The trial showed that vaccine efficacy was maintained across age groups, from 50 years to 70 years and above.
HZ/su vaccine candidate is non-live and combines gE, a protein found on the virus that causes shingles, with an adjuvant system, AS01B, which is expected to improve the immunological response to gE.
The primary endpoint of the trial showed that a two-dose schedule of HZ/su reduced the risk of herpes zoster by 97.2% in adults aged 50 years and older compared to placebo.
Currently, more trials are being carried out to evaluate the ability of HZ/su to prevent shingles in people aged 70 years and older and in adults with compromised immune systems.
Data from these trials will provide additional information with respects to the safety of HZ/su and its ability to stimulate immune responses in specific populations.
The trials will also address the degree to which HZ/su can prevent complications of shingles, such as chronic neuropathic pain, also called as post-herpetic neuralgia (PHN).
GSK Global Vaccines chairman Dr Moncef Slaoui said: "We are extremely encouraged that the results may point out a health benefit in the prevention of shingles.
"This disease can be painful and potentially debilitating for some people and older people are particularly at risk. We look forward to continuing the development of our Zoster programme"
The Phase III trial involved around 16,160 adults aged 50 years and older from North America, Europe, Latin America and Asia-Pacific.
The Phase III HZ/su study program included over 37,000 subjects globally to evaluate the efficacy, safety and immunogenicity of the vaccine candidate.
Image: GlaxoSmithKline headquaters in London, UK. Photo: courtesy of Maxwell Hamilton.