TVT Registry Sparks Discussion on Device Evaluation, Treatment Comparisons

MIAMI BEACH, FLA.—As myriad devices are being developed, society as a whole must consider how to encourage innovation while balancing safety and efficacy and also ensuring access to care, said David R. Holmes Jr, MD, of the Mayo Clinic in Rochester, Minn., in a session devoted to clinical trial design and interpretation at TCT 2012.

Using the Transcatheter Valve Therapy (TVT) Registry as an example, Holmes explained how professional society-sponsored registries can further those goals.

The TVT Registry was launched by the Society of Thoracic Surgeons and the American College of Cardiology in December 2011, a month after the Sapien valve (Edwards Lifesciences) was approved by the FDA. A national registry of all TAVR procedures, it links surgical, interventional and government databases and “is meant to work in concert with industry partners,” Holmes said. “Finally, it will create a research engine for future studies.” The generic platform, he explained, provides infrastructure for projects ranging from premarket research to postmarket surveillance; it enables studies on comparative effectiveness, appropriateness of care and other issues relevant to real-world practice.

But this is “not going to be cheap or easy,” he stressed, noting hurdles such as resource cost and shifting priorities. “Maybe the dose of naiveté was too large. Maybe we thought we could make it happen, but we can’t.”

Still, professional societies must get involved as “responsible stewards of patient care. We’re the advocates for our patients, and if we don’t manage this, someone else [will],” Holmes commented. “We have the clinical expertise and we can make a difference. We know that funding for health care is not endless.” The momentum began, he added, when the regulatory and reimbursement authorities reached out for assistance.

Holmes urged professional societies to engage in communication with industry, government agencies, patient advocates and the scientific community.

“What then is the TVT Registry? It’s getting our feet wet,” he acknowledged. “[But] it has the potential to make a huge difference in how we evaluate [and] bring along new devices—and make sure they do the things we think they should do and help the patients we think they should [help].”

What a registry can do

The presentation provoked debate among the panelists over what registries can—and cannot—achieve. The question is, “[c]an you ever look at registries alone . . . to compare forms of treatment?” asked William S. Weintraub, MD, of Christiana Care Health Services in Newark, Del. Treatment bias can never be entirely overcome, he said, but large sample sizes and adjustment for baseline differences may help, particularly when the gap between two treatments is wide.

TCT Course Director Gregg W. Stone, MD, of Columbia University Medical Center, New York, countered: “I’ll be a little bit stronger. I think you can almost never use registries to make comparative effectiveness decisions in health care [because it is impossible to eliminate confounders]. If you want randomized trial results, you need to do a randomized trial.”

“On the other hand,” Pamela S. Douglas, MD, of Duke Clinical Research Institute in Durham, N.C., said, “when you want to know what is happening in clinical care . . . registries are invaluable. We should recognize that the world doesn’t always follow the way we create and carry out clinical trials.” That information, in turn, can inform trial design, she added.

Stone agreed, noting that “registries are wonderful [ways] to see how treatments are being provided and to look for low-frequency [adverse safety] events.”

As registries evolve—providing infrastructure for randomized trials or serving as platforms for regulatory change—“we have to be very specific about [defining their] function,” concluded John D. Carroll, MD, of University of Colorado Denver in Aurora, Col.