The US Medicaid programme is reportedly considering a cut in its $5.5 billion annual spend on schizophrenia drugs, according to Industry reports, after the Government-funded CATIE study revealed that the cheaper generic perphenazine was just as effective as newer, substantially more expensive, antipsychotics [[20/09/05f]].

CATIE compared the effectiveness and side effects of the generic and four newer antipsychotics: Eli Lilly’s Zyprexa (olanzapine), Pfizer’s Geodon (ziprasidone), Johnson & Johnson’s Risperdal (risperidone) and AstraZeneca’s Seroquel (quetiapine), and found little difference in their efficacies compared to perphenazine. Only Lilly’s Zyprexa, which notched up sales of a staggering $4.4 billion in 2004 (32% of company sales), fared better than the other agents in terms of discontinuation of therapy rates. Patients taking the agent were less likely to require hospitalization for a psychotic relapse and tended to stay on the medication longer than those receiving other treatments.

The study’s findings have potentially very significant implications, as the 40-year-old perphenazine costs less than $1.50 a day, while its branded successors can be priced at up to 10 times as much.

Results from CATIE could well have a devastating impact on the newer medicines’ performances as, according to Deven Herrick, quoted by Bloomberg, a lot of Medicaid programmes will use the study to review the medicines. He concluded: “It's probably wise to start with a cheaper drug and move your way up from there.'' Any switch in coverage will likely take a sizable chunk out of the drugs’ revenues, which collectively total over $9 billion a year.

But health experts are warning that the one-size-fits-all approach does not apply to the treatment of schizophrenia, which is usually somewhat complex. Doctors should be allowed access to the broadest range of therapies possible, as no one antipsychotic is best suited for all patients, further underscoring the need for multiple treatment options.