Efficacy and Safety of Yangxue Qingnao Pills in the Treatment of Mild to Moderate Alzheimer's Disease

Inclusion Criteria: Patients, Chinese speaking, in both gender are eligible to be included in the study only ifthey meet all of the following criteria:

1. Meets NIA/AA core clinical criteria for probable AD;
2. The body weight is between 45-90kg;
3. Aged ≥ 65 and ≤ 85 years old;
4. Mild to moderate stage of AD, defined as( MMSE score of 15 through 26) at baseline;
5. Has had an MRI scan performed at baseline that has confirmed with a diagnosis of AD,Medial temporal atrophy scale (MTA) is used for routine assessment of the medialtemporal lobe, and the MTA score need ≥1.5 (adjusted by age: 65-74 years ≥ 1.5 points, 75-84 years old ≥ 2.0 points);
6. Has a PIB-PET scan or CSF result consistent with the presence of amyloid pathology atscreening;
7. And the patients must have adequate vision and hearing to participate in studyassessments; has normal swallowing function, and can complete the medication;
8. Have a stable caregiver;
9. Can read simple articles and write simple sentences;
10. Informed consent, signed informed consent by legal guardian.

Exclusion Criteria: Patients who confirmed with any of the following excluding criteria conditions were notenrolled for the study:

1. Early-onset Alzheimer disease (oneset at <65 years of age) and moderate to severe ADdementia (MMSE 14-0);
2. Evidence of other reasons caused cognitive impairment, like vascular dementia,frontotemporal dementia, Parkinson's disease dementia, Lewy body dementia,Huntington's disease, subdural hematoma, communicating hydrocephalus, brain tumor,thyroid disease, vitamin deficiency Or other diseases that may cause cognitiveimpairment, or serious brain infections (including neurosyphilis, meningitis orencephalitis), etc.;
3. There are unstable mental disorders, including major depression (HAMD≥17), severeanxiety disorder (HAMA≥12 points), bipolar disorder, schizophrenia, etc.;
4. History of drug or alcohol abuse in the past 5 years;
5. Other uncontrolled chronic illnesses, such as severe arrhythmia (ventricular rate <60beats/min or >100 beats/min, or patients with myocardial infarction within 3 monthsbefore participating in the trial, or severe heart failure (NY classification III andIV), or severe abnormal blood pressure, systolic blood pressure ≤90mmHg or ≥180mmHg;
6. Severe liver or kidney dysfunction (alanine aminotransferase or aspartate transaminasewas more than 1.5 times the upper limit of normal, or serum creatinine was more thanthe upper limit of normal);
7. A history of taking cholinesterase inhibitors, memantine, or proprietary Chinesemedicines with clear nootropic effects within the past 1 month;
8. Has received medications that affect the central nervous system (CNS), excepttreatments for AD for less than 4 weeks; that is, doses of chronic medications thataffect the CNS should be stable for at least 4 weeks;
9. One of the following manifestations on cranial MRI:> 4 cerebral microhemorrhages,evidence of a prior macrohemorrhage, > 3 lacunar infarcts over 10 mm each, anycortical infarct over 10 mm, or any other clinically significant finding (e.g., anylesion that may account for their cognitive impairment, including but not limited tobrain tumor, severe white matter disease with a rating of 3 on the Fazekas scale forWM lesions ,arteriovenous malformation, cavernous hemangioma, or any infarct in astrategic subcortical location);
10. History of hypersensitivity to the treatment drugs;
11. Participate in other clinical study within the last 30 days;
12. Has metal (ferromagnetic) implants, or a cardiac pacemaker and other conditions thatcould not undergo MRI scan;
13. or other conditions that, in the investigator's opinion, could interfere with theanalyses of safety and efficacy in this study.