Persistence of Protection by Shingrix

The primary endpoint of this study was the area under the concentration/time curve of quantitative VZV DNA in plasma. However, all the VZV DNA measurements were below the lower limit of quantitation of the assay. Due to this unexpected outcome, we performed a qualitative analysis of presence or absence of VZV DNA in plasma at Day ≥3 after the vOka challenge.

Inclusion criteria

• Age 50-85
• General good health
• Women of non-childbearing potential must be postmenopausal or have undergone hysterectomy or bilateral oophorectomy
• ARM 1 ONLY: Documented evidence of immunization with ZVL or SRX at least 5 years previously
• ARM 2 ONLY; Documented evidence of immunization with ZVL 6-12 months prior to enrollment
• ARM 3 ONLY: Have never received any shingles vaccination

Exclusion criteria

• Prior history of herpes zoster (HZ)
• Blood products received in the 3 months prior to study enrollment or planned for the subsequent week for Arm 1; Arm 2 requires same exclusion; Arm 3 extends the exclusion to the week after the vOka challenge, which is 6 months after completing SRX administration.
• Significant immune suppressive illness or therapy
• Concomitant vaccine received within 2 (inactive) or 4 (live) weeks prior to the study or during the first week of the study.
• Women of childbearing potential.
• Pregnancy or breastfeeding.
• Participation in a concurrent clinical study in which the subject will be exposed to and investigational product during the period starting 7 days before the first dose of study vaccine through the completion of the study.