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Pooled Analysis of Antidepressant Studies Demonstrated Significant Efficacy of Venlafaxine

PHILADELPHIA, Sept. 26 /PRNewswire-FirstCall/ -- Wyeth Pharmaceuticals, a division of Wyeth , presented at a major conference an analysis of patient data from studies comparing antidepressant treatments demonstrating that significantly more patients achieved remission (virtual elimination) of their depression symptoms, and resolution of both emotional and physical symptoms, when treated with EFFEXOR® (venlafaxine HCl)/EFFEXOR® XR (venlafaxine HCl) than with studied selective serotonin reuptake inhibitors (SSRIs) or placebo. The pooled analysis compared EFFEXOR/EFFEXOR XR to the SSRIs PAXIL® (paroxetine), PROZAC® (fluoxetine), ZOLOFT(r) (sertraline), LUVOX® (fluvoxamine), and CELEXA® (citalopram) and comprised the entire worldwide dataset of Wyeth-sponsored registration and post-marketing, published and unpublished, SSRI-controlled clinical studies of EFFEXOR/EFFEXOR XR to date. The analysis was presented in two poster presentations this week at the European College of Neuropsychopharmacology's (ECNP) annual meeting in Prague, Czech Republic.

The analysis was planned and the data pooled after completion of over 30 comparable, randomized, double-blind, active, drug-controlled clinical studies conducted worldwide in over 7,000 patients with major depressive disorder. Nine of these studies were also placebo-controlled. Investigators in all of the double-blinded studies randomly assigned patients to receive either EFFEXOR/EFFEXOR XR or a specific SSRI, as designated in the individual protocol.

"EFFEXOR XR is a proven serotonin-norepinephrine reuptake inhibitor (SNRI) supported by a large clinical data set obtained through studies conducted using rigorous efficacy measurements," says Dr. Norman Sussman, Clinical Associate Professor of Psychiatry and Director of Psychopharmacology Research and Consultation Services, Bellevue Hospital Center in New York City. "The results of this pooled analysis, the most comprehensive of its kind of which we are aware, show that EFFEXOR XR can play a significant role in helping patients achieve the goal of becoming virtually symptom-free." EFFEXOR XR is believed to increase levels of both serotonin and norepinephrine, two of the brain chemicals thought to be implicated in depression, generalized anxiety disorder (GAD), and social anxiety disorder (SAD).

Background on Comprehensive Pooled Analysis of 7,000 Patients

One poster describing the analysis showed that patients treated with EFFEXOR/EFFEXOR XR had significantly higher remission rates than those treated with the studied SSRIs using evaluations which included scoring seven or less on the 17-item Hamilton Rating Scale for Depression (HAM-D17) or less than 10 on the Montgomery-Asberg Depression Rating Scale (MADRS).

The second poster describing an analysis of this data, focusing on the treatment of the physical symptoms of depression, documented that treatment with EFFEXOR/EFFEXOR XR was significantly more effective than the studied SSRIs in reducing the anxiety/somatization symptoms associated with depression based upon the criteria of the anxiety/somatization factor of the HAM-D21 scale (anxiety-psychic, anxiety-somatic, somatic symptoms-GI, somatic symptoms-general, hypochondriasis, and insight). Furthermore, significantly more patients treated with EFFEXOR/EFFEXOR XR achieved resolution of the general somatic symptoms of depression. In addition to the emotional symptoms inherent in depression, such symptoms can include backache, headache, muscle aches, loss of energy, fatigue and heaviness in limbs, back and head. In these studies, 38 percent of the EFFEXOR/EFFEXOR XR group achieved resolution of the general somatic symptoms, against 32 percent of SSRI-treated patients and the 25 percent of placebo patients (p

Additional remission evaluations used in the analysis included Clinical Global Impressions-Improvement (CGI-I) and Clinical Global Impressions-Severity (CGI-S) scores, as well as compatibility of participants' age, weight, duration of illness, and baseline scores using HAM-D21, MADRS, and CGI-S.

This comprehensive pooled analysis included double-blind studies with DSM-III-R™ or DSM-IV™ major depressive disorders. Twenty-four of the studies were active-controlled, and nine were both active- and placebo-controlled. Investigators in all of the double-blinded studies randomly assigned patients to receive either EFFEXOR/EFFEXOR XR or a designated SSRI and administered comparable average doses based on the efficacy of the medications (doses ranged from 75 to 375 mg/day for EFFEXOR, 75 to 300 mg/day for EFFEXOR XR, 20 to 80 mg/day for Prozac, 20 to 40 mg/day for Paxil, 20 to 60 mg/day for Celexa, 50 to 200 mg/day for Zoloft, and 100 to 200 mg/day for Luvox).

More than 19 million Americans each year suffer from depression, which interferes with the ability to work, study, sleep, eat, and enjoy once pleasurable activities.


EFFEXOR XR is a structurally novel antidepressant chemically unrelated to any other available antidepressant. EFFEXOR XR is believed to increase levels of both serotonin and norepinephrine, two of the brain chemicals thought to be implicated in depression, GAD, and SAD.

The most common adverse events reported in EFFEXOR short-term placebo-controlled depression trials and EFFEXOR XR short-term placebo-controlled depression, generalized anxiety disorder (GAD), and/or social anxiety disorder (SAD) trials (incidence greater than or equal to 10% and greater than or equal to 2x that of placebo) were anorexia, asthenia, constipation, dizziness, dry mouth, ejaculation problems, impotence, insomnia, nausea, nervousness, somnolence, and sweating.

EFFEXOR/EFFEXOR XR is contraindicated in patients taking monoamine oxidase inhibitors (MAOIs). Treatment with venlafaxine is associated with sustained increases in blood pressure (BP) in some patients. Regular BP monitoring is recommended. Abrupt discontinuation or dose reduction has been associated with discontinuation symptoms. Patients should be counseled on possible discontinuation symptoms and monitored while discontinuing the drug; the dose should be tapered gradually; see the Dosage and Administration section of the Prescribing Information.

EFFEXOR XR was discovered and developed by Wyeth Pharmaceuticals, the pharmaceutical division of Wyeth. The product is also marketed by Wyeth Pharmaceuticals. The immediate-release formulation was approved by the FDA in 1993; the extended-release (XR) formulation was approved in 1997. These medications are available only by prescription.

Source: Wyeth Pharmaceuticals

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