(dailyRx News) "One of the biggest challenges in treating GAD [generalized anxiety disorder] patients is finding a treatment that is not only effective, but also one that patients will be able to tolerate for the long term," said Philip Ninan, M.D., professor of Psychiatry and Behavioral Sciences and director of the Mood and Anxiety Disorders Program at Emory University School of Medicine. "Lexapro is a first-line treatment option, which has proven to be effective with a favorable side effect profile."
All three studies that support the indication approval were randomized, double-blind, eight weeks in duration and placebo-controlled. The studies involved approximately 850 patients, 18 to 80 years of age, diagnosed with GAD. Patients in the Lexapro arm were administered a fixed dose of 10 mg per day for the first four weeks and then flexibly dosed to a maximum of 20 mg per day. The Hamilton Anxiety Scale (HAMA) total score was the primary efficacy variable, and secondary efficacy measures included changes in HAMA psychic anxiety subscale and Clinical Global Impressions (CGI) scores.
In each of the three studies, Lexapro 10 to 20 mg per day significantly improved GAD symptoms in patients compared to placebo as measured by change from baseline in HAMA score. By-visit analyses of data pooled across the three studies revealed significantly greater improvement in the Lexapro group beginning at week one or two and continuing through week eight for all primary and secondary efficacy variables.
Further analysis of one of the three placebo-controlled studies showed that Lexapro-treated patients experienced a significant improvement in quality of life compared to patients treated with placebo as measured by the Quality of Life (QOL) scale. Sixty-eight percent of Lexapro-treated patients in the study demonstrated a significant response rate as compared to 41 percent of placebo-treated patients. In addition, more than twice as many patients in the Lexapro 10 to 20 mg per day group were in remission at week eight than in the placebo group, 36 and 16 percent, respectively.
Lexapro was well tolerated in the pooled analysis of the three studies, with eight percent of patients discontinuing treatment due to adverse events compared to four percent of patients in the placebo group. The most commonly reported adverse events in the Lexapro group versus placebo were nausea (18.2 percent versus 7.5 percent), ejaculation disorder (14.3 percent versus 1.5 percent), insomnia (11.9 percent versus 5.6 percent), fatigue (7.7 percent vs. 2.1 percent), decreased libido (6.8 percent versus 2.1 percent) and anorgasmia (5.7 percent versus 0.4 percent).
Anxiety disorders are the most common mental illness in the U.S., affecting 19.1 million adults, and cost the U.S. more than $42 billion a year. The prevalence of generalized anxiety disorder is estimated to be 4 million or 2.8 percent of the U.S. population. It affects women twice as often as men. According to The Diagnostic and Statistical Manual of Mental Disorders, the essential feature of GAD is excessive anxiety and worry (apprehensive expectations) about everyday events or activities for a period of six months or more. This constant worry affects daily functioning and can cause physical symptoms. For a diagnosis to be made, worry must be present more days than not for at least six months. GAD frequently co-occurs with mood disorders, including depression. Additionally, up to 80 percent of people suffering from depression also experience symptoms of anxiety.
Lexapro is a selective serotonin reuptake inhibitor (SSRI) and is prescribed for more than 4 million patients in the U.S.
Lexapro was approved by the U.S. Food and Drug Administration (FDA) in August 2002 for both the initial and maintenance treatment of major depressive disorder. Lexapro is available as tablets and as an oral solution.
As with all SSRIs, Lexapro should not be taken with monoamine oxidase inhibitors (MAOI). For more information about Lexapro, visit www.lexapro.com.
Charles E. Triano