This is a two-part randomized, double-blind, placebo-controlled study.

This is a two-part randomized, double-blind, placebo-controlled study. The study comprises a SAD (Part 1) assessment which will include a food effect assessment that contributes data to inform a subsequent MAD (Part 2) dose-ranging study. Safety measurements will be collected throughout the study for all subjects. Blood samples will be collected to determine the PK parameters of SRP-3D (DA).

Inclusion Criteria:

1. Healthy male or female. Females must not be pregnant or breastfeeding.
2. Is between 18 and 55 years of age (inclusive).
3. Able to speak and understand English or Spanish.
4. Agrees to comply with testing procedures.
5. Has a body mass index (BMI) between 18.0 and 32.0 kg/m2 (inclusive).
6. The subject meets good health criteria.
7. Females of non-childbearing potential or agree to use birth control.
8. Male subjects must be surgically sterile or agree to the use birth control.
9. Agree to the confinement period and return for the outpatient visits.
10. Has vital signs at screening within appropriate ranges.

Exclusion Criteria:

1. History or presence of clinically significant diseases.
2. Abnormal diet 4 weeks preceding the first dose of study medication.
3. Received any investigational product in a clinical study.
4. Previously been administered IMP in this study.
5. Taking any prescribed or OTC drug.
6. Taking moderate or strong inhibitors/inducers of cytochrome P450.
7. History of hypersensitivity to acetaminophen or similar chemical entities.
8. Presence or history of allergy or blood or plasma donation.
9. Blood or plasma donation
10. Smokers and those who have smoked within the last 12 months.
11. Current users of e-cigarettes and nicotine replacement products.
12. Consumption of prohibited beverages or foods.
13. Prior history of substance abuse or treatment.
14. Regular alcohol consumption.
15. Positive alcohol urine test at screening or admission.
16. Is a female with a positive pregnancy test result.
17. Positive urine screen for drugs of abuse.
18. Positive test for hepititus B or C, or HIV.
19. Active infection, periodontal disease,. certain dental appliances.
20. Glucose-6-phosphate-dehydrogenase (G6PD) deficiency.
21. Significant serious skin disease.
22. Cohort 3 only: history of cholecystectomy or gall stones.
23. Have poor venous access that limits phlebotomy
24. Evidence of current SARS-CoV-2 infection
25. Clinically significant abnormal clinical chemistry, hematology or urinalysis.
26. Immediate family members of a study site or Sponsor employee.
27. Failure to satisfy the Investigator of fitness to participate.

Double-blind