By Lisa Rapaport
June 21 (Bloomberg) -- U.S. regulators delayed a request by Johnson & Johnson to expand use of its top-selling Risperdal to include schizophrenia and bipolar disorder in adolescents.
The Food and Drug Administration didn't request new studies on the treatment in a letter to the company, New Brunswick, New Jersey-based J&J said in a statement today. J&J said it would work with the agency to complete prescribing information on the drug, which is already approved for use in children with autism and adults with schizophrenia and bipolar disorder.
Use of antipsychotic drugs for younger patients has risen sharply in recent years, prompting concern among some doctors and parents about side effects including weight gain and diabetes. Risperdal, which generated $4.2 billion last year, is the second such drug delayed by U.S. regulators for teen use. Eli Lilly & Co.'s Zyprexa was held up in April.
``The FDA is giving approvable letters for everything under the sun these days, and in this case they are particularly gun shy because this is about kids and there are known side effects,'' said Ira Loss, an analyst at the Washington research firm Washington Analytics, in a telephone interview today.
The FDA normally issues what is known as an approvable letter to inform companies that more information is needed before a drug can be marketed in the U.S.
The shares of Johnson & Johnson fell 4 cents to $62 at 1:02 p.m. in New York Stock Exchange composite trading. The stock had declined 6 percent this year before today.
About 1 in 100 people have schizophrenia, which causes hallucinations and distorted thinking, and a third of them develop it in adolescence.
Prescriptions of the drugs for teenagers are currently written mostly by psychiatrists as ``off-label'' or unapproved uses. Once a drug is cleared in the U.S., doctors aren't required to limit uses to those on the prescribing label.
Sales for Risperdal, which faces generic competition next year, rose 18 percent in 2006. Overall, prescriptions of antipsychotics for patients age 20 or younger rose sixfold from 1993 to 2002, from 201,000 to 1.22 million, according to a study published last year in the Archives of the Journal of the American Medical Association.
``There's no gold standard for treating schizophrenia in teens, and the first company to get FDA approval for this will have an edge in the very crowded market,'' said Les Funtleyder, an analyst at Miller Tabak & Co. in New York, in an interview prior to the J&J announcement.
FDA approval of antipsychotics for teenagers would encourage pediatricians and primary-care physicians to prescribe the drugs as well, said Mark Olfson, lead author of the study and a professor at Columbia University in New York. Use of Prozac and other antidepressants for younger patients soared after the FDA cleared those drugs for children.
``These antipsychotics will follow the same path as Prozac,'' Olfson said. ``The FDA label gives physicians outside psychiatry some reassurance and confidence in prescribing these medications.''
Bristol-Myers asked the FDA to approve its antipsychotic drug Abilify for schizophrenia in teenagers on June 5. Abilify sales surged 41 percent to $1.3 billion last year, helped by studies showing the pill caused less weight gain than competitors.
``There is a very likely possibility that the FDA approval of a teenage indication will provide a false sense of security,'' psychiatrist Stefan Kruszewski, of Harrisburg, Pennsylvania, wrote the FDA in a letter opposing clearance of the drugs. ``Approval would function as the means by which aggressive pharmaceutical marketing could easily persuade more practitioners to prescribe more potent medications.''