Wyeth has received an approvable letter for its Effexor (venlafaxine) follow-up as a treatment for the symptoms of menopause. The Food and Drug Administration knocked back Pristiq (desvenlafaxine), requesting additional information prior to making its final decision.

While there was no official word from Wyeth on the news by the time PharmaTimes World News went to press, most analysts seem to anticipate the product will eventually secure a green light in the USA. The company has scheduled a conference call for today to discuss the news.

Earlier this year, the FDA said Wyeth must sort out quality control issues at its manufacturing plant before receiving approval for Pristiq in its primary indication of depression. It told the US giant that it will also have to take on “several post-marketing commitments,” including submission of long-term relapse prevention, low dose and pediatric studies, and must provide “additional clarity” around its product education plan for physicians and patients.

Wyeth is believed to be near to submitting its response to this January approvable letter and - if Pristiq reaches the market for both menopause and depression - the compound is expected to achieve more than $1 billion in sales, which will compensate for the loss of earnings once the extended-release version of Effexor faces generic competition in 2010.