Rivastigmine for HIV-associated neurocognitive disorders: a randomized crossover pilot study

Area of Science:

• Neuroscience
• Pharmacology
• Infectious Diseases

Background:

• HIV-associated neurocognitive disorders (HAND) remain a challenge despite effective antiretroviral therapy.
• Cognitive deficits in HAND can significantly impact patients' quality of life and daily functioning.
• Acetylcholinesterase inhibitors, like rivastigmine, are used for other neurodegenerative conditions and are being explored for HAND.

Purpose of the Study:

• To evaluate the efficacy and safety of oral rivastigmine in treating HAND.
• To assess rivastigmine's impact on cognitive function, specifically processing speed, attention, executive function, and motor skills.
• To determine the safety profile of rivastigmine in a cohort of long-lasting, aviremic HIV+ patients.

Main Methods:

• A randomized, double-blind, placebo-controlled, crossover study involving 17 aviremic HIV+ patients with HAND.
• Patients received oral rivastigmine (up to 12 mg/day) for 20 weeks, followed by placebo, or vice versa.
• Efficacy was measured using the Alzheimer's Disease Assessment Scale-Cognitive Subscale (ADAS-Cog) and individual neuropsychological tests. Safety was monitored through adverse events and laboratory tests.

Main Results:

• Rivastigmine did not significantly improve ADAS-Cog scores, the primary outcome.
• A significant improvement was observed in processing speed (Trail Making Test A) with rivastigmine treatment (p = 0.03).
• No other significant cognitive improvements were noted, although one measure of executive functioning approached significance (p = 0.069). Adverse events were frequent but comparable to other rivastigmine studies, with no safety concerns.

Conclusions:

• Oral rivastigmine demonstrated a potential benefit in improving psychomotor speed in aviremic HIV+ patients with HAND.
• The drug was not effective in improving overall cognitive function as measured by ADAS-Cog.
• Further investigation using the more tolerable transdermal formulation of rivastigmine is recommended for HAND treatment.