Medtronic, Boston issue paclitaxel data in rebuff to safety worries
- Leading manufacturers of paclitaxel-coated balloons and stents to treat peripheral artery disease (PAD), facing stepped-up FDA scrutiny of the devices, on Tuesday offered a new round of post-market study data to support the safety and effectiveness of their products in presentations at the VIVA conference in Las Vegas.
- Medtronic reported four-year data from the IN.PACT global study of its Admiral drug-coated balloon that showed freedom from all causes of death was 83.5%, a result the company said reflected a “solid safety profile” in a challenging patient population.
- Boston Scientific said there was no difference in all-cause death between its Ranger drug-coated balloon and standard percutaneous angioplasty in the first group of patients to complete a 12-month study followup. Cook Medical said an evaluation of its Zilver drug-eluting stent showed no increase in long-term all-cause mortality at five years.
Since the publication of a meta-analysis last December raised the specter of higher mortality in patients two years after being treated for PAD with paclitaxel-coated balloons and stents, companies making the devices have stood by their products. The meta-analysis, which appeared in the Journal of the American Heart Association, prompted FDA to begin its own research into the issue and to caution physicians to choose alternative treatments in the meantime. Sales of the devices have slumped.
An FDA advisory panel in July called for product labeling to carry a warning of the potential long-term mortality risk and for further study of the devices’ safety. Panelists recommended the devices remain on the market based on a clear near-term benefit to patients but struggled to evaluate the safety of the devices due to incomplete data.
In August, FDA announced it was working with device makers to update labels and urged physicians to consider the mortality signal in making treatment decisions. Five companies, Medtronic, Cook Medical, Boston Scientific, BD and Philips, were approved for label changes in September through PMA supplements. FDA also is looking to raise patient awareness by including the risk information in informed consent documents for clinical trials.
Medtronic said the IN.PACT data presented at the VIVA meeting underscores the long-term durability and safety of the Admiral balloon in PAD patients. The four-year data from the full study cohort indicating 83.5% survival is “comparable to what would be expected” in the complex, real-world patient population, Medtronic said. Freedom from clinically driven repeat procedures was 73.4%. Of the patients enrolled, 18% had in-stent restenosis, 35.5% had occluded lesions, 39.9% had diabetes and 68.7% had calcified lesions.
Boston Scientific presented a one-year interim analysis of its Ranger drug-coated balloon and two-year results from the Imperial trial of its Eluvia drug-eluting vascular stent. In the one-year analysis, all-cause mortality for the Ranger device arm was 2.3%, compared with 2.5% in patients treated with standard angioplasty. Patients treated with Ranger had a lower rate of repeat procedures at 6%, compared with 17.9% for the angioplasty group.
In the Imperial study comparing Eluvia to Cook Medical’s Zilver PTX stent, Eluvia demonstrated an all-cause mortality rate of 7.1% at two years, which Boston Scientific characterized as low, compared with 8.3% for patients treated with Zilver, which Boston Scientific said was within the expected range for symptomatic PAD. The rate of repeat procedures at two years was 12.7% for Eluvia and 20.1% for Zilver.
Separately, Cook Medical said a review of clinical trial data for its Zilver PTX peripheral arterial stent found patients assigned to the device group had more risk factors than a control group treated with angioplasty despite the study’s randomized design. Yet five-year results from the study demonstrated no increase in long-term mortality for the paclitaxel-eluting stent.
In its August communication, FDA said patients at high risk for restenosis and repeat interventions may still have a favorable risk-benefit profile for a paclitaxel-coated device, but alternative treatments may be the better option for many patients. Doctors should take into account patients’ concerns and preferences when considering treatment with drug-coated devices, the agency said.