NCT04019444

Dosage-Escalation Study of the Safety and Immunogenicity of a Novel Rabies Vaccine ChAd155-RG vs. the Comparator RABAVERT Vaccine in Healthy Adult Subjects

A Phase 1, Dosage-Escalation Study of the Safety and Immunogenicity of a Novel Rabies Vaccine ChAd155-RG vs. the Comparator RABAVERT Vaccine in Healthy Adult Subjects

• Status: Completed
• Phase: Phase 1
• Study type: Interventional
• Enrollment: 50 (actual)
• Sponsor: National Institute of Allergy and Infectious Diseases (NIAID) · NIH
• Sex: All
• Age: 18 Years – 49 Years
• Healthy volunteers: Accepted

Summary

This is a single-center, observer-blinded, dosage-escalation trial to evaluate the safety, tolerability, reactogenicity, and immunogenicity of ChAd155-RG compared with RABAVERT in rabies virus-naïve healthy male and non-pregnant female adult subjects ages 18-49. There are 4 dose groups: Group A will receive ChAd155-RG at the lower dosage (5x1010vp) on Day 1, then placebo injections on Days 8, 15, and 22; Group B will receive ChAd155-RG at the higher dosage (1x1011vp) on Day 1, then placebo injections on Days 8, 15, and 22; Group C will receive ChAd155-RG at the higher dosage (1x1011vp) on Days 1 and 15, and placebo injections on Days 8 and 22; Group D will receive RABAVERT at the standard dose (1 mL) on Days 1, 8, and 22, and a placebo injection on Day 15. Since this is a dosage-escalation study, sentinel subjects will be used at each dosage level before non-sentinel subjects will be enrolled. The study will be conducted at Emory University Vaccine and Treatment Evaluation Unit (VTEU). This trial is expected to take approximately 48 months to complete. The duration of each subject's participation is approximately 13 months, from recruitment through the last study visit. The primary objectives of this study are: 1) Assessment of the safety, tolerability, and reactogenicity of one dose of ChAd155-RG at 5x1010vp per dose, or one or two doses of ChAd155-RG at 1x1011vp per dose; 2) Comparison of the safety, tolerability, and reactogenicity of one or two doses of ChAd155-RG, with three doses of RABAVERT.

Detailed description

This is a single-center, observer-blinded, Phase 1, dosage-escalation trial to evaluate the safety, tolerability, reactogenicity, and immunogenicity of ChAd155-RG compared with RABAVERT in rabies virus-naïve healthy male and non-pregnant female adult subjects ages 18-49. Subjects who have never received a licensed or investigational rabies virus vaccine, or an Ad-based investigational vaccine, and who have never been exposed to a rabid animal will be eligible for enrollment. There are 4 dose groups: Group A will receive ChAd155-RG at the lower dosage (5x1010vp) on Day 1, then placebo injections on Days 8, 15, and 22; Group B will receive ChAd155-RG at the higher dosage (1x1011vp) on Day 1, then placebo injections on Days 8, 15, and 22; Group C will receive ChAd155-RG at the higher dosage (1x1011vp) on Days 1 and 15, and placebo injections on Days 8 and 22; Group D will receive RABAVERT at the standard dose (1 mL) on Days 1, 8, and 22, and a placebo injection on Day 15. Since this is a dosage-escalation study, sentinel subjects will be used at each dosage level before non-sentinel subjects will be enrolled. The SMC will review the available safety, reactogenicity, AE, and lab data of all the sentinel subjects, and will decide if the remaining non-sentinel subjects should be enrolled. The study will be conducted at Emory University Vaccine and Treatment Evaluation Unit (VTEU). This trial is expected to take approximately 48 months to complete. The duration of each subject's participation is approximately 13 months, from recruitment through the last study visit. The primary objectives of this study are: 1) Assessment of the safety, tolerability, and reactogenicity of one dose of ChAd155-RG at 5x1010vp per dose, or one or two doses of ChAd155-RG at 1x1011vp per dose; 2) Comparison of the safety, tolerability, and reactogenicity of one or two doses of ChAd155-RG, with three doses of RABAVERT. The secondary objective is to assess the serum rabies VNA levels by a standard, WHO-approved, RFFIT, as assessed by immune response kinetics (through approximately 12 months after first dose of vaccine), seroconversion rates, and peak GMT in each treatment arm.

Conditions

• Rabies
• Rabies Immunisation

Interventions

Type	Name	Description
BIOLOGICAL	ChAd155-RG	The ChAd155-RG Vaccine consists of a replication-defective group C ChAd, ChAd155, expressing RG under the control of the CMV promoter. The RG sequence cloned into the ChAd155 vector is a medoid, a natural viral strain with the highest average percent of amino acid identity among all RG sequences annotated in the NCBI database. The selected RG (NCBI strain AGN94271) shares an average 94% percent identity to the RGs in current vaccines.
OTHER	Placebo	0.9% Sodium Chloride, USP injection.
BIOLOGICAL	Rabies Vaccine	The RABAVERT Vaccine is an inactivated, purified chick embryo cell vaccine (PCECV). It consists of lyophilized rabies virus (strain Flury LEP) that has been propagated in chicken fibroblasts, inactivated with beta-propiolactone, and concentrated and purified by centrifugation

Timeline

• Start date: 2019-09-19
• Primary completion: 2023-03-24
• Completion: 2023-03-24
• First posted: 2019-07-15
• Last updated: 2024-06-03
• Results posted: 2024-04-10

Locations

1 site across 1 country: United States

Regulatory

• FDA-regulated drug study