Merck & Co's second-quarter earnings have fallen  11.4% as a result of acquisition and restructuring charges, but revenues have edged up 1.3%, aided by the diabetes drugs Januvia and Janumet.

Net income came in at $1.79 billion, while turnover reached $12.31 billion, though that would have represented a 5% rise, excluding foreign exchange. Pharmaceutical sales were up 2% to $10.56 billion and Merck’s best-selling treatment was once again the asthma/allergic rhinitis drug Singulair (montelukast).

The drug rose 6% to $1.43 billion, ahead of going off-patent in the USA in August and in major European markets in February. The company expects "a significant and rapid reduction in sales thereafter", although Singulair will retain marketing exclusivity in Japan until 2016.

The most eye-catching performance came from Januvia (sitagliptin) which generated $1.06 billion, up 36%, while Janumet (sitagliptin plus metformin) brought in $411 million, a leap of 28%. Turnover from the HIV drug Isentress (raltegravir) reached $398 million, up 18%, while sales of the cervical cancer vaccine Gardasil increased 17% to $324 million.

Sales of the cholesterol drugs Vytorin (ezetimibe plus simvastatin) and Zetia (ezetimibe) reached $445 million and $632 million, down 3% and up 7% respectively. Revenues from the antihypertensives Cozaar (losartan) and Hyzaar (losartan plus hydrochlorothiazide) fell 17% to $337 million, due to generic competition.

The anti-inflammatory Remicade (infliximab), the Johnson & Johnson drug which Merck sells outside the USA, contributed $518 million, down 38%, as a result of the change in marketing rights agreed with J&J for the drug and its follow-up Simponi (golimumab). Merck's new hepatitis C treatment Victrelis (boceprevir) had sales of $126 million.

Chief executive Kenneth Frazier (pictured) said Merck delivered strong operational performance in the quarter, saying that  "we're seeing significant progress in the pipeline this year". He added that the firm expects six major filings over the next 18 months, "including suvorexant for insomnia and odanacatib for osteoporosis".