The role of pre-existing cross-reactive antibodies in determining the efficacy of vaccination in humans: study protocol for a randomized controlled trial

Table 2 Study schema for study arms 1, 2 and 3

	Visit 1 screening (-21 to -1 days)	Visit 2 - first vaccination (day 0)		Visit 3 - second vaccination (+2 weeks from first vaccination)*		Visit 4 - third vaccination (+2 weeks from second vaccination)*
		Pre-vaccination	1 hour post-vaccination	Pre-vaccination	1 hour post-vaccination	Pre-vaccination	1 hour post-vaccination
Inform consent	×
Medical history and demographics	×
Physical examination	×	x	x	x	x		×
Vital signs^a	×	×	×	×	×	×	×
Hematology labs^b	×
Chemistry labs (liver, renal panel^c)	×
Dengue immunoglobulinG^d	×
Urine pregnancy test^e	×	×
Adverse events^f	×	×		×		×
Concomitant medications	×	×		×		×
Blood sampling in relation to YF17D vaccination						×^g

*Window period: for second vaccination is +2 weeks (vaccination cannot be done earlier); for third vaccination (group 1, 2, 3) is +2 weeks (vaccination cannot be done earlier). ^aVital signs include temperature (oral and tympanic allowed), blood pressure, pulse rate, and respiratory rate. ^bHematology labs include hemoglobin, red blood cell, white blood cell, hematocrit, platelet count, neutrophil, lymphocyte, monocyte, eosinophil, basophil. ^cLiver panel includes total protein, albumin, total bilirubin, alkaline phosphatase, ALT alanine transaminase, AST aspartate transaminase, gamma-glutamyl transpeptidase. Renal panel includes urea, sodium, potassium, chloride, bicarbonate, creatinine. ^dDengue immunoglobulin G will be tested by enzyme-linked immunosorbent assay. ^eFor females only. ^fClinical Trial Certificate Adverse Events version 4.0 will be used for grading. ^gFor third vaccination, pre-dose blood sample can be taken any time before dosing. YF, yellow fever.

ISSN: 1745-6215