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Health Tracking

FROM THE FIELD

Clinical Use Of Medical Devices In The ‘Bermuda Triangle’

Abstract

 
The pace of medical technological development shows no sign of abating. Analyzing the effect of major federal health agencies on the availability of such technology is critical. This paper describes functions of three government health agencies: the Centers for Medicare and Medicaid Services (CMS), the Food and Drug Administration (FDA), and the National Institutes of Health (NIH). Certain medical technologies fall into gaps between these agencies, which pose challenges in today’s era of demand for evidence-based medicine. We suggest new policy and pragmatic strategies that can close the gaps and move decision making relevant to technology forward more rapidly than is now the case.

Much has been written about these agencies’ important roles in the process of medical device development, evaluation, and use.² However, much less is known about how the interaction (or lack thereof) among these agencies influences the process. Potential problems have been highlighted by reports questioning the clinical safety and utility of several FDA-approved, CMS-covered devices. In this paper we outline how the lack of systematic integration of policies among these agencies has resulted in the diffusion of unproven, and in some cases, potentially harmful medical devices. We argue that under certain circumstance, devices can disappear into a "Bermuda Triangle" between these agencies, evading the rational process of development, evaluation, and coverage that would ideally exist for therapies used in routine clinical practice. Our goal is to propose a framework that balances adequate evaluation with timely access to important new technologies.

Legislative Mandates

Top Editor's Notes Legislative Mandates Federal Oversight And Changing... Successes And Missed... A Way Forward: Systematic... How To Avoid More... Notes

 
Space limitations preclude a detailed description of the three agencies and their legislative mandates; we review them briefly here, beginning with the NIH.

The NIH mission is to uncover new knowledge by research in its own laboratories and by supporting nonfederal researchers. The NIH does not have a regulatory role in any direct sense. However, as evidenced by the recent report on the Women’s Health Initiative, the technologies it chooses to study or evaluate can greatly influence medical practice.³ The NIH devotes a small proportion of its resources to directly evaluating products that are already approved by the FDA; that role largely rests with the private sector.

The FDA Center for Devices and Radiological Health (CDRH) regulates all medical devices, from wheelchairs to radiation-emitting electronic devices. There are three pathways to market for a medical device.⁴ (1) The simplest devices are generally exempt from having to submit any paperwork to the FDA and are governed by general manufacturing practice (GMP) regulations. (2) The vast majority of devices enter the market through 510(k) submission, in which the manufacturer demonstrates substantial equivalence to an already marketed product. This does not usually require controlled clinical evaluations to understand risks, benefits, or clinical effectiveness. (3) High-risk devices or new technologies that the FDA has not previously evaluated are usually submitted through the premarket approval (PMA) application process. Most devices are approved for marketing on the basis of small to modest-size clinical trials done for a relatively narrow indication. The FDA regulates devices but does not evaluate or "approve" particular medical procedures.

Because of its size, the CMS (formerly HCFA) and its reimbursement decisions have a major impact on other payers’ policies, including adoption of new medical technologies. To be reimbursed by Medicare, items or services must have FDA approval for at least one indication (if FDA approval is required at all). There is one important exception: Medicare can cover certain devices designated by the FDA as experimental (Category B) during the experimental phase.⁵ Items or services also must fall into one of Medicare’s statutorily defined benefit categories and not excluded by statute, and they must be deemed "reasonable and necessary" either by the regional Medicare contractors or at the national level through a national coverage decision (NCD). A billing code must be established for the technology to allow a claim to be properly filed, and a payment rate must be established at either the local or national level. Coverage decisions are often made at the regional or local level, which could mean that coverage is not consistent throughout the entire country. Many of the more complex, controversial technologies are addressed at the national level. Since the late 1990s, the CMS has adapted an evidence-based framework for its NCDs.⁶

Federal Oversight And Changing Use Of Devices

Top Editor's Notes Legislative Mandates Federal Oversight And Changing... Successes And Missed... A Way Forward: Systematic... How To Avoid More... Notes

 
Devices are approved for much narrower indications than are eventually used in practice. Manufacturers, physicians, and patients all have an interest in expanding a device’s uses. An important question, then, is how devices approved for one indication are used for another. The answer lies in part in the limits Congress has set for federal agencies in monitoring and regulating medical practice.

