Thu Jun 3, 2004
By Ben Hirschler, European Pharmaceuticals Correspondent
LONDON (Reuters) - Medicating attention disorder, already a $2.2 billion-a-year business, is about to get a lot bigger as drug companies expand the treatment from children to adults.
Traditionally associated with kids' tantrums, attention deficit hyperactivity disorder (ADHD) has been viewed as an illness which is outgrown in adolescence.
Yet up to 65 percent of children with ADHD may still exhibit symptoms into adulthood, according to some studies, making grown-ups a lucrative new market for drug manufacturers.
Eli Lilly & Co's Strattera is currently the only ADHD pill with approval from the U.S. Food and Drug Administration for use in adults. But Britain's Shire Pharmaceuticals Group expects its market-leading Adderall XR to get a green light within the next month or two.
"The adult market is three times the size of the children's market. The market is ripe and is moving in the right direction," Matthew Emmens, Shire's chief executive, told Reuters in an interview.
Much of the past three years of sales growth is, in fact, due to U.S. doctors already prescribing for adults, he added.
Some medics, however, are uncomfortable at snowballing drug use which is now spreading beyond the United States, where spending on behavioral disorders overtook the cost of antibiotics and asthma medicines for children in 2003.
In Britain, where use of medication is more recent and Novartis AG's Ritalin dominates, opinion is deeply divided about using stimulants on children and the expansion into adults.
A recent British Medical Association debate found most doctors opposed giving more medicines to children, even though British treatment rates are way below the U.S. level.
Between three and five percent of U.S. children are diagnosed with ADHD, a condition which is marked by reduced ability to concentrate, difficulty in organizing and impulsive behavior. In Britain and most of Europe, meanwhile, the rate is a fraction of one percent.So which side of the transatlantic divide has got it right?
David Coghill, senior lecturer in child and adolescent psychiatry at the University of Dundee, is convinced of the benefits of medication and is angered by suggestions that ADHD is not a proper disease.
"At least 80 percent of the risk of having ADHD depends on your genes, which is a very strong indication of a biological basis for a disorder," he said.
The strong hereditary link also suggests many parents with ADHD children may have the disorder themselves.
Others, though, are worried by growing pressure to medicate.
"Pediatricians are making quick and dirty assessments and then deciding on treatment, often under great pressure from extremely hard-pressed families," said Harvey Marcovitch of Britain's Royal College of Paediatrics and Child Health.
International studies suggested up to 50 percent of children receiving medication do not actually meet the clinical guidelines defining ADHD, he added.
Whatever the opposing views, though, all the signs are that the ADHD drug market is here to stay and set to grow.
20 PERCENT GROWTH
In the United States, which accounts for the vast majority of prescriptions, sales are increasing at around 20 percent a year and drug companies are developing new, improved treatments to exploit the new adult opening.
Lilly's Strattera is the first non-stimulant to reach the market and other companies are working hard to follow suit. In contrast to rivals, Strattera is not designated as a controlled substance, a class of drugs tightly regulated to prevent abuse.
Other firms are re-analyzing the role of existing medicines.GlaxoSmithKline, for example, is considering seeking approval to use antidepressant Wellbutrin XL in adult ADHD, as it is already given by some doctors for the condition.
The exact mechanism of action of ADHD drugs remains unclear but they appear to work by amplifying chemical signaling in the brain associated with attention. In particular, they seem to boost the activity of dopamine, a key message-carrying chemical.
For many of those dealing with ADHD at the sharp end, however, the biochemical processes are incidental.
Andrea Bilbow, a mother of an ADHD child who runs the Attention Deficit Disorder Information and Support Service in Britain, sees the issue in stark terms.
"One tablet can do more in half an hour than a therapist can do in three years," she said.
(Additional reporting by Jed Seltzer in New York)