Boston Scientific (NYSE:BSX) shares took a hit yesterday after a Centers for Medicare & Medicaid Services proposal that would limit coverage for the Watchman anti-stroke device. Investors also likely reacted to a pair of Class II recalls from the FDA, sending BSX shares down -4.2% to $18.01 apiece yesterday.
Watchman, a transcatheter implant designed to seal off the left atrial appendage to prevent the formation of blood clots that could cause stroke, was approved by the FDA in March and asked for a CMS coverage decision in May. The federal health insurer proposed to limit coverage for Watchman to patients in approved clinical trials who can’t take warfarin, an anti-coagulant drug.
Earlier this week, Boston Scientific touted data from a real-world registry showing a 2.8% rate of serious adverse events at 7 days. The company reported that 92.7% of patients were free from serious adverse events at 1 month post procedure. A total of 61.8% of patients were deemed contraindicated for oral anticoagulants in the study, which is slated to follow patients for 2 years.
“At this time, there is insufficient evidence to determine that percutaneous LAA closure using an implanted device improves health outcomes compared to non-invasive standard medical therapies for Medicare beneficiaries with [non-valvular atrial fibrillation]. Therefore, LAA closure using an implanted device should only be considered in patients with NVAF with a high stroke risk and a contraindication to anticoagulation (e.g. history of a significant bleeding event such as intracranial or life-threatening bleeding, the source of which cannot be eliminated) in a clinical trial or comparative study,” the agency said Nov. 10.
The CMS proposal is open for public comments through Dec. 10. The agency is slated to issue its final decision by February next year.
The pressure on BSX shares was augmented yesterday when the FDA issued a pair of Class II recalls for the Watchman device and a sheath dilator used in its implantation. The FDA said the company sent a field correction letter in August issuing “further guidance regarding the correct us of the hemostatis valve in order to avoid cross-threading and to securely seal the valve, minimizing the potential for undesirable blood leakage.”
“Cross-threading of the hemostasis valve may occur if it is tightened with the dilator in place, possibly preventing subsequent sealing of the valve when desired,” according to the federal safety watchdog, which applies the Class II label to devices that could cause “temporary or medically reversible adverse health consequences or where the probability of serious adverse health consequences is remote.”