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Ethical issues in clinical trials

Ethical issues in clinical trials. Bernard Lo, M.D. February 16, 2012. Conflicts of interest. None. Issues to discuss. Use of placebo control where an effective treatment exists Informed consent Participants who develop adverse outcomes. Osteoporosis RCTs.

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Ethical issues in clinical trials

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  1. Ethical issues in clinical trials Bernard Lo, M.D. February 16, 2012

  2. Conflicts of interest • None

  3. Issues to discuss • Use of placebo control where an effective treatment exists • Informed consent • Participants who develop adverse outcomes

  4. Osteoporosis RCTs • New drug + background Ca + vit D vs. background alone • Primary end point • Vertebral Fx at 3 y • Nonvertebral Fx, breast CA at 5 years

  5. Osteoporosis RCTs • Effective drugs for osteoporosis • Bisphosphonates • Estrogen • SERMs (raloxifene)

  6. Does placebo raise ethical concrens if effective treatment exists?

  7. Objections to placebo controlsif effective Rx • Withholding effective Rx intentionally harms participants • Unless patient fails or cannot tolerate Rx • Unless minor, self-limiting condition • Unless efficacy varies from trial to trial • Even if participant consents

  8. Interventions for control group: Helsinki #29 (2000) • Interventions must be tested against “best current prophylactic, diagnostic, and therapeutic methods” • Rejected “highest attainable and sustainable” www.wma.net

  9. Interventions for control group: Helsinki (2008) • Placebo necessary to determine safety and efficacy • Compelling and scientifically sound methodological reasons • No serious and irreversible harm www.wma.net

  10. Is this serious and irreversible harm? Active Placebo Hip Fx 0.7% 1.2% Vertebral Fx 2.3% 7.2%

  11. FDA may insist on placebo • Variable response to active drugs • Depression • Peptic ulcer disease • If active control, can’t tell if either drug superior to placebo in that trial

  12. Sponsor perspective • Why use placebo controls?

  13. Power • Enrolled 2500 participants • 90% power to detect 40% reduction in vertebral fractures at 3 years • What about power if active control?

  14. How to minimize the risk of serious, irreversible harm? • Exclude persons at unacceptable risk • Recent vertebral Fx • T score < - 4.5 • Enroll only those who failed or cannot tolerate other Rx

  15. How to minimize the risk of serious, irreversible harm? • Reduce risks during trial • Refer to treating MD if worsen • T score < - 4.5 • Osteoporotic Fx

  16. How to minimize the risk of serious, irreversible harm? • Change study design • Make osteoporosis the study endpoint • Problems with surrogate endpoints • Problems with FDA approval

  17. How to minimize the risk of serious, irreversible harm? • Do study where poor access to effective drugs? • Involve advocates in trial design

  18. Informed consent • Problem of how to ensure participants understand what is in consent form

  19. Strategies to enhance comprehension • Spend more time talking to participants • Questions and feedback • Shorter, simpler consent forms • Multimedia -- mixed evidence

  20. Strategies to enhance comprehension • Test comprehension of key features of study • In designing consent process, involve • Obstetricians and general internists • Patient advocacy groups

  21. Sponsor perspective • How do these suggestions impact on trial?

  22. Patient advocate perspective • When participants develop adverse outcomes, concerns about referral to treating MD? • Other approaches?

  23. Concerns about referral to treating MD • Poor access to care • Suboptimal management of osteoporosis

  24. Other approaches • Information or support for treating MDs • Referral to independent experts in osteoporosis

  25. Take home points • Ethical issues occur at each stage of clinical trial • Tradeoffs inevitable • Cannot rely on sponsor, FDA, IRB to assure that ethical issues addressed • Responsibility of investigator

  26. Osteoporosis RCTs • Role of sponsor • Designed the protocol • Managed the data • Held the data, carried out statistical analyses requested • Scientific advisory committee planned analyses before unblinding

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