Autism drug fails latest clinical trial
Parents of children with autism received disheartening news last week with the report that the hormone secretin, an alternative treatment for the disorder, did not significantly improve children’s symptoms in a clinical trial.
The study results, released Monday by the Massachusetts-based pharmaceutical company Repligen Corp., are the latest disappointments surrounding the controversial and expensive therapy. Some parents have credited injections of the gut hormone -- produced in the small intestine -- with marked improvements in their children’s behavior; some have driven themselves into debt to ensure a steady supply, seeking the drug overseas when supplies in the United States dried up.
But a string of studies has failed to confirm such anecdotal successes in carefully controlled trials, and last week’s study was the largest and most definitive yet.
“There are no surprises here,” said Dr. Adrian Sandler, medical director of the Olson Huff Center at Mission Children’s Hospital in Asheville, N.C., coauthor of an earlier trial showing no effects on autism of a single secretin injection. “The results ... show in my view that there really is no role for secretin in the treatment of autism.”
Some believers in the therapy are still holding out hope. Bernard Rimland, director of the Autism Research Institute in San Diego and an advocate of the therapy, said that the trial was flawed.
“There is no doubt whatsoever that a significant number of kids respond to secretin,” he said.
Autism is a serious developmental disorder in which children often appear cut off from the world around them, uninterested in social interactions. Precise symptoms vary widely. For instance, some children never develop language, while others learn to talk or read at precociously young ages. In recent years, reported rates of the disorder have increased significantly in California and elsewhere, for reasons that scientists have yet to explain.
Although behavioral therapies and certain medications can help, experts say that there is no known cure for the disorder, and some parents have sought out alternative therapies.
Secretin, a digestive hormone that doctors use to diagnose disorders of the pancreas, entered the stage in the late 1990s after a New Hampshire couple, Victoria and Gary Beck, reported that their son Parker’s autism symptoms improved significantly after injection with secretin for gut disturbances he was having. Many parents have since tried the treatment, and although many have seen no benefit, some believe that it has helped their children’s behavioral symptoms.
The study reported last week enrolled 132 children, ages 2 to 4, all with moderate to severe symptoms of the disorder, at 15 clinical sites. The children were given six intravenous injections of either secretin or a placebo over a period of 18 weeks, and their behaviors were assessed by psychologists and parents. Nobody knew which children were receiving the hormone.
Although no changes were observed in the secretin group as a whole, Repligen (which sponsored the trial and supplied the synthetic human secretin that was used in it) noted that higher-functioning children did show statistically significant improvements. The significance of that finding is unclear.
Walter Herlihy, president and chief executive of Repligen and the father of two autistic children, said that any future studies on secretin and autism would depend on a thorough review of the data.
It is still possible to think the therapy might work, at least for certain children, said Portia Iversen, co-founder and scientific liaison for the Los Angeles-based nonprofit group Cure Autism Now. Autism, she said, has many varieties of symptoms and levels of severity, and maybe a subgroup of autistic children could benefit from the hormone, if only the right children could be identified.
“Until we get a better grip on this disorder in terms of the major subtypes it’s going to be very hard to get a grip on what has occurred in a major clinical trial,” she said.
Meanwhile, some parents who feel the drug has helped their children said they do not intend to stop treatments, whatever it costs.
“If we had to sell our home, we would do it,” said 54-year-old Jan Henry of Chattanooga, Tenn.
She said she and her husband ran the gamut of alternative therapies before trying secretin injections in 1998 on their severely autistic son Andrew, now 27. She credits the drug with helping Andrew become calmer, more sociable and able to speak in phrases instead of single words. The family spent $10,000 during the first year of therapy and has periodically struggled to find sources of the hormone and to pay for it.
Dr. Sarah Spence, medical director of the UCLA autism clinic and an investigator in the secretin study, said she was very disappointed with the trial’s results.
“Everybody who works in autism wants there to be an effective treatment. And every time something is shown to be not effective, it’s very disheartening,” she said.
“We’re there in the front lines with parents every day. We want to be able to offer them something that has good scientific backing -- and there’s not much out there.”