Rao, R.D., Michalak, J.C., Sloan, J.A., Loprinzi, C.L., Soori, G.S., Nikcevich, D.A., . . . Wong, G.Y. (2007). Efficacy of gabapentin in the management of chemotherapy-induced peripheral neuropathy. Cancer, 110, 2110–2118. doi: 10.1002/cncr.23008
115 patients with symptomatic chemotherapy-induced peripheral neuropathy (CIPN) were randomized to the order of receiving oral gabapentin or placebo for six weeks separated by a two week “washout” period and crossing over to the other treatment group for six weeks. Gabapentin doses (300 mg capsules) and identical placebo doses were escalated over three weeks to a target dose of 2,700 mg of gabapentin per day, or nine placebo capsules per day.
The study was a phase III randomized, double-blind, placebo-controlled crossover trial.
Primary outcomes were pain and neuropathy symptoms measured by NRS (0 = no pain and 10 = worst pain possible) and the ENS (0 = none and 3 = severe objective sensory loss or paresthesias that interfere with function). These self-report data were collected weekly in reference to a single day
Secondary measures included:
These data were collected at baseline, 6, 8, and 14 weeks.
No differences were noted between groups at baseline, 6, or 14 weeks in the average pain NRS and the ENS. However, worst pain was lower in the placebo followed by gabapentin group at 14 weeks (p = 0.05). The only significant difference between the groups was in the McGill Pain Rating Index, which showed lower pain in the gabapentin group at the end of the first six week treatment period (p = 0.03).
Gabapentin did not improve symptoms of CIPN.