Feb. 11, 2000 (Washington) -- The FDA has launched an investigation into a gene therapy experiment that may have exposed about two dozen children with cancer to HIV or hepatitis C. A spokesman for the agency tells WebMD that initial findings from the investigation should be available within two weeks.
Researchers at St. Jude Children's Research Hospital in Memphis and at Baylor College of Medicine in Houston were studying a "tumor vaccine" for an aggressive brain cancer called neuroblastoma. A series of tests done on the vaccine after it had been administered indicated that it was contaminated with the viruses that cause AIDS and hepatitis C. Even though these tests often generate false positive results and subsequent studies turned up negative, it was decided to halt the experiment until the FDA could do a more definitive analysis.
One of the lead researchers in the project denies suggestions that she improperly delayed telling the patients and their families of the potential problem. "To ... say, 'We want to notify you that you may have exposed your child to HIV by being on this trial, but we don't really know what this means, we don't really know if it's real, we'll get back to you,' I think is cruel," Laura Bowman, MD, of St. Jude, tells WebMD. The pediatric oncologist says that, in terms of informing the families, "it wasn't a question of 'if' -- it was a question of when and what to tell them." Bowman stopped the experiment Jan. 5.
Ethicists familiar with this kind of research say the episode casts a new cloud over the already troubled field of gene therapy.
Although researchers learned in December that the treatment could be contaminated, the FDA was unaware of the incident until last week, according to the agency official. The scientists didn't start notifying families about the situation until Thursday, when news reports were imminent.
"If they knew, and they only reported to the FDA, then that system is broken, broken, broken. That's not good," Arthur Caplan, PhD, a medical ethicist at the University of Pennsylvania, tells WebMD. This latest revelation comes after the gene therapy program at the University of Pennsylvania was suspended last month following the death of an 18-year-old being treated for a rare liver disorder. It was the first patient death directly attributable to a gene treatment. But the National Institutes of Health (NIH) has since gotten word of hundreds of previously unreported adverse event reports from gene experiments.
Bowman became concerned when she discovered that two of her patients had received a vaccine that might have been improperly manufactured from a master batch of cells not intended for that purpose. After locating and testing the master cells, she discovered in late December that they were weakly positive for HIV and hepatitis C.
All those in the program were near death before they enrolled. Of Bowman's group of 20 patients, there are only six survivors.
At Baylor, six children have received a similar treatment. In a statement, the medical center acknowledges it used material originally obtained from St. Jude to create its version of the gene treatment, but says the studies were conducted independently. Furthermore, Baylor says its vaccine has been thoroughly retested. "There have been no adverse events attributable to the vaccine," according to the statement.
Caplan says he's heard many gene therapists say problems like these won't make a lot of difference in the long run. "They're loony. ... The whole field has a big shadow across it," says Caplan.
Le Roy Walters, PhD, was the chairman of the Recombinant DNA Advisory Committee to NIH from 1993 to 1996. The blue-ribbon panel oversees gene therapy experiments. Walters tells WebMD that public support for such research depends on the perception of honesty and openness.
"I think the contract has been breached by some researchers and by some companies who haven't been leveling with patients, or haven't been reporting adverse events in a timely and public way," says Walters, director of the Kennedy Institute of Ethics at Georgetown University.
Both Walters and Caplan believe the current machinery in place governing research ethics needs an overhaul, either in the form of a new safety agency or at least more funding and greater political clout.