UK drug manufacturer GlaxoSmithKline (GSK) has reported positive results from its phase three ZOE-70 study of Shingrix to treat shingles.
Shingrix has been developed as a non-live, adjuvanted, subunit (HZ/su) vaccine to prevent herpes zoster and its related complications.
Shingles is caused by the reactivation of latent chickenpox virus, triggering a painful, itchy rash on one side of the body.
The candidate vaccine features a combination of glycoprotein E, which is found on the varicella zoster virus (VZV) causing shingles, with the AS01B adjuvant system designed to improve the immunological response to the antigen.
The phase three ZOE-70 trial is a randomised, observer-blind, placebo-controlled (saline solution) multicentre, multinational study, which involved more than 14,800 adults aged 70 years and older.
The subjects were administered intramuscularly with two doses of Shingrix with an interval of two months.
The study was primarily focused to determine the overall vaccine efficacy against shingles in people aged 70 and over, compared to the placebo. The results demonstrated a sustained efficacy across the various age groups included in the study.
The candidate vaccine also proved effective in reducing the risk of subsequent chronic neuropathic pain, also known as postherpetic neuralgia (PHN), which is a commonly occurring complication related to shingles.
GSK vaccines research and development senior vice-president Dr Emmanuel Hanon said: “This is the first time that such high efficacy has been demonstrated in a vaccine candidate for older people and it is remarkable, as we know that these people frequently have an age-related weakening of their immune system.
“If approved, this candidate vaccine could be an important tool for the prevention of shingles and the pain associated with it, which would significantly impact the health and quality of life of so many people.”
The phase three ZOE-70 trial ran parallel with the phase three ZOE-50 trial of Shingrix, which involved 16,160 adults aged 50 years and older.
An analysis of the results of both trials has demonstrated the efficacy of Shingrix against shingles.
Image: Child with shingles on arm and hand. Photo: courtesy of James Heilman via Wikipedia.