One government project that infected black men in Tuskegee, Ala., continued up until 1972 when an Associated Press story on the project caused public outrage.
In 1932, the Public Health Service, working with the Tuskegee Institute, began a study to record the natural history of syphilis in hopes of justifying treatment programs for blacks.
The study initially involved 600 black men -- 399 with syphilis, 201 who did not have the disease. The study was conducted without the benefit of patients' informed consent.
Like the Guatemalans under experimentation, they never received any treatment to cure their illness.
"Some people ask if what went on in Guatemala could go on today, and I say I don't think so," said Arthur Caplan, director of the Center for Bioethics at the University of Pennsylvania. "I don't think the pharmaceutical companies are running around giving people diseases or operating in prisons or mental asylums."
But today, drug companies hoping to speed up their Phase 3 clinical trials and get Food and Drug Administration (FDA) approval go to developing countries to find an abundance of poor patients will to try new drugs.
"Giving people a fatal disease is the worst thing you can do," according to Caplan, who said ethical questions are also raised when "we give poor people medicine for a disease they might have, and leave and sell [the drugs] in the U.S."
He said there are also no internationally enforceable standards for such research. "The world doesn't have any rules," said Caplan.
About a decade ago when the human genome was being mapped, companies were excited about exploring new drug options, and private funding expanded.
"We began to see big money come from pharma, intended to sell in the developing world but trying it out in poor nations because it could be done cheaply and faster. They face less vigorous regulatory oversight," he said.
The key to protection is informed consent. If a patient is in a placebo group and not getting the drug, they need to know that, he said.
"If they have no education and they are bedazzled to see a doctor for the first time, they may not be listening," said Caplan. "Informed consent at its best is dubious in poor countries."
Existing treatment that works on a disease should never be held back, he said. "If you come to test a diabetes drug among poor people in India and given them a placebo and not insulin, you are exploiting them, especially if you are going to sell the drug only in Europe and Canada and they get to use it for a while and then you leave."
Drugs should also be made available once the study concludes, according to Caplan.
"And if the country is so corrupt the drugs get stolen on the black market, we should commit building a water treatment plant or a clinic or make a road," he said.
And those who don't think about where their drugs are tested should think twice, he said.
"It's the same phenomenon: 'I can get really cheap clothes made by sweat shop in labor in China. I am not asking how it's made, I just like the low price,'" said Caplan. "The stance we take toward the poor is they matter less."
Prisoners, like those infected with syphilis in Guatemala are often poorly education and "easily coerced," said Caplan.
Meanwhile, Guatemala's Vice President Rafael Espada said his government would make a formal apology to his people because local doctors had also been involved in the U.S.-funded program.
President Obama has also apologized to Guatemalan President Alvaro Colom. A final report is due in December.