|Systematic (IUPAC) name|
|Trade names||Pristiq, DESFAX|
|Licence data||US FDA:|
|Protein binding||Low (30%)|
|Metabolism||CYP3A4, (CYP2D6 is not involved)|
|Biological half-life||11 h|
|Excretion||45% excreted unchanged in urine|
|CAS Registry Number|
|Molecular mass||263.38 g/mol|
|(what is this?)|
Desvenlafaxine (brand name: Pristiq, DESFAX), also known as O-desmethylvenlafaxine, is an antidepressant of the serotonin-norepinephrine reuptake inhibitor (SNRI) class developed and marketed by Wyeth (now part of Pfizer). Desvenlafaxine is a synthetic form of the major active metabolite of venlafaxine (sold under the brand names Effexor and Efexor). It is being targeted as the first non-hormonal based treatment for menopause.
Very common (>10% incidence) adverse effects include:
- Dry mouth
Common (1-10% incidence) adverse effects include:
- Blurred vision
- Decreased appetite
- Sexual dysfunction
- Elevated cholesterol and triglycerides
- Feeling jittery
- Hot flush
- Abnormal dreams
- Urinary hesitation
Uncommon (0.1-1% incidence) adverse effects include:
Rare (<0.1% incidence) adverse effects include:
Unknown frequency adverse effects include:
Desvenlafaxine is a synthetic form of the isolated major active metabolite of venlafaxine, and is categorized as a serotonin-norepinephrine reuptake inhibitor (SNRI). When most normal metabolizers take venlafaxine, approximately 70% of the dose is metabolized into desvenlafaxine, so the effects of the two drugs are expected to be very similar. It works by blocking the "reuptake" transporters for key neurotransmitters affecting mood, thereby leaving more active neurotransmitters in the synapse. The neurotransmitters affected are serotonin (5-hydroxytryptamine) and norepinephrine (noradrenaline). It is approximately 10 times more potent at inhibiting serotonin uptake than norepinephrine uptake.
The molecule resembles hordenine with additions.
Wyeth announced on 23 January 2007 that it received an "approvable" letter from the Food and Drug Administration for desvenlafaxine. Final approval to sell the drug was contingent on a number of things, including:
- a satisfactory FDA inspection of Wyeth's Guayama, Puerto Rico facility, where the drug is to be manufactured;
- several postmarketing surveillance commitments, and follow-up studies on low-dose use, relapse, and use in children;
- clarity by Wyeth around the company's product education plan for physicians and patients;
- approval of desvenlafaxine's proprietary name, Pristiq.
The FDA approved the drug for antidepressant use in February 2008, and was to be available in US pharmacies in May 2008.
In 2008, Wyeth withdrew its application for Ellefore, the product under review for treatment of major depressive disorder in the European Union. In 2012, Pfizer received authorization in Spain to market Pristiq for such disorder under 50mg and 100mg tablets. 
In clinical trials, desvenlafaxine demonstrated a significant superiority to placebo both in changes from baseline in the HAM-D17 score and in measures of well being such as the Sheehan Disability Scale (SDS) and 5-item World Health Organization Well-Being Index (WHO-5).
- "Wyeth Receives Approvable Letter From FDA for PRISTIQ for the Treatment of Vasomotor Symptoms Associated With Menopause" (Press release). Wyeth. 2007-07-24. Retrieved 2007-07-31.
- "PRODUCT INFORMATION PRISTIQ® desvenlafaxine (as succinate)" (PDF). TGA eBusiness Services. Pfizer Australia Pty Ltd. 10 December 2012. Retrieved 8 November 2013.
- "DESVENLAFAXINE tablet, extended release [Ranbaxy Pharmaceuticals Inc.]". DailyMed. Ranbaxy Pharmaceuticals Inc. March 2013. Retrieved 9 November 2013.
- "desvenlafaxine (Rx) - Pristiq, Khedezla". Medscape Reference. WebMD. Retrieved 9 November 2013.
- Lemke, Thomas L.; Williams, David A. (2012). Foye's Principles of Medicinal Chemistry. Lippincott Williams & Wilkins. p. 609. ISBN 978-1-60913-345-0.
- Deecher, DC; Beyer, CE; Johnston, G; Bray, J; Shah, S; Abou-Gharbia, M; Andree, TH (August 2006). "Desvenlafaxine succinate: A new serotonin and norepinephrine reuptake inhibitor" (PDF). The Journal of Pharmacology and Experimental Therapeutics 318 (2): 657–665. doi:10.1124/jpet.106.103382. PMID 16675639.
- Roth, BL; Driscol, J (12 January 2011). "PDSP Ki Database". Psychoactive Drug Screening Program (PDSP). University of North Carolina at Chapel Hill and the United States National Institute of Mental Health. Retrieved 9 November 2013.
- "Wyeth Receives Approvable Letter From FDA For Pristiq (Desvenlafaxine Succinate) For The Treatment Of Major Depressive Disorder" (Press release). 2007-01-23. Retrieved 2007-04-04.
- "FDA Approves Pristiq" (Press release). Wyeth. 2008-02-29. Retrieved 2008-02-29.
- Health Canada Notice of Compliance - Pristiq. February 4, 2009, retrieved on March 9, 2009.
- Thase ME, Kornstein SG, Germain JM, Jiang Q, Guico-Pabia C, Ninan PT (March 2009). "An integrated analysis of the efficacy of desvenlafaxine compared with placebo in patients with major depressive disorder". CNS Spectr 14 (3): 144–54. PMID 19407711.
- Soares CN, Kornstein SG, Thase ME, Jiang Q, Guico-Pabia CJ (October 2009). "Assessing the efficacy of desvenlafaxine for improving functioning and well-being outcome measures in patients with major depressive disorder: a pooled analysis of 9 double-blind, placebo-controlled, 8-week clinical trials". J Clin Psychiatry 70 (10): 1365–71. doi:10.4088/JCP.09m05133blu. PMID 19906341.