Merck & Co has been awarded marketing approval for Liptruzet, a new combination cholesterol treatment based on Zetia and generic atorvastatin.
The new once-daily drug is a line extension to Merck’s Vytorin product, which combines the active ingredient in Zetia (ezetimibe) with the company’s own off-patent simvastatin, and has previously been turned down by the FDA on two occasions.
Merck is upfront about the capabilities of the new therapy, indicating in its press release that while the combination is more effective than atorvastatin alone in reducing cholesterol levels Liptruzet does not improve on atorvastatin’s efficacy in reducing cardiovascular morbidity and mortality.
The new product effectively places Merck in the position of promoting the combination therapy for its ability to tackle a biomarker – the proportion of patients who can meet LDL cholesterol targets – rather than a clinical endpoint.
Sales of Zetia as a monotherapy reached $2.57bn last year, with Vytorin adding another $1.75bn. Liptruzet’s potential is hard to gauge as it will depend on the reception given the drug by cardiologists, but analysts have suggested it is likely to be a smaller product with sales below $500m a year.
One of the main problems for the new product will be the perception that Merck dragged its heels publishing the data from a key clinical trial – ENHANCE – which found that Vytorin did no better than simvastatin monotherapy in reducing the development of arterial plaques and threw the entire concept of LDL levels as a surrogate market for drug development into debate.
Earlier this year, Merck agreed to pay $688m to settle investor claims that it delayed disclosure of the ENHANCE results.
In fact, many cardiologists were not expecting a decision on Liptruzet until the publication of results from the IMPROVE-IT study, which will look at the clinical impact of Vytorin versus simvastatin monotherapy on hard clinical endpoints in patients with acute coronary syndrome (ACS). The data is not due for release until 2014.
Eminent cardiologist Steve Nissen of the Cleveland Clinic told Forbes that the approval was “extremely surprising and disturbing”, given the lack of clinical efficacy data and controversy about the benefits of ezetimibe.