Merck & Co has posted a 5% rise in net income for the second quarter to $1.77 billion, or $0.82 per share, while revenues dipped 1% to $6.1 billion as sales of the controversial cholesterol drugs Vytorin and Zetia fell sharply.

Revenues from Vytorin (ezetimibe plus simvastatin) and Zetia (ezetimibe), sold through a joint venture with Schering-Plough, were down 9% to $1.2 billion. Zetia sales reached $560 million, a decrease of 3%, and Vytorin was down 14% to $592 million, hit by results of the ENHANCE trial, which showed Vytorin was no more effective at slowing the progression of atherosclerosis than simvastatin (the now genericised Zocor) alone.

Vytorin continues to cast a shadow over Merck, what with the publication of the SEAS study (see related story). The company said it is currently assessing the impact of the results “and therefore at this time is not providing 2008 equity income guidance”. Chief executive Richard Clark said “we are moving quickly to fully assess the potential implications of the data” before an earnings forecast can be given.

Back to the results and Merck’s biggest seller continues to be the asthma drug Singulair (montelukast), the number one prescribed respiratory drug in the USA, though sales slipped 1% to $1.1 billion. Revenues from the anti-hypertensives, Cozaar (losartan) and Hyzaar (losartan plus hydrochlorothiazide), were up 11% at $941 million, while sales of the osteoporosis drug Fosamax (alendronate) slumped 48% to $411 million, following the loss of patent protection in the USA in February.

However Merck’s new drugs are on the up, with diabetes drug Januvia (sitagliptin) generating $334 million for the quarter, compared with $144 million in the same quarter in 2007, while Janumet (sitagliptin plus metformin) brought in $72 million. Sales of the cervical cancer vaccine Gardasil were down 9% to $326 million, while the rotavirus jab RotaTeq climbed 49% to $178 million. Turnover from the recently-launched HIV drug Isentress (raltegravir) reached $77 million.

Mr Clark said the firm had had a reasonably healthy quarter, “driving efficiencies in many parts of the business". He added that “although some results didn't meet our expectations, we are taking action to address our challenges, and remain committed to regaining leadership in the pharmaceutical industry”.

The results were slightly better than analyst forecasts but Merck shares were down 6.2% to $35.33 as the news of the SEAS study filtered through.