Efficacy and Safety of Flos Gossypii Flavonoids Tablet in the Treatment of Alzheimer's Disease

Inclusion Criteria:

1. Age 50 to 85 years old (including 50 and 85 years old), male or female;

2. Meet the diagnostic criteria of "likely ad dementia" of the National Institute onaging Alzheimer's disease association (NIA-AA) (2011);

3. The subjects are primary school graduates / graduates and above, and have theability to complete the cognitive ability test and other tests specified in theprogram;

4. Memory loss lasted for at least 6 months and tended to worsen gradually;

5. Subjects with mild or moderate illness: 11 ≤ MMSE ≤ 26;

6. Total score of Clinical Dementia Rating Scale (CDR): Mild dementia: CDR = 1.0; Moderate dementia: CDR = 2.0;

7. The total score of Hachinski scale(HIS) ≤ 4;

8. The total score of Hamilton Depression Scale (HAMD 17 item version) is ≤ 10;

9. There was no obvious positive sign in nervous system examination;

10. Coronal scanning of head MRI in screening stage: the MTA grade of medial temporallobe atrophy visual assessment scale is grade 2 or higher, and the signal changes ofT2 FLAIR sequence in coronal position of hippocampus. If the subject can provide thehead MRI film that meets the requirements within 1 month before screening, it can beused as the basis for enrollment without repeated shooting; If the researcher cannotjudge whether the subject's condition has changed, the coronal MRI scan of the headbefore enrollment can be added;

11. The subjects should have stable and reliable caregivers, who will take care of themat least 3 days a week and at least 2 hours a day. The caregivers will accompany thesubjects to participate in the whole process of the study. Caregivers must accompanythe subjects to the study visit and assist the investigator in completing theNeuropsychiatric Inventory (NPI), Alzheimer's Disease Collaborative Study-Ability ofDaily Living Scale (ADCS-ADL), and Clinician Interview Based Impression of Severity (CIBIC -plus), and other scale scores;

12. Agree to participate and sign the informed consent form by the legal guardian. Dueto the subject's limited cognitive ability and other reasons, the subject'ssignature is allowed to be left blank, and the reason is explained. In addition, thelegal guardian shall sign the reason statement, and the legal guardian shall signthe informed consent;

13. Meet the criteria the traditional Chinese medicine of AD which is characterized bythe syndrome of insufficient sea of marrow/cerebral collateral stasis. According tothe Dementia Syndrome Classification Scale (SDSD), one of the syndromes ofinsufficient sea of marrow/cerebral collateral stasis can be met.

Exclusion Criteria:

1. During screening, MRI examination showed significant focal lesions, fulfilling oneof the following conditions:

① There were more than 2 infarcts with diameter > 2 cm at any site;

② MRI examination showed that there were infarcts with arbitrary diameter in keyparts (such as thalamus, hippocampus, entorhinal cortex, paraolfactory cortex,angular gyrus, cortex and other subcortical gray matter nuclei);

③ Fazekas scale grade of white matter lesions > 2;

④ There are other imaging evidences that do not support mild and moderate AD;

2. Dementia caused by other reasons: vascular dementia, central nervous systeminfection, Creutzfeldt Jakob disease, Huntington's disease, Parkinson's disease,Lewy body dementia, traumatic dementia, other physical and chemical factors (such asdrug poisoning, alcoholism, carbon monoxide poisoning, etc.), important physicaldiseases (such as hepatic encephalopathy, pulmonary encephalopathy, etc.),intracranial space occupying lesions (such as subdural hematoma, brain tumor),endocrine disorders (such as thyroid disease, parathyroid disease), and vitamin B12,folic acid deficiency or any other known cause;

3. Have suffered from central nervous system diseases (including stroke, opticneuromyelitis, epilepsy, etc.);

4. Subjects who were diagnosed with psychiatric disorders according to DSM-V criteria,including schizophrenia or other mental diseases, bipolar disorder, severedepression or delirium;

5. Abnormal laboratory indexes: liver function (ALT and AST) exceeded 1.5×ULN, renalfunction (CR) exceeded 1.5×ULN, and creatine kinase exceeded 2×ULN;

6. Untreated hypertensive and hypotensive subjects at screening, or hypertensivesubjects with uncontrolled hypertension after treatment; subjects with good bloodpressure control after treatment can be determined by the investigator to besuitable for inclusion in this study;

7. Within 1 month of the screening visit, the subject has new or ongoing unstable orserious heart, lung, liver, kidney and hematopoietic diseases according to thejudgment of the researcher, and does not meet the conditions for clinical research;

8. Clinically, people with significant allergic reaction history, especially drugallergy history, or known allergy to this product and its excipients;

9. Dyspepsia, esophageal reflux, gastric bleeding or peptic ulcer disease, frequentheartburn (≥ once a week) or any surgical operation that may affect drug absorption (such as partial / total gastrectomy, partial / total small bowel resection andcholecystectomy) within 6 months before screening;

10. Alcohol or drug abusers;

11. Human immunodeficiency virus antibody (ant HIV) and Treponema pallidum antibody (antTP) are positive;

12. Those who are currently using and cannot stop using drugs for Alzheimer's disease;

13. Screening for cholinesterase inhibitors, N-methyl-D-aspartate receptor antagonists (NMDA antagonists), mental retardants, antiparkinsonian drugs and opioid analgesicstaken within 1 month before the visit;

14. There are uncorrectable visual and auditory disorders, and the neuropsychologicaltest and scale evaluation cannot be completed;

15. Female subjects with positive pregnancy test or lactation and subjects unable totake effective contraceptive measures or have family planning;

16. Participated in other clinical trials within 3 months before the screening visit;

17. There are other situations that the researcher believes are not suitable toparticipate in this study.