Safety of Bryostatin in Patients With MS

Inclusion 1. Written informed consent signed by participant 2. English-speaking 3. Hospital Anxiety and Depression Scale \<11 4. Male and female participants, 18-65 years of age inclusive 5. Established diagnosis of MS, as defined by the 2017 revision of McDonald Diagnostic Criteria (any form of MS). A diagnosis of MS must be confirmed at the time of the screening visit. 6. Processing Speed Test (PST) z-score between -1.0 and -2.5 7. EDSS between 0.0 and 7.0, inclusive. 8. Adequate vision and motor function to participate in assessment procedures 9. Participants must be off of a DMT or on a stable dose of a DMT for at least 1 year prior to entry into the study, and the dose should not change during the study unless a change is required by a clinically significant change in the participant's status. 10. Females participating in the study must meet one the following criteria: 1. Surgically sterilized (e.g., hysterectomy, bilateral oophorectomy or tubal ligation) for at least 6 months or postmenopausal (postmenopausal females must have no menstrual bleeding for at least 1 year) or 2. If not postmenopausal, agree to use a double method of contraception, one of which is a barrier method (e.g., intrauterine device plus condom, spermicidal gel plus condom) 30 days prior to dosing until 30 days after last dose and have negative human chorionic gonadotropin (β-hCG) test for pregnancy at screening. Contraception methods resulting in an overall failure rate of \<1 % per year are required for women of childbearing potential. 11. Males who have not had a vasectomy must use appropriate contraception methods (barrier or abstinence) from 30 days prior to dosing until 30 days after last dose 12. Participants should be in reasonably good health over the last 6 months and any chronic disease should be stable. Exclusion 1. Evidence of significant CNS vascular disease on previous neuroimaging, including but not limited to cortical stroke, multiple infarcts, localized single infarcts in the thalamus, angular gyrus, multiple lacunar infarcts, or extensive white matter injury 2. Clinically significant neurologic disease or condition other than MS, such as cerebral tumor, chronic subdural fluid collections, Huntington's Disease, Parkinson's Disease, normal pressure hydrocephalus, or any other diagnosis that could interfere with assessment of safety and efficacy 3. Previous history of seizures or seizure disorders. 4. Evidence of clinically significant unstable cardiovascular, pulmonary, renal, hepatic, gastrointestinal, neurologic, or metabolic disease within the 6 months prior to enrollment. If there is a history of cancer, the participant should be clear of cancer for at least 2 years prior to screening. More recent history of basal cell or squamous cell carcinoma and melanoma in situ (Stage 0) may be acceptable after review by the Medical Monitor. 5. Estimated Glomerular Filtration Rate (eGFR) of \<45ml/min 6. Poorly controlled diabetes (at the discretion of the Principal Investigator) 7. Use of vitamin E \> 400 International Units (IU) per day within 14 days prior to screening 8. Use of valproic acid and/or lithium within 14 days prior to screening 9. Use of carbamazepine within 7 days prior to screening 10. Use of teriflunomide within 90 days prior to screening 11. Use of dalfampridine within 7 days of screening 12. Current use of acetaminophen, ciprofloxacin, and/or trimethoprim/sulfamethoxazole 13. Use of any potent or moderate inhibitor or inducer of CYP3A4, CYP2C8, or CYP2C9. Concomitant medicines will be examined on a case-by-case basis against the Flockhart Table by study investigator, and if needed, the Medical Monitor, to determine allowability 14. Current use of St. John's Wort, within 2 weeks prior to screening 15. Consumption of grapefruit juice from screening until end of study 16. At the discretion of the PI, any medical or psychiatric condition that is unstable or may require the initiation of additional medication or surgical intervention during the course of the study 17. Any screening laboratory values outside the laboratory reference ranges that are deemed clinically significant by the PI 18. Use of an investigational drug within 30 days prior to screening 19. Suicidality defined as active suicidal thoughts during the 6 months prior to screening or at Baseline \[SBQ-R\], or history of suicide attempt in previous 2 years, or at serious suicide risk in study neurologist or PI's judgment 20. Major psychiatric illness such as currently uncontrolled major depression according to Diagnostic and Statistical Manual of Mental Disorders, 5th Edition4, current or past diagnosis of bipolar disorder, schizophrenia, or any other psychiatric disorder that might interfere with the assessments of safety or efficacy at the discretion of the PI 21. Diagnosis of alcohol or drug abuse within the last 2 years 22. History of prolonged QT or prolonged QT on screening ECG \[QT correction with Bazett formula (QTcB) or QT correction by Fridericia (QTcF)\>499 per central reader\]5 23. Acute or poorly controlled medical illness: blood pressure \>180 mmHg systolic or 100 mmHg diastolic; myocardial infarction within 6 months; uncompensated congestive heart failure \[New York Heart Association (NYHA) Class III or IV\] 24. Known to be seropositive for Hepatitis B or C, unless successful curative treatment for Hepatitis C (e.g., Harvoni) has been received, and there is documentation that there is no Hepatitis B/C virus detected 3 months after completion of treatment 25. Known to be seropositive for human immunodeficiency virus (HIV) 26. Pregnancy or breastfeeding during the study. A β-hCG serum pregnancy test will be performed at Screening for female patients of child-bearing potential. 27. Aspartate Amino Transferase (AST) or Alanine Aminotransferase (ALT) \>3x upper limit of normal (ULN) and total bilirubin \>2x ULN or International Normalized Ratio (INR) \>1.5 28. History of significant bleeding disorders. 29. Moderate baseline thrombocytopenia (platelets \<100K/uL). 30. Elevated INR (\>2.0). 31. Prior exposure to bryostatin, or known sensitivity to bryostatin or any ingredient in the study drug 32. Any other concurrent medical condition, which in the opinion of the PI makes the participant unsuitable for the clinical study