One versus Two Adequate Studies for Providing Clinical Evidence of Effectiveness: Issues, concerns and benefits
*Jianliang Zhang, MedImmune 


Requiring one confirmatory trial at alpha level 0.00125 is usually considered an equivalent alternative to the requirement of two independent adequate and well-controlled trials at alpha level 0.05. However, many conscious and unconscious assumptions are involved in reaching this alpha equivalence. This discussion will focus on potential issues and concerns regarding these assumptions. In addition, two technical findings will be discussed.