Congress has made it clear in numerous situations that it does not want the FDA regulating medical practice. It has also directed the CMS to give deference to professional standards of care. Off-label use of a medical device allows clinicians to discover new uses in an experiential, rather than an experimental, manner. This experiential system sometimes leads to common off-label uses that become the community standard of practice. Many, perhaps most, of these new uses are ultimately beneficial, but without a formal method of evaluation, some widely adopted applications of technologies can be nonbeneficial or even harmful to patients.

How prevalent are devices and procedures that become the "standard of care" for a particular indication without formal clinical evaluation? There is no direct study to address this question, but the issue can be illustrated with several well-known procedures that involve devices. One of the best-known examples is coronary artery bypass graft (CABG) surgery, which according to Matthew Brenner and colleagues "became a standard of care...before its efficacy had been proved in organized clinical trials to determine patient selection, techniques, and indications."⁷ As the expanded examples illustrate below, the situation with CABG is by no means unique.

Pulmonary artery catheter (PAC). The PAC was first used in 1970, some six years before Congress passed the Medical Device Amendments to the Food, Drug, and Cosmetic Act. Initially, its uses were modest, as were its claims. The PAC was never subjected to a controlled clinical trial. Over a period of twenty years, as intensive care medicine expanded, so did use of the PAC. The diseases for which it was adopted included severe congestive heart failure, shock, sepsis, and acute respiratory distress syndrome (ARDS).⁸ It is also used in a wide variety of routine and emergency surgical procedures. The CMS has reimbursed all clinical uses of the PAC since its inception.

In the early 1990s a large prospective observational study was undertaken to better understand the device’s safety and efficacy in critical care medicine. Using advanced methodological techniques to control for the potential bias that those receiving PACs were more ill than those not receiving the device, Alfred Connors and colleagues found that patients receiving a PAC had significantly higher morbidity and mortality. When they published their study, editorialists questioned the utility of the PAC, even for "approved" uses.⁹ Other retrospective studies have questioned the device’s safety and efficacy, even for routine procedures.¹⁰

Lung volume reduction surgery (LVRS). LVRS was reintroduced in the mid-1990s to treat severe emphysema.¹¹ The principal breakthrough for this procedure was the use of a medical device—bovine pericardial strips—to prevent air leaks following the lung resection. Morbidity and mortality due to air leaks was the main reason that the procedure was abandoned after it was developed in the 1950s.

Bovine pericardial strips were initially submitted to the FDA in 1983 via the 510(k) premarket notification system for the repair of ruptured or damaged hernias or other soft-tissue membranes. Clinical studies demonstrated that bovine pericardial strips in LVRS reduced the occurrence and duration of air leaks and drainage time.¹² The FDA did not require the proof of efficacy of the LVRS procedure per se because the strips were used for sealing tissue in other procedures.

After publication and presentation of promising results from early case series, clinical use of LVRS spread rapidly.¹³ Several medical centers sent promotional brochures advertising "emphysema treatment centers" to clinicians hundreds of miles away. Estimates suggested that more than 2,000 procedures were performed on Medicare-eligible patients before the CMS became aware of its use in clinical practice.¹⁴ Early in 1995 the CMS (then HCFA) officials noted a spike in a relatively uncommon diagnosis-related group (DRG) code (multiple wedge resection), which providers were using to obtain payment for LVRS. After discovering the source, the CMS undertook a review of outcomes for people for whom claims were filed. In a review of claims and mortality records, the CMS discovered that 20 percent of patients died within thirty days of undergoing the procedure.

Lung cancer screening with spiral computed tomography (CT). The first clinical CT scanners introduced between 1974 and 1976 were dedicated to head imaging only, but whole-body systems soon became available. About 6,000 CT scanners are now installed in the United States. Like the PAC, CT scanners were introduced before the Medical Device Amendments were passed, so they did not undergo the evaluation associated with the PMA process. All major changes to CT scanners have come through the 510(k) process, so the FDA has not subjected incremental changes in scanners or their use to controlled clinical evaluation.

A new generation of "spiral" or "helical" CT scanners has been developed recently, capable of detecting very small lesions in the lung. Early uncontrolled studies have found that this technology shows promise for the early detection of lung cancer.¹⁵ Their benefit in reducing lung cancer–related mortality is unknown.¹⁶ "Positive" screening scans can precipitate patient anxiety and costly and potentially risky follow-up evaluation. Nevertheless, many clinicians have embraced this technology. A number of independent "body imaging" centers have sprung up around the country, marketing CT screening directly to people at higher risk for lung cancer (such as current and former smokers).

