Study: NCT04324606

Intervention type: BIOLOGICAL
Group type: EXPERIMENTAL
Intervention: ChAdOx1 nCoV-19 full boost
Description: A single dose of 5x10\^10vp of ChAdOx1 nCoV-19 followed by a boost dose of 5x10\^10vp of ChAdOx1 nCoV-19

Intervention type: BIOLOGICAL
Group type: EXPERIMENTAL
Intervention: ChAdOx1 nCoV-19 half boost
Description: A single dose of 5x10\^10vp of ChAdOx1 nCoV-19 followed by a boost dose of 2.5x10\^10vp of ChAdOx1 nCoV-19

Intervention type: BIOLOGICAL
Group type: ACTIVE_COMPARATOR
Intervention: MenACWY boost
Description: A standard dose of MenACWY followed by a boost dose of MenACWY

Intervention type: BIOLOGICAL
Group type: ACTIVE_COMPARATOR
Intervention: MenACWY boost
Description: A standard dose of MenACWY followed by a boost dose of MenACWY

Intervention type: BIOLOGICAL
Group type: ACTIVE_COMPARATOR
Intervention: MenACWY boost
Description: A standard dose of MenACWY followed by a boost dose of MenACWY

Intervention type: BIOLOGICAL
Group type: EXPERIMENTAL
Intervention: MenACWY boost
Description: A standard dose of MenACWY followed by a boost dose of MenACWY

Intervention type: DRUG
Group type: EXPERIMENTAL
Intervention: Paracetamol
Description: 1g every 6 hours for 24 hours

Intervention type: DRUG
Group type: ACTIVE_COMPARATOR
Intervention: Paracetamol
Description: 1g every 6 hours for 24 hours

Intervention type: BIOLOGICAL
Group type: EXPERIMENTAL
Intervention: ChAdOx1 nCoV-19 0.5mL boost
Description: A single dose of 5x10\^10vp of ChAdOx1 nCoV-19 followed by a boost dose of ChAdOx1 nCoV-19 0.5mL (3.5-6.5x10\^10vp)

Intervention type: BIOLOGICAL
Group type: EXPERIMENTAL
Intervention: ChAdOx1 nCoV-19 0.5mL boost
Description: A single dose of 5x10\^10vp of ChAdOx1 nCoV-19 followed by a boost dose of ChAdOx1 nCoV-19 0.5mL (3.5-6.5x10\^10vp)

Intervention type: BIOLOGICAL
Group type: EXPERIMENTAL
Intervention: ChAdOx1 nCoV-19 0.5mL (3.5-6.5x10^10vp) late vaccine (LV)
Description: A dose of ChAdOx1 nCoV-19 0.5mL (3.5-6.5x10\^10vp) 9 months after receiving a single or double dose of 5x10\^10vp of ChAdOx1 nCoV-19

Intervention type: BIOLOGICAL
Group type: EXPERIMENTAL
Intervention: ChAdOx1 nCoV-19 0.5mL (3.5-6.5x10^10vp) late vaccine (LV)
Description: A dose of ChAdOx1 nCoV-19 0.5mL (3.5-6.5x10\^10vp) 9 months after receiving a single or double dose of 5x10\^10vp of ChAdOx1 nCoV-19

Intervention type: BIOLOGICAL
Group type: EXPERIMENTAL
Intervention: ChAdOx1 nCoV-19 0.5mL (3.5-6.5x10^10vp) late vaccine (LV)
Description: A dose of ChAdOx1 nCoV-19 0.5mL (3.5-6.5x10\^10vp) 9 months after receiving a single or double dose of 5x10\^10vp of ChAdOx1 nCoV-19

Intervention type: BIOLOGICAL
Group type: EXPERIMENTAL
Intervention: ChAdOx1 nCoV-19 0.5mL (3.5-6.5x10^10vp) late vaccine two (LVT)
Description: A dose of ChAdOx1 nCoV-19 0.5mL (3.5-6.5x10\^10vp) 9 months after receiving a single or double dose of MenACWY, then a boost 4-12 weeks later

Intervention type: BIOLOGICAL
Group type: EXPERIMENTAL
Intervention: ChAdOx1 nCoV-19 0.5mL (3.5-6.5x10^10vp) late vaccine two (LVT)
Description: A dose of ChAdOx1 nCoV-19 0.5mL (3.5-6.5x10\^10vp) 9 months after receiving a single or double dose of MenACWY, then a boost 4-12 weeks later