JAMA study: Biodegradable drug-eluting stent safer than bare-metal variety

New research suggests that a biodegradable drug-eluting stent could be safer than its bare-metal counterpart. Swiss scientists determined that the next-generation product, which releases the drug biolimus, caused fewer cardiac problems over one year compared to the older market rival.

The Journal of the American Medical Association published details of the study by Dr. Lorenz Räber and colleagues at Bern University Hospital in Bern, Switzerland. MedPage Today also offers a great round-up of the work.

As the researchers point out, controversy continues over whether drug-eluting stents are safer for heart attack patients who have had a certain kind of heart attack, compared to bare-metal stents in patients who undergo balloon angioplasty or stent placement to prop open narrowed coronary arteries. Part of the concern is that traditional drug-eluting stents can delay healing of the blood vessel and cause chronic inflammation, due to polymers used for the product. New blood clots with drug-eluting stents are also a risk, MedPage Today notes.

But the new finding suggests that biodegradable polymers might be a longer-term industry solution, as the article points out, because they still release the drug in a controlled fashion. And with the eventual elimination of the biodegradable polymer, the other side effects might be minimize or avoided entirely, the researchers explain. (Surely stent makers, like Abbott, Boston Scientific ($BSX), Biosensors, Biotronik, Medtronic ($MDT) and others are taking note.)

For the, the researchers used the biodegradable BioMatrix Flex stent, which is made by Switzerland-based Biosensors International. Previously, scientists compared the product to Johnson & Johnson/Cordis' ($JNJ) sirulimus-eluting Cypher stent, which does not break down in the body, and found it to be similar (non-inferior). For this study, they conducted a randomized, single-blinded control trial of 1,161 patients with STEMI at 11 sites in Europe and Israel between much of 2009 and early 2011. Researchers gave 575 patients the biolimus-eluting stent with biodegradable polymer, and 582 received the bare-metal stent.

What they found: Major cardiac problems at one year hit 4.3% of the patients who received the biolimus-eluting stent with the biodegradable polymer, versus 8.7% of patients who received the bare-metal stents. Death rates for both also came out about the same: 16 with the biolimus stent, and 20 with the bare metal variety, according to the study. Fewer patients with the biodegradable stent also experienced subsequent blood clots.

- read the release
- here is the JAMA abstract