Wyeth Pharmaceuticals, a division of Wyeth, announced that the company has received an approvable letter from the US Food and Drug Administration (FDA) for Pristiq (desvenlafaxine succinate), a serotonin-norepinephrine reuptake inhibitor (SNRI) studied as a treatment for adult patients with major depressive disorder (MDD). The letter was received January 22, a company release stated.

"The approvable letter is in line with Wyeth's expectations and we remain on track with our plans for Pristiq," says Joseph Mahady, president, Wyeth Pharmaceuticals - North America and Global Businesses. "We are working toward resolution of all outstanding issues at our manufacturing site in Guayama, Puerto Rico and have already made significant progress in meeting previously established commitments."

According to the approvable letter, FDA approval of Pristiq is subject to several conditions, including: A satisfactory FDA inspection of the Company's Guayama, Puerto Rico facility, which is where Pristiq will be manufactured; Several post-marketing commitments, including submission of long-term relapse prevention, low dose and paediatric studies; Additional clarity around the company's product education plan for physicians and patients; Confirmation by the FDA of the acceptability of the proprietary name, Pristiq.

As the company has already communicated, launch timing for the MDD indication is predicated on three elements - final FDA approval for Pristiq as a treatment for adult patients with MDD, the results of ongoing MDD studies at lower dosage levels, and the progress of FDA review of Wyeth's separate New Drug Application (NDA) for vasomotor symptoms (VMS) associated with menopause. Importantly, while the approvable letter requires some post-marketing commitments, the FDA does not require that any additional clinical studies be submitted prior to the approval of Pristiq.

"Given the importance of Pristiq, we are committed to ensuring the most complete profile and product information is available to physicians and patients at the time of this product's launch," Mahady says.

Pristiq is an SNRI studied as a potential treatment for adult men and women with MDD. Wyeth submitted a NDA for MDD on December 22, 2005. The Company has also filed a NDA for VMS associated with menopause and expects an FDA action letter in the second quarter of 2007. If approved, Pristiq will be the first and only non-hormonal medicine for the treatment of VMS associated with menopause. Wyeth is a leader in both neuroscience and women's health care.

Wyeth discovered and developed the first SNRI approved by the FDA, which is currently the most widely used antidepressant in the world. Pristiq represents Wyeth's latest efforts and continued commitment to developing therapies to help improve the lives of patients suffering from mental health disorders.

According to a large depression trial funded by the National Institute of Mental Health, only 28 per cent of patients with depression achieved remission with initial antidepressant treatment. This leaves a large percentage of patients still suffering from depression. Clearly, additional medicines are needed for treating MDD.