From a regulatory perspective, spiral CT is approved for imaging, and it is unlikely that the FDA could insist on a definitive clinical study to assure that these uses are appropriate. Medicare does not reimburse CT scans, but it does cover services used to evaluate "positive" scans. Given that fifteen to twenty million current and former smokers are enrolled in Medicare, the cost of paying for further evaluation of positive screens could be a substantial burden on the Medicare Trust Fund.

Successes And Missed Opportunities

Top Editor's Notes Legislative Mandates Federal Oversight And Changing... Successes And Missed... A Way Forward: Systematic... How To Avoid More... Notes

 
These technologies illustrate a variety of ways in which medical devices and related procedures can slip through the policy cracks between the federal agencies that are designed to ensure that technologies’ safety and effectiveness are established before they are used and reimbursed widely in clinical practice. Below we describe how the three agencies collaborated to address potential problems when they were brought to light. Their methods, while laudable, have been ad hoc and are not a standardized part of day-to-day operations. We conclude by describing a template for coordination to improve future use of new device-related technologies.

Pulmonary artery catheters. Concern over the safety of PACs prompted the FDA and NIH to jointly sponsor a workshop on the topic.¹⁷ Representatives from the Society for Critical Care Medicine, the American Association of Critical Care Nurses, the American College of Chest Physicians, and the Society for Thoracic Surgery were invited. Afterward the NIH designed two multicenter randomized trials of PAC use, one focusing on patients with severe heart failure and the other on patients with ARDS and sepsis. In response to other concerns, the professional societies jointly agreed to develop and market a national educational curriculum to improve knowledge and practice concerning the PAC. The CMS continues to reimburse physicians for placing the PAC under Medicare Part B. The hospital’s cost of using PACs for specific indications has been calculated into DRG payments.

Lung volume reduction surgery. After discovering that LVRS was being performed on Medicare beneficiaries, the CMS asked the Agency for Healthcare Research and Quality (AHRQ) to perform a systematic review of LVRS. The agency’s report found little compelling evidence of benefit for the procedure and revealed concerns about safety.¹⁸ As a result of these findings and mortality rates noted above, in fall 1995 the CMS announced that it would no longer pay for LVRS because of the absence of established clinical benefit combined with concerns about excess mortality for persons undergoing the procedure. Simultaneously, the National Heart, Lung, and Blood Institute (NHLBI) and a group of clinicians designed a randomized controlled study of LVRS for the Medicare population. A unique, unprecedented feature of this study is that the CMS agreed to pay for all related medical care costs for patients enrolled in the evaluation. A patient subgroup at very high risk for perioperative mortality was found and reported on in 2001.¹⁹ Trial results for the remainder of patients were published in May 2003; the study found no overall survival benefit in LVRS compared with rehabilitation patients only, but it did find significant improvements in exercise capacity and quality of life. Post hoc analyses identified one subgroup of patients with improved survival. A companion cost-effectiveness analysis showed that LVRS was not cost-effective, with an incremental cost-effectiveness ratio of $190,000 per quality-adjusted life year (QALY) saved.²⁰ The CMS is reviewing its coverage policy based on these results.

Spiral CT scanning for lung cancer. The federal response to spiral CT screening for lung cancer is less well developed than in the two previous examples. In response to an urgent call for evaluation, the NIH announced in spring 2002 that it would sponsor a multicenter randomized trial of CT screening for lung cancer.²¹ That the trial results are many years away poses a dilemma for clinicians and policymakers alike, now that screening centers have become widespread. The NIH is not collaborating with the FDA or CMS to develop a policy for addressing CT screening for lung cancer. The FDA has noted that it does not support CT screening for any indication.²² The CMS does not have statutory authority to pay for screening tests (breast, prostate, and colon cancer screening are exceptions that were made through separate legislation) but, as noted above, will pay for evaluation of positive scans, as this is considered to be an evaluation of a suspected medical condition.

