The Institute of Medicine, a private offshoot of the National Academy of Sciences, has recommended that drug trials at prisons be resumed in cases where the experimental medications could benefit the inmates.

The proposal, reported by the New York Times on Sunday, includes measures designed to prevent the type of abuses that occurred in pharmaceutical testing on inmates in the past.

Almost all drug testing at prisions was discontinued in the 1970s following revelations of medical maltreatment during pharmaceutical trials. However, the latest proposal recommends the resumption of testing in those cases where experimental medications could help the participants. Such research has the potential to benefit not only the prisoners, but also the general population, the advisers note.

Testing a wide range of pharmaceutical products on inmates was common until the early 1970s, when horrific practices involving testing both inside and outside of the prison environment began to surface.

Perhaps the most notorious example of research abuse was the 40-year "Tuskegee Study of Untreated Syphilis in the Negro Male" that began in the 1930s. In 1972, it was revealed that the U.S. Public Health Service in Tuskegee, Ala., had diagnosed 400 poor black sharecroppers with syphilis but never told them of their illness or provided any treatment for it -- even after a cure was discovered. Instead, researchers used the men as human guinea pigs to study the progress of the disease. They all eventually died from syphilis.

Not long thereafter, a number of scandals at the Holmesburg State Prison in Philadelphia came to light. It was learned, among other things, that the US Army had funded tests on 320 inmates to determine the effectiveness of seven mind-altering drugs. The researchers' objective was to establish a minimum effective dose for each drug that could result in disabling 50 percent of any given population.

Also at Holmesburg, 70 volunteer prisoners participated in tests of dioxin, the chemical contaminant in the highly toxic Agent Orange used during the Vietnam war. Lesions that the men developed were left untreated for up to seven months. The subjects were not told that they would be studied later for the development of cancer.

In another Army-funded study, Holmesburg inmates were subjected to skin-blistering chemicals to determine how the skin "hardens" to protect itself from toxic chemical assaults. The information thus gained was expected to have both offensive and defensive military applications.

After the Holmesburg revelations, pharmaceutical testing in prisons came to virtual standstill. Advocates of resuming testing believe that it could be done in a manner that would prevent any such practices in the future.

Critics question whether prisoners who are already receiving substandard healthcare make good candidates for clinical drug trials. They also point out the inherent isolation of prison inmates and the ease with which abuses occurred and were kept secret in the past. Financial motives, rather than the desire to benefit humanity, might easily take over, they suggest.

But the potential benefits outweight the risks, proponents counter. The demand for human participants in clinical trials has grown tremendously in the past 10 years, while the US prison population has also soared. HIV and hepatitis are much more prevalent among prison inmates than in the general population, making prisons potentially fertile ground for testing treatments for those diseases.

They also argue that watchdog measures could be adopted to guard against the kind of abuses that occurred in the past. All studies should be conducted under independent review, for example, the report suggests.

The Institute of Medicine recommends five broad actions to provide prisoners involved in research:

1. expand the definition of "prisoner";
2. ensure universally and consistently applied standards of protection;
3. shift from a category-based to a risk-benefit approach to research review;
4. update the ethical framework to include collaborative responsibility; and
5. enhance systematic oversight of research involving prisoners.