovir (see the attached treatment administration protocol).

Within the trial, anti-retroviral therapy [zidovudine (AZT), ddI, and ddC] was used according to best medical judgment. The difference in mortality between the foscarnet-treated patients and the ganciclovir-treated patients could not be fully explained by differential anti-retroviral use. However, the trial was not designed to study possible interactions between anti-CMV and anti-HIV treatments. Therefore, such an explanation cannot be ruled out.

These findings suggest that foscarnet may be the preferable initial treatment for CMV retinitis. A possible exception is the subgroup of patients with decreased renal function (predicted creatinine clearance <1.2 ml/min/kg) who appeared to do better on ganciclovir.

The complete findings from this study will be published soon. This announcement is being sent in advance of journal publication to physicians likely to treat patients with AIDS who have CMV retinitis. A press conference will be held on October 21 at the National Institutes of Health.

Sincerely,


Carl Kupfer, M.D.
Director
National Eye Institute

Douglas Jabs, M.D.
Study Chairman
Studies of the Ocular Complications of AIDS
Associate Professor of Ophthalmology and Medicine
Johns Hopkins University School of Medicine