Table 4 Primary and key secondary endpoints

Primary endpoints:

 1. To test if the percentage of change of the RIII area of the flexion reflex at the time point t60 post-drug administration vs the pre-drug time point, differs in the tapentadol period as compared to the placebo period, at the sensitized lower limb.

 2. To test if the percentage of change of the N13-SEP amplitude at the time point t60 post-drug administration vs the pre-drug time point, differs in the tapentadol period as compared to the placebo period, at the sensitized upper arm.

Key secondary analyses of the primary endpoints:

 1. To test if the percentage of change of the RIII area of the flexion reflex at the time point t60 post-drug administration vs the pre-drug time point, differs in the pregabalin and/or lacosamide period as compared to the placebo period, at the sensitized lower limb.

 2. To test if the percentage of change of the N13-SEP amplitude at the time point t60 post-drug administration vs the pre-drug time point, differs in the pregabalin and/or lacosamide period as compared to the placebo period, at the sensitized upper arm.

 3. To test if the percentage of change of the R2 recovery cycle at 500 ms interstimulus time interval at the time point T60 post-drug administration vs the pre-drug administration differs in the tapentadol, pregabalin and/or lacosamide periods as compared to the placebo period.