The date by which the FDA is expected to decide is July 23, still two months away, but Pristiq is an important drug for Wyeth, which is essentially repackaging Effexor XR, the depression pill, to treat the hot flashes associated with menopause.

Given ongoing questions about the drug’s propensity to raise blood pressure and the FDA’s recent reaction to safety issues, Prudential Equity’s Tim Anderson speculates that the FDA will approve Pristiq, but may include warnings that could limit sales. He makes these points:

- Pristiq is in a class of drugs that reliably raise blood pressure, and in one large trial recently disclosed five patients on Pristiq had cardiovascular events events compared with none on placebo. Could this be worrisome given that Pristiq is intended for a patient population whose risk of heart disease is already elevated due to older age and post-menopausal status?

- In all situations, a drug’s safety needs to be balanced against its effficacy. On efficacy, Pristiq appears to be only modestly better than placebo. Results from one trial recently released showed Pristiq’s efficacy to be no better than placebo.

- How will the FDA come out on Pristiq’s risk-benefit calculation? We think the drug will get approved, but wonder to what degree the label could reflect cardiovascular safety concerns.IIn the current FDA environment all possible outcomes need to be anticipated.

Anderson also makes this interesting observation: “Pristiq for vasomotor symptoms will be reviewed by a different FDA division of FDA than will Pristiq for depression. Sometimes, different arms of the FDA view the risk-benefit ration of a given molecule differently. One need only look to Lilly’s Cymbalta and Yentreve for a relevant examplee.

Cymbalta was approved for depression, but the same molecule, under the different brand name of Yentreve, was essentially turned down as a treatment for urinary incontinence, due to the FDA’s concern that potential safety issues of Cymbalta outweighed the drug’s potential efficacy in this particular indication. Cymbalta is mechanistically the same as Pristiq - both are serotonin norepinephrine reuptake inhibitors, or SNRIs.”

[tags]Pristiq, Tim Anderson, Wyeth[/tags]