Handbook of Medical Device Design

Richard C. Fries

• Editore: CRC Press
• Anno: 2019
• ISBN:
  9781000696950
• Edizione: 1
• Argomento: Tecnología e ingeniería
• Categoria: Ciencias biomédicas

First published in 2001: This handbook has been written to give those professionals working in the development and use of medical devices practical knowledge about biomedical technology, regulations, and their relationship to quality health care.

Section 1

Standards and Regulations

Chapter 1

FDA Regulations

Richard C. Fries, PE, CRE – Datex-Ohmeda, Inc. Madison, Wisconsin

Regulation of medical devices is intended to protect consumer’s health and safety by attempting to ensure that marketed products are effective and safe. Prior to 1976, the FDA had limited authority over medical devices under the Food, Drug, and Cosmetic Act of 1938. Beginning in 1968, Congress established a radiation control program to authorize the establishment of standards for electronic products, including medical and dental radiology equipment. From the early 1960s to 1975, concern over devices increased and six United States Presidential messages were given to encourage medical device legislation.

In 1969, the Department of Health, Education, and Welfare appointed a special committee (the Cooper Committee) to review the scientific literature associated with medical devices. The Committee estimated that over a 10-year period, 10,000 injuries were associated with medical devices, of which 731 resulted in death. The majority of problems were associated with three device types: artificial heart valves, cardiac pacemakers, and intrauterine contraceptive devices. There activities culminated in passage of the Medical Devices Amendments of 1976.

Devices marketed after 1976 are subject to full regulation unless they are found substantially equivalent to a device already on the market in 1976. By the end of 1981, only about 300 of the 17,000 products submitted for clearance to the FDA after 1976 had been found not substantially equivalent.

1.1 History of Device Regulation

In 1906, the Food and Drug Administration enacted its first regulations addressing public health. While these regulations did not address medical devices per se, they did establish a foundation for future regulations. It was not until 1938, with the passage of the Federal Food, Drug and Cosmetic Act (FFD&C) that the FDA was authorized, for the first time, to regulate medical devices. This act provided for regulation of adulterated or misbranded drugs, cosmetics and devices that were entered into interstate commerce. A medical device could be marketed without being federally reviewed and approved.

In the years following World War II, the FDA focused much of the attention on drugs and cosmetics. Over-the-counter drugs became regulated in 1961. In 1962, the FDA began requesting safety and efficacy data on new drugs and cosmetics.

By the mid-1960s, it became clear that the provisions of the FFD&C Act were not adequate to regulate the complex medical devices of the times to ensure both patient and user safety. Thus, in 1969, the Cooper Committee was formed to examine the problems associated with medical devices and to develop concepts for new regulations.

In 1976, with input from the Cooper Committee, the FDA created the Medical Device Amendments to the FFD&C Act, which were subsequently signed into law. The purpose of the amendments was to ensure that medical devices were safe, effective and properly labeled for their intended use. To accomplish this mandate, the amendments provided the FDA with the authority to regulate devices during most phases of their development, testing, production, distribution and use. This marked the first time the FDA clearly distinguished between devices and drugs. Regulatory requirements were derived from this 1976 law.

In 1978, with the authority granted the FDA by the amendments, the Good Manufacturing Practices (GMP) were promulgated. The GMP represents a quality assurance program intended to control the manufacturing, packaging, storage, distribution and installation of medical devices. This regulation was intended to allow only safe and effective devices to reach the market place. It is this regulation that has the greatest effect on the medical device industry. It allows the FDA to inspect a company’s operations and take action on any noted deficiencies, including prohibition of device shipment.

Recent regulations specific to medical devices are the Medical Device Reporting (MDR) regulation of 1984, the Device Reconditioner/Rebuilder (DRR) regulation of 1988, and the Safe Medical Devices Act of 1992.

1.2 Device Classification

A medical device is any article or health care product intended for use in the diagnosis of disease or other condition or for use in the care, treatment, or prevention of disease that does not achieve any of its primary intended purposes by chemical action or by being metabolized.

From 1962, when Congress passed the last major drug law revision, and first attempted to include devices, until 1976 when device laws were finally written, there were almost constant congressional hearings. Testimony was presented by medical and surgical specialty groups, industry, basic biomedical sciences, and various government agencies, including all the FDA. All of the viewpoints and arguments that we hear today were proposed, and considered in public discussion. Nearly two dozen bills were rejected as either inadequate or inappropriate.

The Cooper Committee concluded that the many inherent and important differences between drugs and devices necessitated a regulatory plan specifically adapted to devices. They recognized that some degree of risk is inherent in the development of many devices, so that all hazards cannot be eliminated, that there is often little or no prior experience on which to base judgements about safety and effectiveness, that devices undergo performance improvement modifications during the course of clinical trials, and that results also depend upon the skill of the user.

They therefore rejected the drug-based approach and created a new and different system for evaluating devices. All devices were placed into classes based upon the degree of risk posed by each individual device and its use. The Pre-Market Notification Process (510(k)) and the Pre-Market Approval Application (PMAA) became the regulatory pathways for device approval. The Investigational Device Exemption (IDE) became the mechanism to establish safety and efficacy in clinical studies for PMAAs.

1.2.1 Class I Devices

Class I devices were defined as not life sustaining, their failure poses no risk to life, and there is no need for performance standards. Basic standards, however, such as premarket notification (510(k)), registration, device listing, good manufacturing practices (GMP), and proper record keeping are all required. Nonetheless, the FDA has exempted many of the simpler Class I devices from some or all of these requirements. For example, tongue depressors and stethoscopes are both Class I devices, both are exempt from GMP, tongue depressors are exempt from 510(k) filing, whereas stethoscopes are not.

1.2.2 Class II Devices

Class II devices were also defined in 1976 as not life sustaining. However, they must not only comply with the basic standards for Class I devices, but must meet specific controls or performance standards. For example, sphygmomanometers, although not essential for life, must meet standards of accuracy and reproducibility.

Premarket notification is documentation submitted by a manufacturer that notifies the FDA that a device is about to be marketed. It assists the agency in making a determination about whether a device is “substantially equivalent” to a previously marketed predecessor device. As provided for in section 510(k) of the Food, Drug, and Cosmetic Act, the FDA can clear a device for marketing on the basis of premarket notification that the device is substantially equivalent to a pre-1976 predecessor device. The decision is based on premarket notification information that is provided by the manufacturer and includes the intended use, physical composition, and specifications of the device. Additional data usually submitted include in vitro and in vivo toxicity studies.

The premarket notification or 510(k) process was designed to give manufacturers the opportunity to obtain rapid market approval of these noncritical devices by providing evidence that their device is “substantially equivalent” to a device that is already marketed. The device must have the same intended use and the same or equally safe and effective technological characteristics as a predicate device.

Class II devices are usually exempt from the need to prove safety and efficacy. The FDA, however, may require additional clinical or laboratory studies. On occasion these may be as rigorous as f...