 This proposal aims to assess whether a switch from efavirenzemtricitabinetenofovir disoproxil fumarate to elvitegraviremtricitabinetenofovir disoproxil fumaratecobicistat will be associated with reversal of sleep and cognitive disturbances. Demonstrating changes upon withdrawal of drug and substitution of a drug regimen not known to have an impact on sleep or cognition may represent the best option to determine whether use of EFV is associated with effects on sleep and cognition beyond the immediate period following initiation of drug. 