Abbott initiates international ABSORB BTK clinical trial for treatment of below-the-knee critical limb ischemia

Abbott today announced the initiation of ABSORB BTK, an international clinical trial evaluating the safety and efficacy of the ABSORB™ bioresorbable vascular scaffold (BVS) for the treatment of below-the-knee (BTK) critical limb ischemia. Critical limb ischemia, a severe form of peripheral artery disease (PAD), occurs when blocked vessels impair blood flow to the lower extremities, which can eventually lead to limb amputation. ABSORB restores blood flow by opening a blocked vessel and providing support to the vessel until the device dissolves within approximately two years. The first patient was enrolled into the ABSORB BTK trial by Marc Bosiers, M.D., head of the Department of Vascular Surgery at St. Blasius Hospital in Dendermonde, Belgium.

“Patients with critical limb ischemia often progress to where they have few options beyond limb amputation, so there is a tremendous need for new therapies to prevent this outcome,” said Dierk Scheinert, M.D., Professor of Medicine, the University of Leipzig, Germany, and principal investigator of the ABSORB BTK trial. “The ABSORB device represents the next generation in revascularization therapies that may hold promise for patients with vessel disease in the lower leg. With the ABSORB BTK trial, we will test whether this novel approach – restoring blood flow with a temporary scaffold – has the potential to improve the outcomes of patients with critical limb ischemia.”

The ABSORB device is made of polylactide, a proven biocompatible material that is commonly used in medical implants such as dissolvable sutures. Because a permanent metallic implant is not left behind, naturally occurring vessel functions may be restored, which is one of the features that make this device a significant innovation. In January 2011, Abbott announced that ABSORB received CE Mark and is authorized for sale in Europe for the treatment of coronary artery disease. ABSORB currently is under development and is not available for sale in the United States.

ABSORB BTK is a prospective, single-arm, multi-center trial designed to evaluate the safety and efficacy of the ABSORB device in up to 90 patients with below-the-knee critical limb ischemia at up to 10 clinical trial sites in Europe and New Zealand. The primary endpoint is a composite of freedom from major adverse limb events (major amputation or major re-interventions) within one year or death within 30 days of the procedure.

“With the ABSORB BTK trial, we will be able to evaluate our bioresorbable drug and device technology as a potentially new therapeutic option for patients with below-the-knee critical limb ischemia,” said Charles A. Simonton, M.D., FACC, FSCAI, divisional vice president, Medical Affairs, and chief medical officer, Abbott Vascular. “Our efforts to apply this technology to the treatment of vascular diseases beyond coronary artery disease underscore our continued commitment to developing innovative products to improve vascular care for patients.”

About Critical Limb Ischemia

Critical limb ischemia is a severe form of peripheral artery disease (PAD) that is characterized by chronic pain, even at rest, as well as ulcers and gangrene (tissue death) that develop as a result of chronically poor blood flow to the lower limbs. Endovascular treatments of below-the-knee arteries, including balloon angioplasty and stenting, have emerged as effective forms of therapy. For some patients, surgical bypass procedures are performed. If left untreated, the disease can eventually lead to amputation and limb loss.

In January 2011, Abbott announced that the XIENCE PRIME™ Everolimus Eluting Coronary Stent System received CE Mark in Europe for the treatment of critical limb ischemia or severe claudication (pain) of the lower leg. In the U.S., XIENCE PRIME currently is an investigational device and not available for sale. Additional information about XIENCE PRIME is available online at www.abbottvascular.com.

About the ABSORB Clinical Trials for Coronary Artery Disease

Abbott has conducted one clinical trial called ABSORB and currently is conducting a second trial called ABSORB EXTEND to evaluate the company’s bioresorbable device for the treatment of coronary artery disease. The ABSORB trial is a prospective, non-randomized, two-stage study that enrolled 131 patients from Australia, Belgium, Denmark, France, the Netherlands, New Zealand, Poland and Switzerland. Key endpoints of the study include assessments of safety – major adverse cardiac events (MACE) and treated-site thrombosis rates – as well as an assessment of the acute performance of the device.

Results from the first stage of the ABSORB trial showed that in 30 patients, no blood clots (thromboses), no cardiac deaths out to four years and no new MACE between six months and four years were reported. Twelve-month results from the second stage showed that in 101 patients, the MACE rate was 6.9 percent and no blood clots were reported.

The ABSORB EXTEND trial is a large-scale, single-arm study that will evaluate ABSORB in patients at up to 100 centers in Europe, Asia Pacific, Canada and Latin America. The trial will enroll approximately 1,000 patients with complex coronary artery disease.

ABSORB delivers everolimus, an anti-proliferative drug. Everolimus was developed by Novartis Pharma AG and is licensed to Abbott by Novartis for use on its drug eluting vascular devices. Everolimus has been shown to inhibit treated-site neointimal growth in the coronary vessels following vascular device implantations, due to its anti-proliferative properties.

About Abbott Vascular

Abbott Vascular is a global leader in cardiac and vascular care with market-leading products and an industry-leading pipeline. Abbott Vascular offers a comprehensive cardiac and vascular devices portfolio, including products for coronary artery disease, vessel closure, endovascular disease and structural heart disease.