A Way Forward: Systematic Evaluation Of Technologies

Top Editor's Notes Legislative Mandates Federal Oversight And Changing... Successes And Missed... A Way Forward: Systematic... How To Avoid More... Notes

 
Ideally, the federal government’s investigational, regulatory, and payment framework should be designed to balance the need for adequate clinical evidence with the desire to maintain a high level of innovation in health care technology. The obligation to avoid widespread dissemination of harmful or worthless technologies must be balanced against the possibility of creating barriers to future medical breakthroughs.

To find a better balance between these goals, improved cooperation between the CMS, FDA, and NIH is needed. Agencies need to coordinate their efforts in three domains: identification, evaluation, and financing of new clinical uses of devices and related procedures. This can be accomplished without creating additional bureaucracy or legislation. Below we suggest ways to use established policy mechanisms to identify device issues and streamline the evaluation process.

Identification. Safety and efficacy issues with medical devices and related procedures will come to light only if federal agencies are allowed to monitor them. What typifies the technologies that we believe fall through the monitoring cracks? Therapeutic and diagnostic procedures that use established devices for new indications usually do not receive systematic, rigorous evaluation. Nor do older devices that have become a standard of care without rigorous study. The FDA should withdraw approval for and the CMS should not pay for devices and related procedures that are found to be ineffective or harmful.

Given their national scope, the three agencies are uniquely positioned to identify important medical-device issues on a scale that is not possible in the private sector. The NIH, with its vast network of experts in all fields of medicine, is often the first to know about an emerging use of a device-related technology, even if it is not currently sponsoring trials. For example, the Early Detection Research Network (EDRN), funded by the National Cancer Institute (NCI), is designed to develop biological indicators of disease, many now based on the new sciences of genomics and proteomics. The EDRN has the potential to discover new products, and, because of its connection to the NIH, the NIH can alert the FDA and CMS of a new product with high potential for impact well before such products are widely disseminated. The FDA is often made aware through device applications and through the investigational device exemption (IDE) process, in which studies are initiated that will come to the agency for product approval. As the LVRS example shows, the CMS’s computerized records can identify increases in submitted claims as a way of identifying rapid growth of a particular technology. In addition, medical directors working for the CMS’s regional carriers are often the first to recognize the early diffusion of device-related technologies.

Establishing a mechanism whereby these agencies could alert each other about emerging uses of new or existing technologies would be an important first step toward identifying those that could be diffusing ahead of clinical evidence regarding safety and effectiveness. The CMS recently established an internal Medical Technology Council, to enable increased coordination within the CMS and between it and other agencies. The council aims to speed availability of important technologies and identify technologies that have undergone inadequate evaluation or become obsolete.

AHRQ could also play a pivotal role in identifying ineffective, unsafe, or inadequately tested technologies. Either directly or by funding a center to identify these technologies that fall into the gaps between agencies, AHRQ could assist in setting research and programmatic priorities. This could be done under its authority granted by the Food and Drug Administration Modernization Act (FDAMA) of 1997 to establish Centers for the Education and Research of Therapeutics (CERTs). A center devoted to devices and related procedures would be well within this mandate.

The FDA is developing another option to improve evaluation and information dissemination regarding devices. Its CDRH is attempting to develop an Interagency Agreement with the National Institute of Biomedical Imaging and Bioengineering (NIBIB) for a joint laboratory. The two organizations would share both the laboratory facility and staff who would be aware of both agencies’ roles and responsibilities. Because technology assessment is part of both agencies’ missions, this experiment could provide an opportunity for staff to alert management about the use and potential of new devices.

A simple but potentially effective approach is sharing minutes from advisory panels within disciplines among the three agencies. Because these documents are in the public domain, developing simple e-mail distribution lists could facilitate information transfer among those who can take action. Finally, in a few cases, scientific experts serving on one agency’s advisory panel could serve on the panel of another agency, again providing information interchange with no increase in bureaucracy.

Evaluation. After issues concerning device-related technologies are identified, there must be an evaluation phase. Initially, this will need to involve study of retrospective data, which are sometimes available through the FDA’s postmarketing surveillance processes. As we have noted, however, FDA regulatory processes often limit the robustness of the data for addressing the clinical issue related to the device and related procedure. The CMS’s Medicare claims records can sometimes identify outcomes related to new uses of medical devices, although the problem of bundling new uses in established procedure codes means that administrative claims often lack specificity for the procedures of interest. AHRQ has considerable expertise in evaluation of existing evidence and retrospective data and could contract with the CMS to perform these functions.

