Please select the arm or intervention descriptions that belong to the clinical trial below.
Title: A Phase IIb, Observer-blind, Randomised Controlled Trial to Assess the Immunogenicity and Protective Efficacy of Vi Conjugated (Vi-TCV) and Unconjugated (Vi-PS) Polysaccharide Vaccines in Preventing Typhoid Infection Compared to a Control Vaccine (Meningococcal ACWY), Using a Human Challenge Model of Typhoid Infection
Brief Summary: Using an established model of human typhoid infection, whereby healthy adults are deliberately exposed to typhoid-causing bacteria, the investigators will determine how effective a new typhoid conjugate vaccine (Vi-TCV) is in preventing infection. The new typhoid vaccine will be compared with a control vaccine (meningococcal ACWY). The protective effect of a currently used typhoid polysaccharide vaccine (Vi-PS) will also be studied and compared with the control vaccine using this model of typhoid infection.

A second component of this study will involve vaccinating 15-20 participants with Vi-PS. Serum will be obtained prior to vaccination and 4-6 weeks after vaccination. The post-vaccination serum will be pooled and used to create an anti-Vi IgG serum standard.


Options:
A: Arm Label: Vi-TCV; Type: EXPERIMENTAL; Interventions: Biological: Vi-TCV | Arm Label: Vi-PS Vaccine; Type: ACTIVE_COMPARATOR; Interventions: Biological: Vi-PS Vaccine | Arm Label: Control (Men ACWY); Type: OTHER; Interventions: Biological: Control (Men ACWY) | Intervention Type: BIOLOGICAL; Name: Vi-TCV; Assigned to Arm(s): Vi-TCV | Intervention Type: BIOLOGICAL; Name: Vi-PS Vaccine; Assigned to Arm(s): Vi-PS Vaccine | Intervention Type: BIOLOGICAL; Name: Control (Men ACWY); Assigned to Arm(s): Control (Men ACWY)
B: Arm Label: NVGH Vi-CRM197 conjugate vaccine 12.5 mcg; Type: EXPERIMENTAL; Interventions: Biological: NVGH Vi-CRM197 12.5 mcg | Arm Label: NVGH Vi-CRM197 conjugate vaccine 5 mcg; Type: EXPERIMENTAL; Interventions: Biological: NVGH Vi-CRM197 5.0 mcg | Arm Label: NVGH Vi-CRM197 conjugate vaccine 1.25 mcg; Type: EXPERIMENTAL; Interventions: Biological: NVGH Vi-CRM197 1.25 mcg | Arm Label: Typherix; Type: ACTIVE_COMPARATOR; Interventions: Biological: Vi-polysaccharide vaccine | Intervention Type: BIOLOGICAL; Name: NVGH Vi-CRM197 12.5 mcg; Assigned to Arm(s): NVGH Vi-CRM197 conjugate vaccine 12.5 mcg | Intervention Type: BIOLOGICAL; Name: NVGH Vi-CRM197 5.0 mcg; Assigned to Arm(s): NVGH Vi-CRM197 conjugate vaccine 5 mcg | Intervention Type: BIOLOGICAL; Name: NVGH Vi-CRM197 1.25 mcg; Assigned to Arm(s): NVGH Vi-CRM197 conjugate vaccine 1.25 mcg | Intervention Type: BIOLOGICAL; Name: Vi-polysaccharide vaccine; Assigned to Arm(s): Typherix
C: Arm Label: 1; Type: EXPERIMENTAL; Interventions: Biological: Typhoid Vi vaccine | Arm Label: 2; Type: ACTIVE_COMPARATOR; Interventions: Biological: Hepatitis A vaccine | Intervention Type: BIOLOGICAL; Name: Typhoid Vi vaccine; Assigned to Arm(s): 1 | Intervention Type: BIOLOGICAL; Name: Hepatitis A vaccine; Assigned to Arm(s): 2
D: Arm Label: Vi-CRM, Adults; Type: EXPERIMENTAL; Interventions: Biological: Vi-CRM197 vaccine | Arm Label: Vi-PS, Adults; Type: ACTIVE_COMPARATOR; Interventions: Biological: Vi Polysaccharide (PS) vaccine | Arm Label: Vi-CRM, Children; Type: EXPERIMENTAL; Interventions: Biological: Vi-CRM197 vaccine | Arm Label: Vi-PS, Children; Type: ACTIVE_COMPARATOR; Interventions: Biological: Vi Polysaccharide (PS) vaccine, Biological: Pneumococcal conjugate vaccine | Arm Label: Vi-CRM, Older infants; Type: EXPERIMENTAL; Interventions: Biological: Vi-CRM197 vaccine | Arm Label: PNC13, Older infants; Type: ACTIVE_COMPARATOR; Interventions: Biological: Pneumococcal conjugate vaccine | Arm Label: Vi-CRM, Infants; Type: EXPERIMENTAL; Interventions: Biological: Vi-CRM197 vaccine | Arm Label: PNC13, Infants; Type: ACTIVE_COMPARATOR; Interventions: Biological: Pneumococcal conjugate vaccine | Intervention Type: BIOLOGICAL; Name: Vi-CRM197 vaccine; Assigned to Arm(s): Vi-CRM, Adults, Vi-CRM, Children, Vi-CRM, Infants, Vi-CRM, Older infants | Intervention Type: BIOLOGICAL; Name: Vi Polysaccharide (PS) vaccine; Assigned to Arm(s): Vi-PS, Adults, Vi-PS, Children | Intervention Type: BIOLOGICAL; Name: Pneumococcal conjugate vaccine; Assigned to Arm(s): PNC13, Infants, PNC13, Older infants, Vi-PS, Children

Answer: A