FORMULATION, DEVELOPMENT AND BIOLOGICAL EVALUATION OF RIVASTIGMINE LOADED LIPOSOMES FOR THE TREATMENT OF ALZHEIMER'S DISEASE

Alzheimer’s disease is a chronic neurodegenerative disorder associated with progressive destruction of cholinergic neurons. Currently, there is no therapy which can reverse the progression of Alzheimer’s disease. However, some drugs like memantine, donepzil, rivastigmine etc. are used to improve the quality of life of patients with Alzheimer’s disease. Practically, it is desired to achieve and maintain high therapeutic level of anti-Alzheimer’s drug in the brain; nevertheless, it is difficult to do so due to blood brain barrier. This problem could be overcome by formulating liposomes of anti-Alzheimer’s drugs. In this background, the present investigation was aimed at formulating rivastigmine liposomes by stationary phase interdiffusion method to improve its penetration and distribution in brain. The prepared formulation showed encapsulation efficiency of about 70%. The in vivo and in vitro release profile showed sustained release of rivastigmine from the liposomes.  Moreover, a significantly higher level of rivastigmine was found in the brain with liposomes as compared to its solution. Finally, the effect of rivastigmine liposomes on scopolamine-induced memory deficits was assessed by novel object recognition test. Rivastigmine liposomes showed procognitive effect for the prolonged duration (48 hr) as compared to its solution (24 hr). The results of the present study suggest that delivering rivastigmine in the brain through liposomes could be a much better approach for the management of Alzheimer’s and other neuropsychiatric diseases.

Key Words: Alzheimer’s disease, rivastigmine, liposomes, cholinergic neurons, procognitive effect