Despite their availability, retrospective data from the FDA and CMS are usually insufficient to address fundamental questions about the safety and effectiveness of emerging medical technologies. In this case, prospective, high-quality studies will need to be performed. This is where the financing issue comes into play.

Financing. The NIH designs and sponsors high-quality clinical trials. Through its extramural grants program, it could support investigators who are experienced in conducting clinical research on devices and related procedures. As shown by the PAC example, professional societies can also play a role in trial design. As noted for spiral CT screening, however, the expense for clinical care in large trials can be daunting, especially when patient care is involved. The NIH traditionally is reluctant to pay for patient care that occurs as part of trials. As shown by the LVRS example, partnering with the CMS might be one approach to addressing this problem.

The CMS already provides some resources to support the evaluation of emerging technology. CMS contractors generally pay all costs associated with new devices that have an IDE from the FDA. In addition, since September 2000 the CMS has paid the routine costs of care for Medicare patients enrolled in most federally approved clinical trials. When researchers and reviewers at the NIH and FDA have concerns about the use of particular devices or certain procedures, the CMS can be alerted and consider implications for current reimbursement policies. To promote this coordination, the information-exchange mechanisms noted above could be used to improve communication among agency authorities with related expertise.

How To Avoid More Bureaucracy

Top Editor's Notes Legislative Mandates Federal Oversight And Changing... Successes And Missed... A Way Forward: Systematic... How To Avoid More... Notes

 
Arranging for a systematic mechanism for the timely exchange of information among agencies raises the specter of additional bureaucracy in organizations that are already heavy in bureaucracy. Although we acknowledge this danger, and each agency will have to monitor changes in performance or behavior that would become bureaucratic, we believe that our recommendations will avoid this undesirable outcome. First, only a handful of technologies should come to the attention of multiple organizations through this mechanism. For example, the CDRH receives only about forty to sixty PMAs per year, representing the high end of new technology. It is likely that only half to two-thirds of these have serious potential to affect reimbursement issues. Attention to these high-end PMA devices and selected 510(k) devices (a subset of those that require clinical data for approval), rather than all possible devices, reduces the need for a large bureaucracy.

Second, our recommendations are systematic but not involved. We have some evidence regarding this latter recommendation. The CMS and FDA recently worked together on the approval and coverage for drug-eluting stents—devices that release a medication into the patient to reduce high rates of restenosis. Based on our recent successful experience with communication across agencies with regard to these devices, it appears that only a few meetings and consistent e-mail conversation were necessary to achieve efficient coordination. Identifying the personnel involved along the continuum from research to regulatory submission to coverage and reimbursement decisions should not prove difficult for most technologies that would fall under these recommendations.

The current uncoordinated federal system of evaluating and reimbursing device-related technologies has led to diffusion and widespread use of unproven technologies, with attendant concerns about safety and efficacy. With only modest budgetary implications (but perhaps major changes to interagency working relationships), coordinated evaluation of these technologies could greatly improve. A collaborative framework between the three HHS agencies (and possibly four if AHRQ were included) can provide a recipe for success. Such collaboration will no doubt raise concerns regarding increased barriers for new technologies. The alternative of continued diffusion of technologies of unknown worth, however, justifies continued efforts to improve collaboration.

Editor's Notes

Top Editor's Notes Legislative Mandates Federal Oversight And Changing... Successes And Missed... A Way Forward: Systematic... How To Avoid More... Notes

 
Larry Kessler is director of the Office of Science and Technology, U.S. Food and Drug Administration, in Rockville, Maryland. Scott Ramsey is a physician and associate member of the Fred Hutchinson Cancer Research Center in Seattle, Washington. Sean Tunis is chief medical officer of the Centers for Medicare and Medicaid Services in Baltimore, Maryland. Sean Sullivan is a professor of pharmacy and health services and director of the Pharmaceutical Outcomes Research and Policy Program at the University of Washington in Seattle.

The views presented here do not necessarily reflect those of the Food and Drug Administration or the Centers for Medicare and Medicaid Services.

Notes

Top Editor's Notes Legislative Mandates Federal Oversight And Changing... Successes And Missed... A Way Forward: Systematic... How To Avoid More... Notes

 

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