How dangerous are pharmaceutical clinical trials that are conducted overseas?

The question was in the news repeatedly this year as Pfizer, the world’s biggest drugmaker, tussled with the Nigerian state of Kano over a 1996 clinical trial of its Trovan antibiotic. The testing took place during a meningitis epidemic, and Pfizer was held responsible for 11 deaths and dozens of injuries.

For months, Pfizer executives were on the defensive, especially after a federal appeals panel ruled that dozens of Nigerians could sue the drugmaker in a U.S. court. So this past July, a $79 million settlement was reached, with most of the fund to be used to establish health care initiatives there and to settle claims. Bad publicity aside, the payout was a far cry from the $2 billion that Kano officials had sought.

But the damage was done—the long-running dispute highlighted sobering questions about whether the pharmaceutical industry follows international law and properly offers informed consent to patients, which has become a flash point in a growing debate over the ethics of running clinical trials in other countries.

“This whole topic is a big concern,” says Vera Sharav, an industry critic who heads the nonprofit Alliance for Human Research Protection. “There may be exploitation of enrolled patients. You may also get drugs that are based on data that was obtained improperly and then approved here by the FDA. And that’s because there’s insufficient FDA oversight of these trials.”

The issue is gaining attention because more trials are run in foreign countries. Nearly one-third—or 157 out of 509—clinical trials registered on a federally run website are being conducted overseas, according to an article earlier this year in the New England Journal of Medicine. Meanwhile, more than half of all trial sites—13,521 out of 24,206—are outside the U.S., with many located in Eastern Europe and Russia, where oversight standards are evolving.