Eligibility Criteria:
Inclusion Criteria:
1. Prior diagnosis of mild-to-severe cognitive impairment or probable AD according to the National Institute on Aging and the Alzheimer's Association guidelines by a qualified health practitioner;
2. History of cognitive and functional decline over at least 1 year that is either documented in medical records or by history from an informant who knows the patient well;
3. Male or female, age 50 to 85 years (inclusive) at the Screening Visit;
4. Patient must be ambulatory and reside with a reliable, competent adult (study partner) who may or may not also be the patient's legally authorized representative (LAR) for informed consent;
5. Patient must be able to swallow the study medication (without any alteration to the tablet like crushing, cutting in half, or dissolving in a liquid);
6. Body weight at screening is ≥40kg;
7. CDR-SB of 3.0 or higher at Screening Visit;
8. MMSE-2 ≥8 and≤24 at the Screening Visit;
9. Patient must be able to understand the nature of the study and have the opportunity to have any questions answered and provide their consent. In the absence of patient's ability to provide informed consent, the informed consent must be obtained from the patient's Legally Authorized Representative (LAR);
10. For patients receiving an anticholinesterase inhibitor, memantine, or herbal medication for AD, the dose must have been stable for at least 3 months prior to the Screening Visit, and patient must agree to maintain this dose for the duration of the study;
11. Patients currently treated with a statin must agree to stop their statin therapy for the duration of treatment (180 days);
12. Creatinine Clearance \>30 mL/min at Screening;
13. Negative HIV and HCV test at Screening;
14. Complete blood count (CBC), blood chemistry, serum cholesterol, triglycerides, thyroid-stimulating hormone (TSH), and urinalysis, within normal reference ranges or not clinically significant as assessed by the Investigator at Screening;
15. Physical examination, vital signs, and ECG within normal ranges or not clinically significant as assessed by the Investigator at Screening;
16. Female patients may participate if they meet 1 of the following criteria:
1. Surgically sterile (e.g., hysterectomy, bilateral salpingectomy, bilateral oophorectomy), or
2. Post-menopausal, defined as
3. Permanent cessation of menstruation for ≥12 months without an alternative medical cause (regardless of follicle-stimulating hormone \[FSH\] value) at the Screening Visit, or
4. Cessation of menstruation for \<12 months and FSH \>40 mIU/mL at the Screening Visit.
Note: Patients with persistent menses due to hormonal therapy may participate if a urine pregnancy test (UPT) at the Screening Visit is negative and they agree to continued testing at every study visit.
17. Male patients must agree to use a barrier method of contraception and refrain from donating sperm for the duration of their participation in the study and for 2 months thereafter.
Exclusion Criteria:
1. Patient has had a myocardial infarction, unstable angina, stroke, transient ischemic attack or required intervention for any of these conditions (e.g., coronary artery bypass graft, percutaneous coronary intervention via cardiac catheterization, thrombolytic therapy) within 6 months of the Screening Visit;
2. Has other neurological disorders, including vascular dementia, Parkinson's disease, frontotemporal dementia, Huntington's disease, amyotrophic lateral sclerosis, multiple sclerosis, progressive supranuclear palsy, neurosyphilis, dementia with Lewy bodies, other types of dementia, mental retardation, hypoxic cerebral damage, and cognitive impairment from head trauma;
3. Scheduled or anticipates vaccination with a live vaccine during the study;
4. Current use of a cannabidiol or derivative;
5. Current use of digoxin;
6. Acute or chronic liver disease;
7. AST \>1.5 times the Upper Limit of Normal
8. ALT \> 1.5 times the Upper Limit of Normal
9. Schizophrenia, bipolar disorder, suicidal ideation, major depression, or delirium; Note: Stable (\>2 years) treated depression without suicidal ideation is acceptable;
10. Current therapy with a tetracycline;
11. Current therapy with sirolimus or a rapalog macrolide antibiotic;
12. Known allergies to any of the active drugs: tetracycline antibiotics, rapalog macrolide antibiotics, or statin therapies;
13. Treatment with another investigational drug, device, or intervention within 30 days prior to the Screening Visit;