1930. Estimating the Potential Public Health Impact of Introducing the HZ/su Vaccine in the US Population Aged ≥50 Years
Session: Poster Abstract Session: Vaccines: Varicella/Zoster
Saturday, October 10, 2015
Room: Poster Hall
Background:

A new candidate subunit vaccine (HZ/su) containing the varicella-zoster virus glycoprotein E and the AS01Adjuvant System was shown to reduce herpes zoster (HZ) incidence in subjects ≥50 years old by 97.2% (95% CI: 93.7% - 99.0%; p<0.0001) in the Phase III ZOE-50 study. The public health impact of vaccinating the ≥50 year old population in the US with HZ/su vaccine was assessed.

Methods:

The population data for the US were obtained from US Census Bureau estimates. The mortality rates were calculated from the abridged US life tables. Incidence data for HZ were taken from Ortega-Sanchez (2013) which used an average of the incidence rates presented in various sources from 1982-2011. The proportion of HZ subjects who subsequently develop post-herpetic neuralgia (PHN) and other non-pain complications were obtained from Yawn (2007). Vaccine efficacy data for HZ/su were taken from Lal (2015) which presents the data of the ZOE-50 study. It is assumed that the entire cohort receives both doses of the HZ/su vaccine two months apart and that there is no additional efficacy against PHN in breakthrough HZ cases. Two different waning rates (2% and 4%) were used to model the waning of the 2-dose vaccine efficacy. The analysis was performed using a multi-cohort static Markov model developed in MS Excel™ that uses an annual cycle length and models the progression of HZ. The model tracks a cohort for their entire lifetime and compares the outcomes against no vaccination.

Results:

The results for the two waning scenarios are presented below:

Waning Scenario

2%

4%

HZ Cases Avoided

14 899 662

11 460 949

PHN Cases Avoided

2 141 859

1 586 206

Complications Avoided

1 737 241

1 309 758

Number Needed to Vaccinate to

 

 

… prevent 1 HZ case

7.15

9.30

… prevent 1 PHN case

49.76

67.19

Vaccinating 106,579,731 subjects aged 50 and above in the US with two doses of the HZ/su vaccine could potentially prevent between 11.4M - 14.9M cases of HZ, 1.6M - 2.1M cases of PHN and 1.3M - 1.7M cases of other non-pain complications.

Conclusion:

Introduction of the HZ/su candidate vaccine could potentially reduce the burden of HZ and its complications in the US population aged 50 and older.

Lijoy Varghese, MBA1, Desmond Curran, PhD1, Songkai Yan, M.S.2, Girishanthy Krishnarajah, Ph.D.3 and Antonio Olivieri, MD1, (1)GSK Vaccines, Wavre, Belgium, (2)US Health Outcomes & Epidemiology, GlaxoSmithKline: USHO & Epi - Vaccines, Philadelphia, PA, (3)US Health Outcomes & Epidemiology - Vaccines USMA Health Outcomes, GlaxoSmithKline: USHO Vaccines, Philadelphia, PA

Disclosures:

L. Varghese, GSK group of companies: Employee , Salary

D. Curran, GSK group of companies: Employee , Salary
GSK group of companies: Employee , stock options

S. Yan, GSK group of companies: Employee , Salary
GSK group of companies: Employee , Restricted shares

G. Krishnarajah, GSK group of companies: Employee , Salary
GSK group of companies: Employee , Stocks

A. Olivieri, GSK group of companies: Employee , Salary

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