Low dose 50 mg Pristiq, a new antidepressant drug that Wyeth Pharmaceuticals is working to get FDA approval, has been shown to significantly reduce symptoms of depression, according to the company today.
The data come from two Phase 3 clinical studies of Pristiq, a serotonin-norepinephrine reuptake inhibitor. SNRIs are part of the antidepressant drug family. The company presented the data today at a medical meeting in Florida.
The two studies evaluated the effectiveness and safety of Pristiq for treatment of major depressive disorder at fixed doses of 50 milligrams per day and 100 milligrams per day.
In both studies, the response rates of patients taking the 50 mg dosage was associated with a significant reduction in symptoms compared with placebo, Wyeth said.
The 100 mg dose showed a statistically significant improvement versus placebo in one of the studies, Wyeth said. However, this dose did not show statistically significant results when compared to placebo in the other study. In addition, more than twice as many patients taking the 100 mg pills dropped out of the trials due to side effects than those taking placebos.
Major depressive disorder, also known as clinical depression, is diagnosed when five or more symptoms of depression are present for at least two weeks, including feelings of sadness, hopelessness or worthlessness.
In January 2007, the U.S. Food and Drug Administration (FDA) gave conditional approval of Pristiq as a treatment for depression. In August 2007, the company submitted the results of these two additional phase 3 studies. Part of the conditional approval was because of concerns about quality control issues at a Wyeth manufacturing plant in Puerto Rico. Wyeth says those problems have been corrected.
FDA action on the application is expected during the first quarter of 2008.
Source: Wyeth and wire sources