⁃ Adults (≥18 years) with laboratory-confirmed\* SARS-CoV-2 infection (PCR)

⁃ Ability to provide informed consent signed by study patient or legally acceptable representative

⁃ Women of childbearing potential (WOCBP) and male patients who are sexually active with WOCBP must agree to use a highly effective method of contraception (as outlined in the protocol) from the first administration of trial treatment, throughout trial treatment and for the duration outlined in the candidate-specific trial protocol after the last dose of trial treatment

∙ If any CSTs are included in the community setting, the CST protocol will clarify whether patients with suspected SARS-CoV-2 infection are also eligible.

• Standard additional criteria that may be applied per CST protocol:

• Group A (severe disease) 4a. Patients with clinical status of Grades 4 (hospitalised, oxygen by mask or nasal prongs), 5 (hospitalised, on non-invasive ventilation, or high flow oxygen), 6 (hospitalised, intubation and mechanical ventilation) or 7 (ventilation and additional organ support - pressors, renal replacement therapy (RRT), extracorporeal membrane oxygenation (ECMO)), as defined by the WHO clinical severity score, 9-point ordinal scale.

• 1\. Male or female ≥ 60 years old or ≥50 years old with at least one well controlled comorbidity: cardiovascular disease, chronic lung disease (e.g. COPD, or pulmonary hypertension), immune deficiency (taking the equivalent of 20 mg prednisone daily, chemotherapy, or immune modulating biologic therapies), diabetes (treated with insulin or oral medications), BMI≥30, or hypertension requiring medication with laboratory confirmed SARS-CoV-2 infection (PCR) .

• 3\. Women of childbearing potential (WOCBP) and male patients who are sexually active with WOCBP must agree to use two effective methods of contraception, one of which should be highly effective (as outlined in the protocol). For women, from the first administration of trial treatment, throughout trial and up to 50 days after the last follow up visit (50 days after day 29) and for men with female partners of child bearing potential, from the first administration until 100 days after last follow up visit (100 days after day 29).

• 4\. Group B (mild-moderate disease): Ambulant with the following characteristics peripheral capillary oxygen saturation (SpO2) \>94% RA (NB this differs to the Master Protocol which also includes hospitalised patients in this group).

• Additional criteria specific to this candidate are:

• 5\. Has signs or symptoms of COVID-19 that began within 5 days of the planned first dose of study drug.

• 6\. Is in generally good health (except for current respiratory infection) and is free of uncontrolled chronic conditions.

• 7\. Is willing and able to comply with all study procedures and attending clinic visits through the 4th week.

• 8\. Has someone, aged ≥ 16 living in the same household during the dosing period.

⁃ Group A (severe disease). Patients with clinical status of Grades 5 (hospitalised, oxygen by mask or nasal prongs), 6 (hospitalised, on non-invasive ventilation, or high flow oxygen as defined by the WHO Clinical Progression Scale (WHO, 2020)).

⁃ Less than or equal to 14 days from onset of COVID-19 symptoms

⁃ For the purpose of CST-8, criteria 1 has been amended from the Master Protocol to:

⁃ Adults (≥18 years) outpatients positive lateral flow test at screening or baseline Day 1, who are within 5 days of symptom onset prior to the planned first dose of study drug.

⁃ Criteria 3 has been amended from the Master Protocol to:

• Women of childbearing potential (WOCBP) and male participants who are sexually active with WOCBP must agree to use a highly effective method of contraception (as outlined in section 5.5 of the Master Protocol) for the duration of the treatment and for six weeks following the last dose.

• Additional criteria specific to CST-8 are:

• Initial onset of COVID-19 signs/symptoms within 5 days prior to the day of randomisation and at least 1 of the current specified COVID-19 signs/symptoms (listed on the NHS website) present on the day of randomisation

• Is willing and able to comply with all study procedures and attending clinic visits

• For the purpose of CST-9a, criteria 1 has been amended from the Master Protocol to:

⁃ Adults (\>/= 18 years of age) with a positive SARS-CoV-2 lateral flow test on screening or Day 1, who are at high risk (as defined in UK DHSC criteria) of progressing to severe COVID-19 disease, within 3 days of symptom onset, with at least one symptom of COVID-19 infection present on the day of randomization and are with mild- moderate disease severity at enrolment.

⁃ Criterion 2 has been amended from the Master Protocol to:

⁃ Ability to provide informed consent signed by trial participant or legally acceptable representative and are willing and able to comply with all trial procedures and attending clinic visits

⁃ Criterion 3 has been amended from the Master Protocol to:

⁃ Women of childbearing potential (WOCBP) and male participants who are sexually active with WOCBP must agree to use two effective methods of contraception, one of which must be highly effective for the duration of the treatment and for 90 Days following the last dose

• Master Protocol Exclusion Criteria:

⁃ Alanine aminotransferase (ALT) and/or aspartate aminotransferase (AST) \>5 times the upper limit of normal (ULN)

⁃ Stage 4 severe chronic kidney disease or requiring dialysis (i.e., estimated glomerular filtration rate \<30 mL/min/1.73 m\^2)

⁃ Pregnant or breast feeding

⁃ Anticipated transfer to another hospital which is not a study site within 72 hours

⁃ Allergy to any study medication

⁃ Patients taking other prohibited drugs (as outline in CST protocol) within 30 days or 5 times the half-life (whichever is longer) of enrolment

⁃ Patients participating in another CTIMP trial

⁃ N.B. The CST protocol exclusion criteria will take precedence over the master protocol exclusion criteria.

⁃ CST-2 Exclusion Criteria:

⁃ Additional criteria specific to this candidate are:

⁃ Has a febrile respiratory illness that includes signs of pneumonia, or requires hospitalization, oxygenation, mechanical ventilation, or other supportive modalities.

⁃ Has a platelet count less than 50x10\^9/L, or lymphocytes less than 0.2x10\^9/L, haemoglobin less than 10 g/dL, or has a disorder of the hematologic system including anaemic disorder or other blood dyscrasia, cancer of the hematologic system, history of bone marrow transplant, or other significant hematologic disease at screening.

‣ Is experiencing adverse events or laboratory abnormalities that are Grade 3 or above based on the CTCAE scale.

‣ Has clinically significant liver dysfunction or renal impairment.

‣ Has history of Hepatitis C infection or concurrent bacterial pneumonia.

‣ Has received an experimental agent (vaccine, drug, biologic, device, blood product, or medication) within 30 days prior to the first dose of study drug.

‣ In the opinion of the investigator, has significant end-organ disease as a result of relevant comorbidities: chronic kidney disease, congestive heart failure, peripheral vascular disease including diabetic ulcers.

‣ Has a SaO2\<95% by oximetry or has lung disease that requires supplemental oxygen.

‣ Has any condition that would, in the opinion of the investigator, put the patient at increased risk for participation in a clinical study.

• CST-8 Exclusion Criteria:

• For the purpose of the combination CST8 candidate-specific trial the following exclusion criteria also apply:

⁃ Swallowing difficulties

⁃ Known medical history of active liver disease

⁃ Receiving dialysis or have known moderate to severe renal impairments (defined as CKD stage 4 or 5 or current acute kidney injury or most recent eGFR in the past 6 months \<30 ml/min/1.73m2)

⁃ Currently taking Paxlovid® or molnupiravir at time of screening

⁃ Oxygen saturation of \<92% on room air, or on their standard home oxygen supplementation

⁃ Taking a drug which would put subject at unacceptable risk due to interaction or is contraindicated as per SPC for each IMP

• CST-9a Exclusion Criteria: