Abbott Laboratories, one of the biggest makers of coronary stents in the world, is halting global sales of a fully absorbable stent that was once hailed as the next big breakthrough in medical devices that open up blocked arteries.

Abbott, which acquired Minnesota's St. Jude Medical and competes for stent sales with Medtronic and Boston Scientific, announced on Friday that it is halting sales of its Absorb GT1 "bioresorbable vascular scaffold" stent as of Sept. 14 because of low sales, not safety concerns. Unlike traditional permanent metal stents, the Absorb stent breaks down inside the body over time like ­dissolving sutures.

The U.S. Food and Drug Administration told doctors in March that the agency is investigating the rate of major adverse cardiac events among Absorb patients, which appears higher compared to Abbott's traditional metal stent, Xience, after two years.

Spokespeople for Abbott said Absorb devices remain safe to use, and the decision to halt sales globally was not driven by safety concerns. Analysis of recent clinical trial results shows that the Absorb and Xience stents have "similar outcomes" when the doctor follows the latest implant guidance.

"This decision is based on commercial unsustainability," Abbott spokesman Jonathon Hamilton said in an e-mail Friday.

"Absorb is a first-generation device that took longer to implant than metallic stents. Sales volume for Absorb was low, and it cost more to make Absorb than what it sold for — making it unsustainable. We continue to work on second-generation bioresorbable technology with a smaller profile and improved deliverability to reduce implantation time."

Hamilton said Absorb accounted for less than 1 percent of the company's global stent sales.

An analysis of clinical trials, published in the medical journal the Lancet last month, documented more than 3,200 Absorb patients in randomized studies who had their devices for at least two years. Abbott said Friday that it would continue to follow patients in clinical trials per the study protocols.

A frequently-asked-questions section on Abbott's website Friday said doctors can continue to implant the Absorb stents they have in stock, but they will not be able to obtain more after next week.

Supposed to be safer

Absorbable stents like the Absorb were supposed to be safer than metallic stents, which can hold a vessel open for a time but may eventually become re-clogged.

Stent still holds promise

Boston Scientific was also in the race to develop an absorbable coronary stent, but an executive told the Star Tribune in July that the company has halted future investments in its program after watching Abbott's struggles with the Absorb. Although the technology still shows promise, Boston Scientific decided to focus its investments in other more strategic areas for now.

Abbott was more emphatic about its future work in absorbable stent technology: "We will continue work on a next generation device. First-generation products often go through iterations as experience is gained using them. Absorb is a highly innovative groundbreaking device, and we're incorporating learnings into our second-generation product," Hamilton wrote.