ABSTRACT
I. Introduction.......................................................................................... 161
II. Design of Analgesic Drug Trials ........................................................ 162
A. Selecting the Target Patient Population ....................................... 162
B. The Choice of Control Group....................................................... 163
C. Outcome Measures........................................................................ 164
D. Duration of Study ......................................................................... 166
E. Design ........................................................................................... 167
1. Parallel-Group Design ............................................................ 167
2. Add-on Design ........................................................................ 168
3. Crossover-Design .................................................................... 168
III. Interpretation of Results ...................................................................... 169
IV. Unique Challenges in the Analgesic Trial .......................................... 169
V. Conclusion ........................................................................................... 170
References........................................................................................................ 170
Tremendous groundwork has been laid over the last half century by pioneer
researchers in analgesic drug evaluation. Early analgesic trials to evaluate the
properties of opioid drug products brought out critically important insights
through in vivo human assays, the single-dose relative potency studies. These
trials were designed to answer the basic question, whether a test intervention had
any analgesic effect. These early trials attempted to accurately and reliably
measure pain, the subjective outcome, in the context of a clinical experiment.
The clinical pharmacology experiments performed by these early researchers
have had a lasting effect on the field. Their legacy was the modern randomized
controlled clinical trial in analgesic drug evaluation.
