“Statins,” which include medications such as simvastatin (Zocor) and lovastatin (Mevacor), are FDA-approved medications that decrease cholesterol levels. Recently it has been recognized that, in addition to decreasing cholesterol levels, statins also affect the immune system. This finding has led to the hope that statins may have beneficial effects on immune system diseases such as multiple sclerosis (MS).

Over the past several years, statins have undergone investigation in MS. The studies in this area have led to a sort of drama in the MS research and clinical community. For people with MS (as well as health professionals), the details of this drama provide instructive information about interpreting medical studies. Also, this research provides helpful thoughts about how people with MS should view statins now and how statins may play a role in MS therapy in the future.

For use as a medical therapy, statins have an interesting position. They are already FDA-approved and are thus available through pharmacies. As a result, these medications may, if thought appropriate, be prescribed by physicians for their FDA-approved use as cholesterol-lowering drugs or for “off-label” use as drugs for MS or other conditions.

Act I
Several years ago, studies of statins produced promising results. Laboratory studies showed that statins have anti-inflammatory effects and decrease the severity of disease in the animal model of MS—these studies were suggested that statins may have beneficial effects in MS. Consequently, a study was conducted in 30 people with MS. This study found that Zocor treatment decreased the number and size of lesions on MRIs by about 40 percent. These results were not definitive, however, because the animal model of MS is not an ideal model for the disease and the clinical study was small and did not include a placebo-treated group.

On the basis of these limited animal and human studies, some physicians and other health professionals actually recommended and prescribed statins to treat people with MS.

Act II
The next wave of information about statins and MS was presented at the annual meeting of the American Academy of Neurology (AAN) in the spring of 2007. At this meeting, concerns were raised about statins. Specifically, in test-tube experiments it was reported that statins could produce effects that might actually decrease the effectiveness of interferons, which include Avonex, Betaseron, and Rebif. In addition, in a small clinical study of people with MS, there was an indication that statins did indeed decrease the effectiveness of interferons. Importantly, test-tube experiments, like studies of the animal model, are not perfect indicators of what will happen in the actual disease. In addition, the clinical study was small.

With this new information, some health professionals raised concerns over the use of statins in people with MS, especially in those who were treated with interferons. Some even suggested that people with MS should not be treated with interferons if they take statins or might take statins in the future.

Act III
In the fall of 2007, encouraging information about statins and MS was presented at the annual meeting of the European Committee for Treatment and Research in MS (ECTRIMS). Scientific studies indicated that statins may work effectively with interferons. Furthermore, in three different clinical studies, preliminary findings were that statins did not inhibit the effects of interferons. Once again, the scientific experiments are not absolutely reliable models of what happens in the human body, and the reports of the clinical studies are preliminary.

This information about statins and MS was encouraging but, in light of previous studies, it was also confusing. Many health professionals are not sure what role statins have on MS or on interferon treatment.

Act IV and Beyond
There are several ongoing clinical studies of statins in people with MS. These studies involve using statins alone or in combination with other MS medications, such as interferons. The results of these studies should become available over the next one to two years.

Everybody’s Talking, Nobody Knows
So what does all of this mean? There are several lessons that can be learned from this saga. It is important to respect the process by which medical therapies are developed. Typically, initial studies of an experimental therapy are done in test-tube type experiments. If those experiments indicate possible beneficial effects for a specific disease, then the experimental therapy is tested in an animal model of that disease. If the animal model studies are promising, then clinical studies are done to test for safety and effectiveness in humans. The ultimate clinical study in humans is known as a “Phase III” study, which is a large and rigorous study. If positive results are obtained in a Phase III study, then the FDA may approve the drug for use.

For all diseases—especially complex diseases such as MS—the effect of an experimental therapy is not truly known until it has been shown to be safe and effective in Phase III studies. Dramatic examples of the importance of this concept have occurred with several MS experimental drugs. These drugs initially produced promising results in test-tube experiments and in the animal model of MS but were subsequently found to be harmful to people with MS in large and rigorous clinical trials.

In the case of statins and other experimental therapies, it is important to wait for results of large and well-conducted studies. If therapies are used before the research studies are done, then the therapies could actually be harmful for the disease or could inhibit the effects of other medications. Several more “Acts” of the statin story will need to play out before it is appropriate to use these drugs on a widespread basis in people with MS. In particular, we need to see results of large and rigorous statin studies in people with MS. In the meantime, if you have MS and are considering statin use, you should discuss the use of this medication with your physician.