Sixteen-Week Interventional Study to Evaluate the Clinical Effects and Safety of Rivastigmine Capsules in Chinese Patients with Alzheimer’s Disease

BACKGROUND: Rivastigmine is a cholinesterase inhibitor, approved for the treatment of mild-to-moderate dementia of Alzheimer's type. OBJECTIVE: To explore the efficacy and safety of the maximal tolerated dose of rivastigmine capsules in Chinese patients with mild-to-moderate Alzheimer's disease (AD). METHODS: The study was a multicenter, open-label, single-arm, phase IV clinical study in mild-to-moderate drug-naive AD patients treated with rivastigmine capsules. The primary endpoint was the changes in the total scores of Alzheimer's Disease Assessment Scale-Cognitive subscale (ADAS-Cog) from baseline to week 16. Secondary endpoints included changes in the scores of the following assessment scales and safety: Alzheimer's Disease Cooperative Study; Activities of Daily Living; Mini-Mental Status Examination (MMSE); Neuropsychiatry Index (NPI), and Caregiver Burden Inventory. RESULTS: 222 patients were enrolled. Of these, 136 (75.1%) patients received and maintained the effective dose (≥6 mg/d) of rivastigmine for at least 4 weeks. The ADAS-Cog scale score improved in rivastigmine-treated patients at week 16 compared with baseline (p < 0.001) by 2.0 (95% CI: -3.0 to -1.1) points, which met the pre-defined superiority criteria. NPI-10 and NPI-12 scores improved by 3.6 and 4.0 points at week 16 (p = 0.001, p < 0.001), respectively. A total of 107 patients (59.1%) experienced adverse effects (AEs) during the study; common AEs included nausea (20.5%), vomiting (16.6%), anorexia (7.8%), dizziness (7.7%), and diarrhea (7.2%). CONCLUSION: This was the first phase IV study on rivastigmine in mainland China. The study preliminarily demonstrated that rivastigmine capsules showed good tolerability and efficacy in mild-to-moderate AD patients with the maximal tolerated dose.