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The multiple endpoints expert team was created in early 2004 and disbanded in early 2006. The team was chaired by Walt Offen (Lilly).

The expert team was formed to investigate clinical and statistical solutions to reverse multiplicity problems in clinical trials. Reverse multiplicity is encountered in clinical trials with multiple co-primary endpoints when an experimental treatment is required to demonstrate efficacy with respect to all co-primary endpoints (all endpoints must be significant at the 0.05 level) before regulatory agencies accept the treatment's effect for the disorder. Reverse multiplicity is quite common in clinical drug development. Examples include trials for treatment of Alzheimer's disease, osteoarthritis, chronic obstructive pulmonary disease, etc. The requirement to achieve significance for all co-primary endpoints is based on the statistical principle known as the intersection-union testing principle. This approach results in reduced study power and clinical trial sponsors need to increase the sample size to make up for the reduction in the statistical power.

Alex Boddy (Sanofi-Synthelabo), David Bristol (Purdue Pharma LP), Kun Chen (Bayer), Christy Chuang-Stein (Pfizer), Kati Copley-Merriman (Pfizer), Willard Dere (Amgen), Alex Dmitrienko (Lilly), Sam Givens (Hoffman-LaRoche), David Hall (Boehringer-Ingelheim), David Henry (Bristol Myers Squibb), Joe Jackson (Bristol Myers Squibb), Alok Krishen (GlaxoSmithKline), Gary Littman (Wyeth), Thomas Liu (Amgen), Jeff Maca (Novartis), Robb Muirhead (Pfizer), Laura Myerson (Biogen-Idec), Walt Offen (Lilly), Margaret Rothman (J&J), Steve Ryder (Pfizer), Paul Stryszak (Schering Plough), Gary Tollefson (Lilly), Julia Wang (J&J), Chyon-Hwa Yeh (Procter & Gamble).

Offen, W., Chuang-Stein, C., Dmitrienko, A., Littman, G., Maca, J., Meyerson, L., Muirhead, R., Stryszak, P., Boddy, A., Chen, K., Copley-Merriman, K., Dere, W., Givens, S., Hall, D., Henry, D., Jackson J.D., Krishen, A., Liu, T., Ryder, S., Sankoh, A.J., Wang, J., Yeh, C.H. (2007). Multiple co-primary endpoints: Medical and statistical solutions. A report from the Multiple Endpoints Expert Team of the Pharmaceutical Research and Manufacturers of America. Drug Information Journal. 41, 31-46.

Chuang-Stein, C., Stryszak, P., Dmitrienko, A., Offen, W. (2007). Challenge of multiple co-primary endpoints: A new approach. Statistics in Medicine. 26, 1181-1192.

PhRMA workshop (Clinical, Statistical, and Regulatory Challenges of Multiple Endpoints) was held on October 20-21, 2004 at Bethesda Marriott in Bethesda, MD to discuss clinical and statistical solutions to reverse multiplicity problems arising in clinical trials. The workshop was chaired by Walt Offen (Lilly) and the PhRMA multiple endpoints expert team played an important role in organizing and leading this workshop. Download the workshop's program.