WASHINGTON--Final approval by the National Cancer Institute of the largest ever melanoma vaccine trial is near, John M. Kirkwood, MD, of the University of Pittsburgh, said at the American Association for Cancer Research (AACR) meeting. "I think before the summer is through, we should see this trial initiated," added Dr. Kirkwood, principal investigator for the study.
The trial of the novel therapeutic vaccine will involve 842 adult melanoma patients enrolled by more than 100 medical centers in the United States and perhaps Canada. The randomized, double-blind study will compare the vaccine with interferon alfa-2b(Drug information on interferon alfa-2b) (Intron A), as adjuvant therapy to prevent relapse in high-risk patients after standard treatment.
The phase III trial follows a pilot study by researchers at Memorial Sloan-Ket-tering Cancer Center, initiated in 1987, in which a small group of melanoma patients receiving the vaccine had a 70% lower risk of recurrence than controls after 6 to 7 years of follow-up.
"The eligibility for this trial is identical to the trials conducted with the interferons over the past decade," Dr. Kirkwood said. Specifically, patients must have a diagnosis of a deep melanoma, greater than 4 mm in depth, or some lymph node involvement. All will undergo surgery, and this must occur within 56 days of their entry into the trial.
Patients in the vaccine arm will receive treatments for 96 weeks, given weekly for a series, then stretched out to three-monthly over the last year, Dr. Kirkwood said. Those patients randomized to the interferon arm will receive daily interferon injections for 4 weeks, then three times weekly for 48 weeks.
Work so far shows that the vaccine produces "very few side effects, other than the types you see with immunization-- local swelling and redness at the site of injection," said Alan N. Houghton, MD, of Sloan-Kettering, at a press briefing.
The trial's clear purpose is to reduce melanoma relapse and death. People whose melanomas go 4 mm or more in depth run a 50% chance of recurrence within 2 to 5 years without adjuvant treatment. The risk rises to 80% with regional node involvement. "So we are targeting patients who have a 50% to 80% relapse risk for this therapy," Dr. Kirkwood said.