Fig. 2: Overview of reported COVID-19 vaccine prime-boost schemes and clinical efficacies.
From: COVID-19 vaccines in patients with cancer: immunogenicity, efficacy and safety
a | Reported prime boost regimens and clinical efficacy in individuals without cancer. ‘Efficacy of boost’ data are from refs34,251. b | Reported prime boost regimens and clinical efficacy in patients with cancer. Primary vaccination (prime) usually consists of two vaccine doses (except for Ad26.COV2.S) which are administered at intervals of variable length from 21 days to 3 months. Vaccine efficacy (VE) in these studies is defined as the prevention of symptomatic COVID-19. The strength of serological responses is summarized with arrows indicating a moderate (one arrow) or strong (two arrows) response. An additional booster dose is administered 2 to 6 months after completion of prime vaccination. Boosts can either be homologous (same vaccine type) or heterologous (different vaccine type) and consist of one dose. Additional booster doses either designed against wild-type or with variant-specific designs are expected to become available in the next months (and in some countries are already available for patients with a compromised immune system), although the clinical efficacy and the optimal regimens need to be determined. aSlightly varying responses reported from two different studies.
