Wyeth yesterday reported a strong set of financial results for the first quarter of 2005, with double-digit rises in both sales and net earnings, although it also warned that demand for its top-selling product, the antidepressant Effexor (venlafaxine), is showing signs of softening.

Revenues rose 14% to $4.6 billion dollars, ahead of analysts’ estimates, while net income came in at $1.1 billion, or 80 cents a share, a hefty 44% hike on the $749 million or 55 cents achieved in same period of 2004, although the comparison is flattered by a $149 million charge in the prior quarter [[22/04/04c]].

The Effexor franchise managed a 12% rise to $868 million, but the changing dynamics of the antidepressant market, and particularly the loss of patent protection on some high-earning brands and concerns about the safety of these drugs, is slowing its momentum, according to Wyeth.

Rheumatoid arthritis treatment Enbrel (etanercept) – which Wyeth co-promotes in North America with Amgen and has exclusivity elsewhere – saw revenues leap 75% to $237 million, helped by its recent approval for psoriasis. Future growth should also come from Japan, where it was launched in late-March and is co-promoted with Takeda, said the company [[08/04/05d]]. Meanwhile, sales of pneumococcal disease vaccine Prevnar doubled to reach $391 million, although gastrointestinal drug Protonix (pantoprazole) revenues were flat at $409 million.

Continued weakness was seen in Wyeth’s hormone replacement therapy franchise, with Premarin (conjugated estrogens) sales sliding 21% to $211 million, as the safety concerns surrounding HRT continued to exert an effect.

With Effexor and Protonix losing momentum, Wyeth needs new products to plug the gap, and believes it has one in Tygacil (tigecycline), a first-in-class injectable antibiotic which has been tipped as a blockbuster. This was granted a priority, six-month review by the US Food and Drug Administration in January [[31/01/05f]].

Investors were also cheered by the news that Wyeth believes its reserves set aside for making payments in the long-running diet drug damages case [[11/04/05d]], are adequate and will not have to be increased.