Forest Laboratories of the USA has posted a 28% leap in third-quarter net income to $250.3 million, or $0.78 per share, helped by strong contributions from the antidepressant Lexapro and the Alzheimer’s disease drug Namenda.

Turnover for the quarter was up 18% to just over $893 million, with sales of Lexapro (escitalopram) climbing 14% to $545.9 million, while Namenda (memantine) enjoyed a 40% increase to $173.9 million.

The figures beat analysts’ estimates and Forest upped its full-year earnings forecast to $2.79-$2.84 from a prior guidance of $2.60-$2.65 per share. The new estimate excludes the impact of the one-time R&D charge related to the recent acquisition of Cerexa of approximately $494 million, or approximately $1.54 per share. That charge will be recorded in the fourth quarter.

Speaking of the Cerexa buy, chief executive Howard Solomon said that the deal “provides us with major opportunities in an entirely new therapeutic area, the hospital injectable anti-infective market” and noted that Cerexa's most advanced product, ceftaroline, a next-generation, broad-spectrum, hospital-based cephalosporin antibiotic which will shortly be commencing Phase III studies.

More worrying for Forest is that patent protection for both Lexapro and Namenda runs out around 2012 and analysts are a little concerned about the state of its pipeline. In October, Forest and partner Replidyne were hit with a non-approvable letter from the US Food and Drug Administration for faropenem medoxomil, their antibiotic for acute bacterial sinusitis, community-acquired pneumonia, chronic bronchitis and adult skin infections and Forest said that it will reveal its plans for the compound later in the year.

As for the antihypertensive nebivolol, Forest is looking to file an application with the FDA by late March or early April for the drug after the agency asked for more information in October. Despite the positive results, Forest’s stock slipped 0.7% but Danish partner Lundbeck, which licenses both Lexapro and Namenda, saw its shares rise on the Copenhagen Stock Exchange