People living with HIV in the era of antiretroviral therapy (ART) continue to suffer high rates of neurocognitive disorder. This is a randomized control trial aiming to evaluate improvement of neurocognitive function after switching efavirenz (EFV) to rilpivirine (RPV). EFV based regimen is currently the first line ART in Thailand. There are several reports suggested that HIV-infected patients who took EFV based regimen had poorer neurocognitive function compared to the comparator. RPV, another first line regimen, has been known to have less neuropsychiatric side effects. We hypothesized that switching EFV to RPV could improve neurocognitive function.

People living with HIV (PLWH) in the era of antiretroviral therapy (ART) continue to suffer high rates of neurocognitive disorder. Previous report revealed that 36% of PLWH in Thailand had this condition. There are several reports suggested that HIV-infected patients who took efavirenz (EFV) based regimen had poorer neurocognitive function compared to the comparator. Rilpivirine (RPV), another first line regimen, has been known to have less neuropsychiatric side effects. We hypothesized that switching EFV to RPV could improve long term neurocognitive function.

PLWH (20 years and older) who received EFV-based regimen for at least 1 years at Chiang Mai University Hospital will be invited to this study. Neurocognitive function will be evaluated using 3 screening questions, International HIV Dementia Scale, Montreal Cognitive Assessment, and comprehensive neurocognitive battery test evaluating 6 different cognitive domains. The participants will be categorized in to 4 groups based on their neurocognitive test results; no evidence of neurocognitive deficit, asymptomatic neurocognitive impairment (ANI), mild neurocognitive disease (MND), and HIV associated dementia (HAD) using Frascati's criteria. The participants with ANI or MND and meet the eligibility criteria will be enrolled to this study. The participants will be randomized in to 2 arms; continuing EFV-based regimen or switching to RPV-based regimen. Neurocognitive function will be evaluated at 6 and 12 months.

Inclusion Criteria:

• Documented HIV infection
• Age 20 years old and above
• On EFV-based regimen (EFV and 2 Nucleoside Reverse Transcriptase Inhibitors) for at least 1 year prior to enrollment
• CD4 ≥ 200 cell/mm3 and viral load < 200 copies/mL within 12 months before enrollment
• Able to be read and write in Thai language
• Willing to sign informed consent and able to follow up
• The neurocognitive battery test is compatible with asymptomatic neurocognitive impairment (ANI) or mild neurocognitive disorder (MND) using Frascati's criteria

Exclusion Criteria:

• History of Traumatic Brain Injury, Developmental delay or intellectual deficit, or other neurological conditions have deleterious effects on neurocognitive test based on investigator opinion.
• Active syphilis or on going to treatment with positive for syphilis serological marker (rapid plasma reagin; RPR) in 3 Months before entry study
• Pregnancy
• Renal failure (creatinine clearance < 30 mL/min)
• Transaminitis in the past 3 months (≥5 UNL) Or Decompensated cirrhosis (child-pugh C)
• Moderate depressive score; Patient Health Questionnaire-9 score ≥ 10)
• Positive for any hepatitis B virus and hepatitis C virus serological marker in 3 Months before entry study
• History of treatment failure or drug resistance to EFV and or RPV
• Not suitable or contraindication for RPV (continue proton pump inhibitor drug)