A Randomised, Multi-centre, Double-blind, Phase 3 Study to Observe the Effectiveness, Safety and Tolerability of Molnupiravir Compared to Placebo Administered Orally to High-risk Adult Outpatients With Mild COVID-19 Receiving Local Standard of Care in South Africa

Inclusion Criteria:

1. Able and willing to provide written or electronic informed consent prior to anystudy-specific procedure.

2. Age ≥50 at the time of signing the informed consent form.

3. Women of reproductive potential must have a negative pregnancy test at screening andbe using a highly effective method of contraception. Highly effective methods ofcontraception

4. A male participant must wear a condom when engaging in any activity that allows forpassage of ejaculate to another while taking the investigational product. Maleparticipants should also be advised of the benefit for a female partner to use ahighly effective method of contraception as condom may break or leak.

5. Self-reported symptoms of COVID-19 with onset no more than five days prior toscreening informed consent including at least one of, fever or chills, cough, sorethroat, rhinorrhoea or rhinitis or sinusitis, shortness of breath, headache,myalgia, new onset anosmia or ageusia, nausea, diarrhoea, or extreme fatigue, orother symptoms recognized in local and international guidelines as typical of mildCOVID-19.

6. SARS-CoV-2 infection confirmed through a positive LumiraDx rapid antigen test on theday of screening or a positive RT-PCR within two days prior to screening.

7. Participant is at high risk for progression to severe COVID-19, this defined aseither:

8. Age ≥50 with at least one of the following background or medical conditions:diabetes mellitus, obesity (BMI 30 kg/m2), hypertension, HIV, active orprevious TB.

9. Age ≥65

10. Participant agrees to comply with study procedures, including the completion of adaily diary for 10 days from the time of enrolment, and to be available for studycontacts and visits.

• Exclusion Criteria:

1. Pregnant or breastfeeding women, or women planning/desiring to become pregnantduring the 28 days following enrolment into the study.

2. Duration of self-reported symptoms of COVID-19 for more than five days prior toscreening.

3. Signs of respiratory distress or severe disease prior to enrolment, including:

4. Inability/unlikely to be in the study area for the duration of the 28-day follow-upperiod.

5. Inability to tolerate oral medications.

6. Any surgical or medical condition which might significantly alter the absorption,distribution, metabolism, or excretion of drugs, or which may jeopardize the safetyof the patient or the objectives of the study. The Investigator should make thisdetermination in consideration of the volunteer's medical history.

7. The volunteer is assessed to be clinically unstable in the Investigator's opinion.

8. Participation in another investigational study involving an investigational productwithin 30 days, or 5 half-lives, whichever is longer, prior to screening.

9. Personnel (e.g., investigator, sub-investigator, research assistant, pharmacist,study coordinator or anyone mentioned in the delegation log) directly involved inthe conduct of the study.

10. Any physical, mental, or social condition, drug/alcohol use, history of illness orlaboratory abnormality that, in the Investigator's judgment, might jeopardise thesafety of the patient in the context of this study, or might interfere with studyprocedures or the ability of the subject to adhere to and complete the study. TheInvestigator should make this determination in consideration of the volunteer'smedical history.