Use of heroin-blocking agents on addicted ex-convicts "will cure their desire for heroin within three months," a Harvard Medical School professor said yesterday.

Vernon Patch, associate professor of Psychiatry and head of the drug rehabilitation center at Boston City Hospital, said he plans to test the drug naltrexone hydrochloride on paroled addicts from Deer Island Prison. "It will help them protect themselves against heroin," he said.

"Inmates leave prison with drug hunger and seek drugs upon release, so they just return to their old lives. The blocking agents prevent them from getting a high on heroin," Patch said.

Patch added that the drug is being tested at McClain Hospital and the Washingtonian Center, both in Boston, but under different control conditions. Patch would be the first to use the drug on former inmates.

Experimentation

William J. Curran, professor of Legal Medicine at the Medical School, said. "I am not categorically against the use of inmates in experimentation, in or out of prison." Curran is a member of the Committee of Psychiatry at the Medical School, one of two groups which gives Harvard's sanction to this type of experimentation.