GlaxoSmithKline (GSK) has reported that its Phase III trial designed to evaluate the efficacy of HZ/su, an investigational vaccine for the prevention of shingles, met its primary endpoint.
Primary endpoint of the trial is the overall vaccine efficacy (VE) of the candidate vaccine HZ/su across all age groups compared to placebo in reducing the risk of developing shingles.
The trial showed that HZ/su reduced the risk of shingles by 97.2% in adults aged 50 years and older compared to placebo.
HZ/su is a new vaccine candidate that combines gE, a protein found on the virus that causes shingles, with an adjuvant system, AS01B, which is intended to improve the immunological response.
The company said that these are the first results from the ZOster Efficacy trial in adults aged 50 years and over (ZOE-50).
The randomised, observer-blind, placebo-controlled, multicentre, multinational Phase III ZOE-50 trial included 16,160 adults aged 50 years and older.
During the trial, doses were given intramuscularly on a two-dose schedule at zero and two months.
Started in August 2010, the Phase III trial is ongoing in 18 countries and involves more than 16,000 individuals.
GSK Vaccine Development leader Alain Brecx said: "It's great news that the ZOE-50 trial has met its primary endpoint and I would like to thank all those involved in the clinical development programme.
"If approved, this candidate vaccine may offer an important option for the prevention of shingles, a painful disease that negatively impacts peoples' health and quality of life.
"We look forward to sharing these compelling results and additional data from the ZOE-50 study and the broader HZ/suclinical development programme with the scientific and regulatory communities."
The completed set of safety data from the ZOE-50 trial is currently being analysed and will be disclosed in the coming months.
In these trials the most common adverse events seen with HZ/su included local reactions including pain, redness, swelling at the injection site and systemic symptoms such as muscle pain, fatigue and headache.
Image: GlaxoSmithKline headquarters in Brentford, London, England. Photo: courtesy of Maxwell Hamilton.