To Evaluate the Efficacy and Safety/Tolerability Profiles of G-CSF in Subjects With Mild to Moderate Alzheimer's Disease

This is a randomized open-label Phase 2 trial with parallel design using no-treatment group as control. Subjects in the treatment arm will receive subcutaneous G-CSF with the dosage of 10 microgram/kg/day, for 5 continuous days in the first week. The second dosage will be given in the 12 week. If subjects has received Donepezil already, the Donepezil will be concomitantly used in a stable dose (the same dose as pre-entering this study) during the study. Background data and general medical history will be registered on the screening visit (Visit 1, started four weeks or less before Visit 2). Subjects fulfil the inclusion criteria 1) age between 50 to 85 years old; 2) those who were diagnosed as AD and the supporting evidences from the brain computed tomography or Magnetic Resonance Imaging scan within 12-months; 3) Mini-Mental State Examination scores of 10 to 26, and, 4) Clinical Dementia Rating score of 1 or 2. Subjects with clinically significant medical or neurological disorders, other than AD, that may affect cognition will be excluded Additional inclusion criteria included Modified Hachinski Ischemic score of ≤ 4, Hamilton Psychiatric Rating Scale for Depression score of ≤ 12and a reliable caregiver who is sufficiently familiar with the subject and is willing to provide the accurate data. Participants will receive standard physical examination in all visits. Serum tests include complete blood count (CBC),total bilirubin, creatinine, blood urea nitrogen (BUN), uric acid, aspartate transaminase (AST), alanine transaminase (ALT), total protein, albumin, Vitamin B12, folate, T4, thyroid-stimulating hormone (TSH), HbA1c, rapid plasmin reagin (RPR)/Treponema pallidum haemagglutination (TPHA) will be also obtained.