Elderly Australians may not get early access to a coronavirus vaccine if the medicine has not been trialled on older age groups.
Department of Health secretary Brendan Murphy said older Australians were considered the most vulnerable and they would be the priority for receiving a vaccine.
“However, most of the vaccines have not been trialled in the over-65s and it’s quite likely that the first registrations of some vaccines will exclude them being used in over-65s,” Murphy told a Senate estimates hearing on Tuesday.
“So we then have to think about a second level priority.”
In a JAMA Internal Medicine article, a group of US researchers led by Benjamin Helfand from the University of Massachusetts and Brown University, said there is a long history of exclusion of older adults from clinical trials.
“If the older age group is excluded from vaccine trials, efforts to ensure effectiveness, titrate dosage or frequency, and assess adverse effects in the group most vulnerable to COVID-19 will not be possible.
“Antibody responses to vaccines may decrease with age, and can improve with increasing antigen levels, adjuvants, or repeated dosing.”
The academics said while some have argued that only vaccination of younger populations is needed to achieve herd immunity, the high level of immunity required, coupled with the fact that settings like nursing homes are comprised nearly exclusively of older adults, highlights “the imperative for their inclusion in COVID-19 vaccine trials”.
The team said while some exclusions for severe or uncontrolled comorbidities will be essential to protect the health and safety of older adults, “caution must be taken to avoid excluding otherwise eligible participants for reasons that are not well-justified”.
This week, The Financial Times reported that the COVID-19 vaccine being developed by the University of Oxford produces an immune response in both young people and older adults.
Immunogenicity blood tests carried out on a subset of older participants echo data released in July that showed the vaccine generated “robust immune responses” in a group of healthy adults aged between 18 and 55, the newspaper reported on Monday.
However, it added positive immunogenicity tests do not guarantee the vaccine will ultimately prove safe and effective in older people. That will not be known until full trial data for the age group has been analysed.
Murphy said an expert committee was developing a range of vaccine strategies taking into account the potential limitations of various drugs.
“This is a logistic challenge of the likes we’ve never seen before, so we are going to need a range of strategies,” Murphy told senators.
“We haven’t landed all of those plans yet because they’re all very complex.”
Special teams would be set up to vaccinate aged care staff and residents, if it’s deemed safe for older Australians.
If not, aged care staff only may be immunised until a vaccine that’s safe for the elderly is available.Do you have an idea for a story?
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