Phase 1 Trial of CMV Towne Vaccine in Subjects Previously Received VCL CT02 Vaccine ID or IM
Objectives of this trial are to:
- Evaluate the kinetics and magnitude of the CMV-specific immune response post-Towne challenge (3000 pfu) in healthy CMV-seronegative volunteers who received VCL CT02 administered ID or IM 9 to 15 months previously as measured by: 1) ELISA and/or virus-neutralizing antibody titers for gB; 2) T-cell IFN-g ELISPOT; 3) T-cell proliferation assays (CFSE) for IE1, pp65, and/or gB; and possibly 4) cytokine and phenotypic flow cytometry responses to pp65, IE1, and/or gB.
- Evaluate the safety safety of Towne challenge in healthy CMV-seronegative adult subjects who have previously been immunized with a trivalent pDNA CMV vaccine (VCL-CT02) administered intramuscularly (IM) or intradermally (ID).
Our hypothesis is that the immune response to Towne vaccine 3000 pfu challenge after VLC-CT02 priming will be greater than that after Towne vaccination alone (concurrent controls will be administered Towne alone in a concurrent, companion trial).
|Study Design:||Allocation: Non-Randomized
Endpoint Classification: Safety/Efficacy Study
Intervention Model: Single Group Assignment
Masking: Open Label
Primary Purpose: Prevention
|Official Title:||A Phase 1 Clinical Trial to Evaluate the Safety of, and Kinetics and Magnitude of the CMV-Specific Immune Response to, Challenge With a Live Attenuated Strain of CMV (Towne) in Healthy, CMV- Seronegative, Adult Subjects Who Previously Received a CMV Immunotherapeutic Trivalent pDNA Vaccine (VCL CT02) Administered Intradermally or Intramuscularly|
- CMV-specific immune response post-Towne challenge: gB antibody, T-cell IFN-g ELISPOT, T-cell proliferation assays for IE1, pp65, and/or gB, cytokine and phenotypic flow cytometry responses to pp65, IE1, gB.
- Safety of Towne challenge in subjects who have previously been immunized with a trivalent pDNA CMV vaccine (VCL-CT02).
|Study Start Date:||September 2006|
|Estimated Study Completion Date:||August 2007|
This is a Phase 1, single-center, open-label trial of the live, attenuated Towne CMV vaccine administered as a “challenge” to healthy, CMV-seronegative, adult subjects who previously received the CMV immunotherapeutic trivalent pDNA-based vaccine, VCL-CT02, given by intradermal or intramuscular routes as described in the following table; these subjects have been followed for 32 weeks.
Table 6.1 Subject Distribution Group Formulation Dosing Regimen (day) Dose per Injection(Administered to the deltoid region) Route of Administration Number of Subjects
- VCL-CT02 0, 28, 56 1.0 mg Intramuscular (IM) 6
- VCL-CT02 0, 28, 56 100 μg/injection × 2 injections Intradermal (ID) 11 Total 17
Up to 10 subjects from Groups 1 and 2 will be approached for enrollment in the current protocol. If a subject consents and meets all eligibility criteria, the subject will receive Towne (3000 pfu subcutaneously) between 9 and 15 months after the subject’s first dose of VCL-CT02. Safety will be monitored and Both antibody to CMV gB and T-cell responses to CMV antigens will be measured at specified intervals for 252 days post Towne challenge.