Shingrix vaccine and very rare risk of Guillain-Barré Syndrome
Summary
We have received Australian reports of Guillain-Barré Syndrome (GBS) following Shingrix vaccination.
After investigating this issue and seeking advice from an expert panel, the Product Information (PI) and Consumer Medicine Information (CMI) documents for Shingrix were updated. These changes reflect the new reporting data, recognising that GBS is a very rare adverse event.
A warning about GBS was already included in the Shingrix PI. This described the findings of an observational study in individuals aged 65 years or older which showed an increased risk of GBS (estimated 3 excess cases per million doses administered) observed during the 6 weeks following vaccination.
What health professionals should do
Health professionals should be aware of GBS cases following vaccination with Shingrix. Patients should be warned of this possible but very rare risk and encouraged to seek medical attention if they experience symptoms, as early medical care can reduce severity and improve outcomes.
Shingrix is not generally recommended for people with a history of GBS whose first episode occurred within 6 weeks of receiving any vaccine (such as an influenza vaccine or a previous dose of Shingrix vaccine). Those with a history of GBS not associated with Shingrix should discuss the risks and benefits of receiving Shingrix with a health professional.
Symptoms of GBS include pins and needles (paraesthesia), numbness, weakness and paralysis. Typically, hands and/or feet are affected first, with symptoms progressing up the body to the legs, arms, face and muscles involved with breathing. These symptoms may progress over a few days or weeks.
We continue to monitor adverse events associated with Shingrix and encourage health professionals to report suspected cases of GBS and other neuroinflammatory conditions after vaccination.
Background
Shingrix is a non-live vaccine based on the varicella-zoster virus glycoprotein E (gE). It is indicated for the prevention of herpes zoster and post-herpetic neuralgia in:
- adults 50 years of age or older
- adults 18 years of age or older at increased risk of shingles.
Shingrix replaced Zostavax (a live shingles vaccine) on the National Immunisation Program in November 2023. A 2-dose course of Shingrix is free for eligible people at moderate to high risk of severe illness and complications from shingles. This includes:
- people aged 65 years and over
- Aboriginal and Torres Strait Islander people aged 50 years and over
- people aged 18 years and over who have an increased risk of herpes zoster due to an underlying condition or because they are receiving immunosuppressive treatment.
Guillain-Barré Syndrome (GBS)
GBS is a rare immune disorder in which the body’s immune system attacks nerve cells. The causes are not fully understood, but it can occur after an infection (such as influenza) and has been reported after some types of immunisations, including for COVID-19.
GBS causes nerve inflammation and can result in pain, numbness, muscle weakness and difficulty walking or breathing. It tends to affect both sides of the body. Most people recover fully, although this may take years and some continue to experience weakness.
Our investigation
We began an investigation into the possible association between Shingrix and GBS in February 2024 after receiving two reports detailing this adverse event.
The Shingrix PI already contained information about an observational study in people aged 65 years and over. The study found an increased risk of GBS (estimated 3 excess cases per million doses administered) observed in the 42 days following vaccination. The PI noted that the evidence was insufficient to determine a causal relationship.
At the time, GBS following Shingrix vaccination had also been reported to the World Health Organisation’s global adverse event reports database. We also identified published literature that suggested a possible association between Shingrix and GBS.
Our investigation recommended that GBS be included in the adverse event section of the Australian Shingrix PI. This update harmonises the Australian PI with corresponding information from the United States and Canada.
The association between GBS and Shingrix was also considered by an independent expert advisory group on immunisation. This review included discussion of a single adverse event report involving Shingrix and meningoencephalitis. The expert group agreed that inclusion of GBS as an adverse event in the Shingrix PI was appropriate and recommended raising awareness of the possibility of GBS following Shingrix.
We continue to monitor adverse events associated with Shingrix and other vaccines, including rare adverse events such as GBS.
Current mentions of GBS in the PI
4.4 SPECIAL WARNINGS AND PRECAUTIONS FOR USE
In a post-marketing observational study in individuals aged 65 years or older, an increased risk of Guillain-Barré syndrome (estimated 3 excess cases per million doses administered) was observed during the 42 days following vaccination with Shingrix. Available information is insufficient to determine a causal relationship with Shingrix.
4.8 ADVERSE EFFECTS (UNDESIRABLE EFFECTS)
Up-to-date information for Shingrix can be found in the Product Information (for health professionals) and the Consumer Medicine Information (for consumers).
GBS cases reported to the TGA
Our public Database of Adverse Event Notifications included 13 reports of GBS following Shingrix vaccination up to 18 September 2024. The reports involved patients of both sexes. All were aged from their mid-60s to mid-80s. No deaths were reported.
Further reading
Goud R, et al. Risk of Guillain-Barré Syndrome following recombinant zoster vaccine in Medicare beneficiaries. JAMA Intern Med 2021;181:1-8. doi: 10.1001/jamainternmed.2021.6227
Janusz CB, et al. Projected risks and health benefits of vaccination against herpes zoster and related complications in US adults. Hum Vaccin Immunother 2022;18:2060668. doi: 10.1080/21645515.2022.2060668
Nelson JC, et al. Active postlicensure safety surveillance for recombinant zoster vaccine using electronic health record data. Am J Epidemiol 2023;192:205-216. doi: 10.1093/aje/kwac170
U.S. Food & Drug Administration. FDA Requires a warning about Guillain-Barré Syndrome (GBS) be included in the prescribing information for Shingrix. FDA Safety Communication, March 2021.
Disclaimer
Medicines Safety Update is aimed at health professionals. It is intended to provide practical information to health professionals on medicine safety, including emerging safety issues. The information in Medicines Safety Update is necessarily general and is not intended to be a substitute for a health professional's judgment in each case, taking into account the individual circumstances of their patients. Reasonable care has been taken to ensure that the information is accurate and complete at the time of publication. The Australian Government gives no warranty that the information in this document is accurate or complete, and shall not be liable for any loss whatsoever due to negligence or otherwise arising from the use of or reliance on this document.
© Commonwealth of Australia 2024
This work is copyright. You may reproduce the whole or part of this work in unaltered form for your own personal use or, if you are part of an organisation, for internal use within your organisation, but only if you or your organisation do not use the reproduction for any commercial purpose and retain this copyright notice and all disclaimer notices as part of that reproduction. Apart from rights to use as permitted by the Copyright Act 1968 or allowed by this copyright notice, all other rights are reserved and you are not allowed to reproduce the whole or any part of this work in any way (electronic or otherwise) without first being given specific written permission from the Commonwealth to do so. Requests and inquiries concerning reproduction and rights are to be sent to the TGA Copyright Officer, Therapeutic Goods Administration, PO Box 100, Woden ACT 2606 or emailed to tga.copyright@tga.gov.au.
For the latest safety information from us, subscribe to the TGA Safety Information email list via our website.
Medicines Safety Update is written by staff from our Pharmacovigilance Branch.
Editor: Dr Megan Hickie
Deputy Editor: Aaron Hall
Related content
-
Updated warnings for Respiratory Syncytial Virus vaccines Arexvy and Abrysvo
Risk of Guillain-Barre syndrome added to Product Information. -
Azithromycin and rare risk of cardiovascular death
An updated warning about the risk of sudden cardiovascular death has been added to the Product Information and Consumer Medicine Information documents for azithromycin. -
More prominent safety warnings about the neuropsychiatric effects of montelukast
Additional safety information is being added to all montelukast products to strengthen and highlight existing warnings about serious neuropsychiatric events.