Esperion Therapeutics (NASDAQ:ESPR) has been on a roller coaster ride in the days leading up to Tuesday's press release updating its clinical trial of a new therapeutic protein that is supposed to unclog arteries.

Esperion's drug candidate, ETC-216, is a protein variant discovered in an Italian family who have very low rates of heart disease. The protein actually seems to reverse atherosclerosis, the clogging of arteries. If successful, this biopharmaceutical would be a good complement to statin therapies that lower overall cholesterol levels. Statin drugs include blockbusters like Lipitor, Zocor, and Pravachol. In fact, Roger Newton, Ph.D., the CEO of Esperion was the co-discoverer and developer of Lipitor for Pfizer (NYSE:PFE).

After progressing through the Phase I safety trial with no problems, Esperion embarked on its Phase II. This trial was designed to determine if ETC-216 would actually reduce coronary artery plaque size in patients with partially blocked arteries.

During a conference call on Tuesday, the company reported that there was a 4.2% reduction in plaque volume over five weeks, with only five injections of the drug. By comparison, three years of statin therapy showed 0.4% reduction in plaque volume. One negative aspect of the study was the lack of enough patients to acquire enough data to compare the therapy to the standard medical treatment. However, the study was not designed to do this comparison.

While these results are promising, the drug probably is only going to be able to be delivered by injection for acute coronary events, which might not be as lucrative a market as the long-term use of statin pills. The drug will also need to undergo Phase III testing with more patients to see if the results hold up.

Interestingly enough, the results of this study were published in the Journal of the American Medical Association(JAMA) and shipped out last Thursday, with a major sell-off happening on Monday, after many subscribers had received their copies. Everyone who did not have a copy of the journal article was required to wait until the conference call on Tuesday to hear the news. It seems that not everyone is agreeable to the spirit of disclosing news to all of the public at the same time, unfortunately.

David Nierengarten, Ph.D., works with a biotechnology venture capital fund. He often contributes to Fool.com and is an active member of the TMF community as DavidMN. He owns shares of Esperion. He appreciates your comments at davidnierengarten@mac.com and on the Biotechnology discussion board.