Systematic review of clinical studies suggests newer shingles vaccine far more effective

By Michael Oliveira

A systematic review of clinical studies involving more than two million patients aged 50 years and older suggests a recently released shingles vaccine was far more successful in preventing the painful condition compared to the older vaccine – but also carried greater risk of side-effects.

The research, led by Dr. Andrea Tricco, a scientist with St. Michael’s Hospital’s Li Ka Shing Knowledge Institute and associate professor at the University of Toronto’s Dalla Lana School of Public Health, was published by The BMJ.

The adjuvant, recombinant subunit vaccine – sold under the brand name Shingrix – was found to be 85 per cent more effective in reducing cases of shingles, also known as herpes zoster, compared to Zostavax, which is a live-attenuated shingles vaccine available for use in Canada since 2006.

The use of Shingrix did lead to 30 per cent more injection-site adverse events, such as redness or swelling. No statistically significant differences were identified between the two vaccines for serious adverse events and deaths.

“There haven’t been any head-to-head studies comparing the two shingles vaccines, so the results from our systematic review can be employed by policy-makers, clinicians, and patients to make their decisions on the use of these vaccines,” said Dr. Andrea Tricco, a scientist with St. Michael’s Hospital’s Li Ka Shing Knowledge Institute and associate professor at the University of Toronto’s Dalla Lana School of Public Health.

“If you have to choose between two vaccines and you have evidence showing that one of the vaccines is a little more effective, or a little safer than the other, then you might be more willing to take the safer and more effective one.”

Shingles is a viral infection that occurs through reactivation of latent varicella zoster virus, which causes chickenpox.

About one in four people will develop shingles in their lifetime and about two-thirds get it after the age of 50.

This review, which included 27 unique studies, was funded through an unrestricted research grant from the Canadian Institutes for Health Research Drug Safety and Effectiveness Network.

These papers are an example of how St. Michael’s Hospital is making Ontario Healthier, Wealthier, Smarter.

About St. Michael’s Hospital

St. Michael’s Hospital provides compassionate care to all who enter its doors. The hospital also provides outstanding medical education to future health care professionals in more than 29 academic disciplines. Critical care and trauma, heart disease, neurosurgery, diabetes, cancer care, care of the homeless and global health are among the Hospital’s recognized areas of expertise. Through the Keenan Research Centre and the Li Ka Shing International Healthcare Education Centre, which make up the Li Ka Shing Knowledge Institute, research and education at St. Michael’s Hospital are recognized and make an impact around the world. Founded in 1892, the hospital is fully affiliated with the University of Toronto.

St. Michael’s Hospital with Providence Healthcare and St. Joseph’s Health Centre now operate under one corporate entity as of August 1, 2017. United, the three organizations serve patients, residents and clients across the full spectrum of care, spanning primary care, secondary community care, tertiary and quaternary care services to post-acute through rehabilitation, palliative care and long-term care, while investing in world-class research and education.