Merck & Co., Inc. (MRK), Pfizer Inc. (PFE), AstraZeneca plc (ADR) (AZN) – Pick Your Poison: Overweight or High Cholesterol

Merck & Co., Inc. (NYSE:MRK)Overweight and have high cholesterol? You may have to pick one to work on at a time, according to data from the lab of John Thyfault, an associate professor of nutrition and exercise physiology at University of Missouri.

Statins work really well at lowering bad LDL cholesterol, but they can cause muscle ache in some patients. Thyfault and colleagues decided to see if cholesterol-lowering drugs would affect benefits from exercise in obese and overweight patients.

The study, published in the Journal of the American College of Cardiology, used Merck & Co., Inc. (NYSE:MRK)‘s Zocor, but it seems safe to assume that other statins — Pfizer Inc. (NYSE:PFE)‘s Lipitor and AstraZeneca plc (ADR) (NYSE:AZN)‘s Crestor — would give similar results given that statins work in the same way.

Taking Zocor didn’t affect adherence to the exercise program — both the group taking Zocor and those prescribed exercise alone went to 95% of exercise sessions over 12 weeks — but there were dramatic effects on the outcomes of the exercise.

Cardiovascular fitness, defined by the amount of oxygen consumed normalized to body weight, increased by 10% in patients prescribed exercise alone, but only by 1.5% in those who also took a statin. The researchers also found that a marker for activity of mitochondria, which turn oxygen and sugar into energy, decreased by 4.5% in the patients who took Zocor, but increased, as it should, by 13% in the group that wasn’t given the drug.

The increased fitness translated into weight loss. Over the 12 weeks, the exercise-only group lost 1.7% of their body weight on average, but the weight of the group that took Zocor increased slightly.

The study was small — just 37 subjects between the two groups — but the results were dramatic enough that they were statistically significant, meaning it was unlikely to have happened by chance alone.

The obvious solution is to lose the weight first and then start taking a statin. Changing diet and exercise should have a positive effect on cholesterol anyway.

Bristol Myers Squibb Co. (NYSE:BMY)‘s Pravachol, an older statin, has been show to have less of a negative effect on mitochondrial content than other statins. Doctors could also prescribe lower doses. In the study, a 40 mg dose was given, but Zocor’s label suggests that doctors can start as low as 10 mg.

Merck & Co., Inc. (NYSE:MRK) has another cholesterol-lowering drug Zetia, which works in a different way as statins and could be used as an alternative. Of course, Zetia doesn’t lower cholesterol all that much by itself and is mostly used as an add-on therapy to statins. It’s even co-formulated with Zocor as Vytorin and with Lipitor as Liptruzet. Beyond Zetia and statins, there are a few other cholesterol-lowering drugs, including PCSK9 inhibitors, which aren’t on the market yet.

I doubt these data will have a dramatic effect on sales of any of the drugs — and Lipitor, Zocor, and Pravachol are available as generics, so their sales are already toast — but it may spur a larger study to drive home the message that losing weight is made even harder by taking a statin.

The article Pick Your Poison: Overweight or High Cholesterol originally appeared on and is written by Brian Orelli.

Fool contributor Brian Orelli has no position in any stocks mentioned. The Motley Fool has no position in any of the stocks mentioned.

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