A week after issuing its earnings and sales forecasts for 2008, Merck & Co has used its annual investor meeting to give an update on the seven drug candidates in its late-stage pipeline.

In the firm’s Phase III portfolio, cholesterol drugs are taking pride of place. Merck expects to hear in 2008 from the US Food and Drug Administration about its New Drug Application for Cordaptive (extended-release niacin/laropiprant) formerly known as MK-0524A, which lowers ‘bad’ low-density lipoprotein cholesterol and triglyceride levels, and also increased cardioprotective ‘good’ high-density lipoprotein cholesterol levels.

As for MK-0524B (extended-release niacin/laropiprant simvastatin), an NDA is expected to be filed next year, but the drug that has created most interest is MK-0859 (anacetrapib), an inhibitor of the cholesterol ester transfer protein that has shown promise in lipid management by raising HDL-C and reducing LDL-C) without raising blood pressure.

Sequenced Phase III programme for anacetrapib
Peter Kim, president of Merck Research Laboratories, noted that the safety and tolerability profile of anacetrapib was comparable to placebo in studies conducted to date, adding that in 2008, “we plan to initiate a sequenced Phase III programme to obtain additional clinical experience in patients before initiating an outcomes study." Investor interest in anacetrapib stems from the high-profile failure of Pfizer’s drug torcetrapib last year, which works through the same mechanism as Merck’s candidate.

Phase III trials of torcetrapib were terminated just over a year ago because monitors were worried about the imbalance of mortality and cardiovascular events but Merck believes that its product’s safety profile is much better than Pfizer’s failed drug.

Back to the pipeline and Merck anticipates filing an NDA in 2008 for MK-0364 (taranabant), a highly selective cannabinoid-1 receptor inverse agonist that in early clinical studies has demonstrated weight loss. The drug belongs to the same family as Sanofi-Aventis’ Acomplia (rimonabant) which was given short shrift by the FDA early this year.

One of the agency’s advisory committees rejected Acomplia saying that the benefits of the drug do not outweigh the risk of psychiatric adverse effects, including suicide and seizures. Merck notes that psychiatric problems, including depression, have also been seen in patients taking taranabant but the firm feels the issue is one of dosage.

The other five Phase III drugs are MK-0974, an investigational oral calcitonin gene-related peptide receptor antagonist for the treatment of migraine which should be filed in 2009, as should MK-7418, (rolofylline) for the treatment of acute heart failure. In 2010, NDAs are scheduled for MK-8669 (deforolimus), a novel mammalian target of rapamycin for cancer, and Hepsilav, a hepatitis B vaccine, while Merck plans a 2012 NDA for osteoporosis compound MK-0822 (odanacatib).

The company plans to make two supplemental filings with the FDA in 2008, one for Gardasil, a vaccine for the prevention of cervical cancer, for an expanded indication for adult women aged up to 45, and another for HIV drug Isentress (raltegravir), for use in treatment-naive patients.

The pipeline was described by Deutsche Bank analyst Barbara Ryan among others as impressive and promising sales of new products such as Gardasil and diabetes drugs Januvia (sitagliptin) suggest that Merck is very well-placed for future growth.