The Perfect Clinical Trial.

Multiple phase III clinical trials have failed to show disease-modifying benefits for diabetic sensorimotor polyneuropathy (DSP) and this may be due to the design of the clinical trials. The perfect clinical trial in DSP would enroll sufficiently large numbers of patients having early or minimal disease, as demonstrated by nerve conduction studies (NCS). These patients would be treated with an intervention given at an effective and well-tolerated dose for a sufficient duration of time to show change in the end points selected. For objective or surrogate measures such as NCS and for some small fiber measures, the duration needed to show positive change may be as brief as 6-12 months, but subsequently, trials lasting 5-8 years will be required to demonstrate clinical benefits.