Scientists have made a significant breakthrough in the battle against the deadly respiratory syncytial virus (RSV). After a 60-year quest in search of an effective vaccine for the disease, which each year kills about 100,000 and hospitalises about 3.6 million people around the world, researchers are confident they have found the ‘holy grail’.
A vaccine named Arexvy has been developed by GSK Australia (formerly known as GlaxoSmithKline). It is being assessed for use by Australians aged 60 and over by regulatory body the Therapeutic Goods Administration (TGA). If approved, it could be available to older Australians next year.
Results of a clinical trial conducted on 24,966 participants showed vaccine efficacy was 94.1 per cent against severe RSV-related lower respiratory tract disease (assessed on the basis of clinical signs or by the investigator) and 71.7 per cent against RSV-related acute respiratory infection.
The results, published in the New England Journal of Medicine, also showed that the vaccine was similarly effective against a number of RSV subtypes.
The report concludes: “A single dose of the RSVPreF3 OA vaccine [Arexvy] had an acceptable safety profile and prevented RSV-related acute respiratory infection and lower respiratory tract disease and severe RSV-related lower respiratory tract disease in adults 60 years of age or older, regardless of RSV subtype and the presence of underlying coexisting conditions.”
However, while Arexvy has been given preliminary approval for use in the US by the Food and Drug Administration (FDA), concerns have been raised about potential side-effects of an equivalent RSV vaccine developed by Pfizer.
Several FDA panel members expressed those concerns, citing two cases in the trial, one of which involved a Pfizer patient developing Guillain-Barré syndrome (GBS) and another a subtype of GBS known as Miller Fisher Syndrome.
While the first of those cases was assessed as life-threatening, it had what is known as a ‘confounding factor’ – the patient had suffered a heart attack the day before developing the condition.
One recipient of the GSK version of the vaccine also developed GBS, and required several months of hospital rehabilitation.
Adverse effects are, of course, not uncommon with drugs, and regulatory bodies will weigh up the risks of the vaccine compared to the risks of not taking the RSV vaccine.
In these cases. the FDA voted 10-2 in favour of GSK’s Arexvy preliminary approval, and 7-4 (with one abstention) in favour of the Pfizer vaccine. Pfizer has not yet sought approval from the TGA, but is expected to do so.
News of the Arexvy application coincides with a new report published by GSK calling for a redesigned National Immunisation Program (NIP), with “increased Australian government investment in innovative vaccines and better access through a redesigned NIP focused on older adults”.
“Our health system and economy face once-in-a-generation challenges, and policy makers are considering the reforms and investments needed to secure Australia’s future,” says Dr Alan Paul, country medical director at GSK Australia.
“With our ageing population and the challenges of increasing productivity, preventing disease has never been more important.”
That’s a sentiment few older Australians would argue against.
Have you ever had RSV? Would you be willing to have the new vaccine if it receives TGA approval for use in Australia? Why not share your thoughts in the comments section below?
