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Trial Design: Pain Sections
Author Bio
Introduction
Placebo Effects
Single Dose Trials
Repeated Dose Trials
Explanatory Versus Pragmatic
Currently selected section: Dose-Response
Parallel Group Versus Crossover
Conclusion
 

 

Chapter 1: Clinical Trials of Pain Treatment: Dose-Response; Relative Potency; Combinations

 
         

Does this data suggest that Drug S will be a useful additive to morphine?

You answered:

Selection BNo, this data does not suggest that Drug S will be a useful additive to morphine.

INCORRECT

The unanswered question is whether one could get the same enhancement of analgesic with equal or less sedation by giving a higher dose of morphine alone. The addition of a higher morphine dose would convert this to the type of relative potency design discussed above.

The study design illustrated in Figure 6.5, a 2x2 factorial, actually satisfies the requirements for an analgesic combination as specified in the 1992 FDA analgesic development guidelines (http://www.fda.gov/cder/guidance/old041fn.pdf), and drug companies have frequently carried out such 2x2 factorial studies. However, the guidelines intended this design to be used for combinations of opioids with anti-inflammatory drugs, whose central nervous system side effects are minimal.