By Maggie Fox

WASHINGTON (Reuters) - New drugs to treat

One study published in the American Journal of Psychiatry found it was important to ask whether a patient quit taking his first drug because it was not working, or because it was causing side-effects.

A second found that if patients can stick to a treatment, any treatment, they end up doing better in society than patients who stop.

However, both of the U.S. government-funded studies show there really is no good drug for treating schizophrenia, a mental disorder that affects about 1 percent of the population globally and 3.2 million Americans.

"We find again that the treatments we are using don't measure up all that well," Dr. Jeffrey Lieberman of Columbia University in New York, who led the study, told reporters in a telephone briefing.

The researchers used data from the $42.6 million CATIE (Clinical Antipsychotic Trials in Intervention Effectiveness) trial, paid for by the National Institute of Mental Health, to find if three of the newer schizophrenia drugs worked better than older drugs, or better than one another.

They included Johnson & Johnson's risperidone, sold under the brand name Risperdal; olanzapine, made by Eli Lilly and Co. under the brand name Zyprexa; and quetiapine, made by AstraZeneca under the brand name Seroquel.

They looked at 114 patients who had quit taking the older drug perphenazine and who had been randomly assigned to take one of the newer drugs.

NEWER, NOT BETTER

Most quit taking the new drugs, too.

Patients taking Seroquel did not quit for 10 months on average, those on Zyprexa lasted seven months and those taking Risperdal quit on average after four months.

Perphenazine can cause unpleasant side-effects including a movement disorder characterized by grimacing, eye blinking and other involuntary motions. But patients complained that the new drugs often made them sleepy, confused and caused weight gain.

Zyprexa was the drug that worked best if patients had stopped taking perphenazine because it did not control their schizophrenia symptoms, said Dr. T. Scott Stroup of the University of North Carolina.

"It confirms a clinical hunch that if a person doesn't do well on a drug, they do better if you try something really different," Stroup said.

"We hope we can help doctors choose these drugs sooner and promote recovery."

The second study, led by Dr. Marvin Swartz of Duke University in North Carolina, found that patients who stuck to one drug for a year or more had modest improvements in social, interpersonal and community living skills.

Their study of 455 patients taking part in CATIE found it did not matter which drug they took.

"Patients were more able to function in the community if they were able to stick to treatment, especially the most impaired, although those were the most likely to drop out," Swartz said.

"We concluded from this that ... we need better drugs and better access to social services so that these patients can learn to function and to work in the community better," Swartz said.

More than 90 percent of prescriptions for antipsychotics are for such second-generation drugs, accounting for $10 billion in U.S. sales.