Remdesivir

Remdesivir will be administered as a 200 mg intravenous loading dose on Day 1, followed by a 100 mg once-daily intravenous maintenance dose for the duration of the hospitalization up to a 10 days total course.
n=475
Drug: Remdesivir (The lyophilized formulation of Remdesivir is a preservative-free, white to off-white or yellow, lyophilized solid containing 100 mg of Remdesivir to be reconstituted with 19 mL of sterile water for injection and diluted into IV infusion fluids prior to IV infusion. Following reconstitution, each vial contains a 5 mg/mL Remdesivir concentrated solution with sufficient volume to allow withdrawal of 20 mL (100 mg of remdesivir). It is supplied as a sterile product in a single-use, 30 mL, Type 1 clear glass vial.)
Other: Standard of care (Standard of care)

Lopinavir/ritonavir (stopped on June 29, 2020)

Lopinavir/ritonavir (400 lopinavir mg/100 mg ritonavir) will be administered every 12 h for 14 days in tablet form. For patients who are unable to take medications by mouth, the lopinavir/ritonavir (400 lopinavir mg/100 mg ritonavir) will be administered as a 5-ml suspension every 12 h for 14 days via a pre-existing or newly placed nasogastric tube.
n=620
Drug: Lopinavir/ritonavir (The oral tablets of lopinavir/ritonavir contain 200 mg lopinavir, 50 mg ritonavir. They have a yellow colour, film-coated, ovaloid shape debossed with the "a" logo and the code KA. The oral solution for patients who cannot swallow is a light yellow to orange colored liquid containing 400 mg lopinavir and 100 mg ritonavir per 5 mL (80 mg lopinavir and 20 mg ritonavir per mL).)
Other: Standard of care (Standard of care)

Lopinavir/ritonavir plus Interferon ß-1a (stopped on June 29)

Lopinavir/ritonavir (400 lopinavir mg/100 mg ritonavir) will be administered every 12 h for 14 days in tablet form. For patients who are unable to take medications by mouth, the lopinavir/ritonavir (400 lopinavir mg/100 mg ritonavir) will be administered as a 5-ml suspension every 12 h for 14 days via a pre-existing or newly placed nasogastric tube.
Interferon ß1a will be administered subcutaneously at the dose of 44 µg for a total of 3 doses in 6 days (day 1, day 3, day 6).
n=620
Drug: Lopinavir/ritonavir (The oral tablets of lopinavir/ritonavir contain 200 mg lopinavir, 50 mg ritonavir. They have a yellow colour, film-coated, ovaloid shape debossed with the "a" logo and the code KA. The oral solution for patients who cannot swallow is a light yellow to orange colored liquid containing 400 mg lopinavir and 100 mg ritonavir per 5 mL (80 mg lopinavir and 20 mg ritonavir per mL).)
Drug: Interferon Beta-1A (IFN-ß-1a is supplied as a sterile solution containing no preservative available in a prefilled syringe. It will be provided as a single-dose prefilled graduated syringe with 44 µg per 0.5 mL. The liquid should be clear to slightly yellow. Do not use if the liquid is cloudy, discolored or contains particles. Use a different syringe.)
Other: Standard of care (Standard of care)

Hydroxychloroquine (stopped on May 24, 2020)

Hydroxychloroquine will be administered orally as a loading dose of 400 mg twice daily for one day followed by 400 mg once daily for 9 days. The loading dose of hydroxychloroquine through a nasogastric tube will be increased to 600 mg twice a day for one day, followed by a maintenance dose of 400 mg once a day for 9 days n=620
Drug: Hydroxychloroquine (Hydroxychloroquine is supplied as film-coated 200 mg tablets. Hydroxychloroquine sulfate tablets are presented as white or whitish, peanut-shaped, oblong or round film-coated tablets containing 200 mg of hydroxychloroquine sulfate (equivalent to 155 mg base).)
Other: Standard of care (Standard of care)

AZD7442

Participants randomized to the AZD7442 group will receive a total dose of 600 mg AZD7442 via a co-administered (300 mg AZD8895 and 300 mg AZD1061) single IV infusion on Day 1.
n=620
Other: Standard of care (Standard of care)
Drug: AZD7442 (AZD7442 will be supplied as separate vials of AZD8895 and AZD1061 containing 150 mg colorless to slightly yellow, clear to opalescent solutions for injection.)

Standard of care alone

Standard of care alone before March, 2021.
Other: Standard of care (Standard of care)

Standard of care with placebo

Standard of care with placebo since April, 2021 n=620
Other: Standard of care (Standard of care)
Other: Placebo (Since April, 2021, the placebo will be a 0.9% (w/v) NaCl solution for infusion also called saline. The placebo will be supplied as a single 10-mL, clear and colorless vial.)