|The Watchman device--Courtesy of Boston Scientific|
Unlike most medical technology, the only FDA-approved transcatheter implant to ward off stroke competes not with other devices but with blood-thinning drugs. As a result, the adoption of Boston Scientific's ($BSX) Watchman is being handled with great care by the medical community and will be influenced greatly by the numerous studies on its paradigm-shifting approach to limiting the harm caused by atrial fibrillation.
A paper just published in the Journal of the American College of Cardiology was supportive of the cost-effectiveness of the implant as compared to the blood thinner warfarin and four other recently approved oral anticoagulants.
Boston Scientific said in an email blast that the Watchman achieved cost-effectiveness relative to warfarin after 7 years, and relative to new oral anticoagulants (NOACs) at 16 years. The study found that Watchman became more effective and less costly than warfarin after 10 years and NOACs at 5 years. The study measured cost-effectiveness using quality-adjusted life years.
Dr. Valentine Fuster of The Mount Sinai Hospital gave a nice overview of the pluses and minuses in his audio commentary, located within the paper's abstract. The arguments for and against the device reflect the drug/device divide, a topic which will become increasingly prominent if and when more devices start competing with drugs in other therapeutic areas.
Procedural complications, like bleeding of the pericardial sac, are a risk, and led to delayed approval at the hands of the FDA. Fuster noted that the risks decline predictably with operator experience.
On the other hand, the Watchman eliminates the problems noncompliance and nonadherence that plague medications. "By its very nature, the Watchman device is not subject to patient adherence issues, since once implanted, the device provides lifelong stroke prophylaxis without the risk of complications associated with blood thinners," said Dr. Vivek Reddy, the director of cardiac arrhythmia services at Mount Sinai, in a statement. "This is crucial both in improving patient outcomes by reducing disabling strokes, as well as reducing health care costs."
Reddy was co-principal investigator for U.S. clinical trials of the Watchman, and has served as a consultant for Boston Scientific.
In his commentary, Fuster said the study does not settle the issue of the cost-effectiveness of the Watchman compared to drugs, but should provide the device with positive momentum, perhaps driving increased adoption.
Fuster said a limitation of study is its backwards-looking nature. Data on clinical outcomes to measure cost effectiveness were gathered from the device's clinical trials and a meta-analysis of blood thinner studies.
More studies are also needed to compare the Watchman to the NOACs that aim to replace warfarin as the standard of care on the drug side. Those drugs are not as well-studied as the much older warfarin. Boston Scientific said Watchman patients experienced fewer disabling strokes than warfarin or NOAC patients.
The paper studied the cost-effectiveness on 70-year-old patients over a 20-year time horizon using a Markov economic model. It attempted to take the perspective of the federal Centers for Medicare & Medicaid Services.
CMS' actual perspective on Watchman reimbursement is being closely monitored by Boston Scientific. Under its Coverage with Evidence Development policy, CMS recently proposed reimbursement only for nonvalvular atrial fibrillation patients who are not on warfarin and enrolled in a national registry.
Coverage with Evidence Decision is a common reimbursement policy prescription, but the contraindication for patients on the blood thinning drug warfarin was unpleasant news for Boston Scientific, and contradicts FDA's indication for use.
The company is in discussions with CMS, which will issue a final decision as soon as early next year, following the conclusion of the 60-day comment period. Much will depend on whether the contradiction is a strict one, and covers all but those patients who are medically ineligible for warfarin, or whether CMS also agrees to reimburse patients found noncompliant or nonadherent to the drug's instructions for use.
St. Jude Medical ($STJ) is watching the situation closely, as it attempts to decide whether to submit its CE marked analogue to the Watchman for FDA approval.
Boston Scientific recently launched a second-generation version of the Watchman in Europe, where devices (and upgrades to prior devices) are routinely approved faster than in the U.S.
- read the release
- here's the paper abstract and audio commentary