Lamotrigine shows some benefit for HIV-associated painful sensory neuropathies

The objective of this study was to evaluate the efficacy and tolerability of lamotrigine (LTG) for the treatment of pain in HIV-associated sensory neuropathies. In a randomised, double-blind study, patients with HIV-associated distal sensory polyneuropathy (DSP) received LTG or placebo during a seven-week dose escalation phase followed by a four-week maintenance phase. Randomisation was stratified according to whether or not patients were currently using neurotoxic antiretroviral therapy (ART).

The number of patients randomised was 92 (62 LTG, 30 placebo) in the stratum receiving neurotoxic ART and 135 (88 LTG, 47 placebo) in the stratum not receiving neurotoxic ART. Mean change from baseline in Gracely Pain Scale score for average pain was not different between LTG and placebo at the end of the maintenance phase in either stratum, but the slope of the change in Gracely Pain Scale core for average pain reflected greater improvement with LTG than with placebo in the stratum receiving neurotoxic ART (p = 0.004), as did the mean change from baseline scores on the Visual Analogue Scale for Pain Intensity and the McGill Pain Assessment Scale and patient and clinician ratings of global impression of change in pain (p </= 0.02). The incidence of adverse events, including rash, was similar between LTG and placebo.

Simpson concluded that lamotrigine was well-tolerated and effective for HIV-associated neuropathic pain in patients receiving neurotoxic antiretroviral therapy. Additional research is warranted to understand the differing response among patients receiving neurotoxic antiretroviral therapy compared with those not receiving neurotoxic antiretroviral therapy.