Cumulative incidence and HRs for breakthrough infection in patients with MM or MGUS. (A) Cumulative incidence curves of any breakthrough SARS-COV-2 infection by disease state shown using time zero as 14 days after the day of second dose of vaccination. CIs were calculated by bootstrapping. The number at risk are also shown. (B) HRs for infection separated by disease state and COVID severity. Hazards are calculated separately for risk of any breakthrough infection and risk of severe breakthrough infection relative to matched controls. All hazards were calculated using Fine-Gray competing risk regression with the competing risk of death.