NIS-LL: the primary measurement scale for clinical trial endpoints in diabetic peripheral neuropathy.

Regulatory authorities favour the use of clinical endpoints, over surrogate endpoints, to demonstrate the efficacy of therapeutic agents for diabetic peripheral neuropathy (DPN). Progress in the quantification of the severity of DPN has been observed in recent years. The NIS-LL (Neuropathy Impairment Score in the Lower Limbs) is a new scale which quantifies the neurological function in DPN. This scale for determining the neuropathy impairment in DPN optimises the chances of demonstrating clinical change following pharmaceutical intervention in patients with early-stage neuropathy. The use of the NIS-LL in clinical trials, together with other tests measuring nerve function, pain and risk of foot ulcer, provides the best opportunity to evaluate the efficacy of new therapeutic agents for the treatment of DPN.