Medical Device Testing on Human Subjects

Copyright © Charles S. Tritt, Ph.D.
April 6, 1997

1. Practice versus Research

   1. The objective in the practice of medicine is to enhance the well being of the individual patient.

      1. Validated practice involves the use of equipment and techniques that have been proven to be safe and effective for the particular clinical situation.
      2. Nonvalidated practice involves efforts to enhance the well being of the patients by means not proven to be safe or effective. Nonvalidated practice is generally justified only when the patient is in a medical crisis and there are no effective validated practices available.

   2. The objective in research is the generation of knowledge.

      1. Research is necessary to provide basic knowledge needed to develop new devices and techniques.
      2. Research is necessary to prove that a new device or technique is safe and effective.
      3. Research must be systemic and conducted under rigorously controlled conditions. It must be directed towards answering reasonably specific questions of scientific and medical interest.

2. Requirements for ethical use of humans in experiments

   1. The inquire must be scientifically sound and already advanced as far as possible by non-human experimentation. The objective of human research is generally to:

      1. prove that a new technique is safe and effective
      2. gain some basic known of human physiology.

   2. The tests and means of the research (protocol) should be reasonably believed to be able to provide the desired results.
   3. The research should be conducted by qualified individuals.
   4. Expected benefits should outweigh any expected risks. There should not be any less risky ways to obtain the same data.
   5. Research subjects must be fully informed to the risks involved in the research, understand these risks and freely volunteer to participate in the study.

      1. It can be argued that children and the mentally handicapped can not ever fully understand the risks involved in research and therefore should never be used as experimental subjects.
      2. It can be argued that prisoners can never freely volunteer and therefore should never be experimental subjects.
      3. Care should be taken not to put undue emotional pressure on potential subjects. It would be inappropriate to say to a potential subject, "think of all those poor sick children you could be help if you participate in this study."

   6. Experimentation should be stopped immediately if:

      1. the subject expresses a desire to end their participation
      2. the investigator has reason to believe that the experiment is likely to result in injury, disability or death of the subject.

3. Institutional Review Boards (IRB's) for the Protection of Human Subjects

   1. Most institutions now have IRB's. Institutions are required by the federal government to have an IRB if they receive federal funding. The IRB provides an independent, third party review of proposed research involving human subjects.
   2. Many institutions also have an IRB for animal research. The purpose and operation of the animal IRB is generally the same as the human IRB. Other than informed consent and prior use on animals the criteria used to evaluate animal protocols are generally the same as those for human protocols.
   3. Contact the IRB administrative office (currently the office of the V.P. of academics) for a packet of IRB instructions and materials. This packet provides detailed instructions and sample forms for the IRB approval process.
   4. Research protocol packets (plans) must be submitted to the IRB and approved before the research is conducted. These packets generally consist of:

      1. A special cover sheet
      2. One page project summary/abstract
      3. Project outline
      4. Informed consistent form
      5. An affiliation letter (if applicable)
      6. Instruments (forms or data sheets) to be used in the research.

   5. The MSOE IRB recognizes three categories of projects:

      1. Exempt - for projects that are exempt from IRB review. An abbreviated packet still must be submitted.
      2. Minimal Risk - for projects having an anticipated risk of harm to the subject no greater than those ordinarily encountered in daily life.
      3. Risk or Deception - for project having more than minimal risk or involving intentional deception of the subjects.

   6. IRB approvals must be renewed annually. Any changes in your protocol must be submitted for review and approval.

4. Regulation of Medical Devices

   1. The FDA has the authority to regulate the distribution and use of medical devices. The FDA also regulates the clinical testing of medical devices. The FDA must approve all new medical devices before they are marketed.

      1. The modification of an approved device is generally considered to be a new device for proposes of regulation and testing.
      2. The use of an approved device in a new way or for a new condition is also generally considered to involve a new device.

   2. The primary mechanism by which an unapproved device may be distributed for use on human subjects is through an Investigational device exemption (IDE). The IDE provides a mechanism for the clinical testing of new devices. This testing is generally required to prove the safety and efficacy before it can be approved.

      1. The FDA recognizes to categories of devices in regard to IDE approval requirements.

         1. Protocols and devices that involve insignificant risk (examples include dental devices and daily-wear contact lenses) require only local IRB approval.
         2. Protocols and devices that involve significant risk (examples include orthopedic implants, artificial hearts and infusion pumps) require both IRB and FDA approval.

      2. The criteria by which the IRB and FDA approves a protocol include:

         1. Risks to the subjects are minimized.
         2. Risks are reasonable relative to the knowledge to be gained.
         3. Subject selection is equitable.
         4. Informed consent materials and procedures are adequate.
         5. Provisions for monitoring the study are acceptable.
         6. Provisions for protecting patient information are acceptable.

   3. The FDA allows unapproved medical devices to be used without an IDE in three types of situations:

      1. Feasibility studies - involves studies at one institution involving no more than 10 patients. These studies generally involved modifications to or new uses of approved devices.
      2. Emergency use - allowed when the use of the device or technique offers the only alternative for saving the life of a dying patient. There must be substantial reason to believe the patient will benefit from the use of the device or technique. This type of use generally does not provide much scientific information because of the number of "uncontrolled" variables and small (n = 1) sample size.
      3. Treatment use - this exception has only been used of drugs but possibly could be applied to devices. This situation is similar to emergency use but the patient's disease or condition does not have to be life-threatening only serious.