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 (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.