Health authorities have expanded access to oral antiviral treatments for Covid-19 to millions of Australians.
As of Monday, all Australians over 70 with Covid are eligible for two antivirals – Lagevrio and Paxlovid – on the Pharmaceutical Benefits Scheme, as are a greater number of people at risk of severe disease.
Here’s how the antivirals work, how to access the drugs and what to keep in mind if you’re on other medication.
What are the Covid antivirals?
The oral antivirals Lagevrio and Paxlovid prevent the Sars-CoV-2 virus from replicating in the body.
“They’ve both been shown to reduce the chance of progressing to hospitalisation and severe disease,” said Associate Prof Paul Griffin, the director of infectious diseases at Mater Health Services.
Paxlovid is a combination of two drugs, nirmatrelvir and ritonavir, while Lagevrio is the brand name for the antiviral molnupiravir.
The nirmatrelvir in Paxlovid inhibits an enzyme – a viral protease – that the virus requires to reproduce.
“Lagevrio has a cooler-sounding mechanism of action in that it causes ‘viral error catastrophe’ by very significantly altering how that virus reproduces,” Griffin said.
Who is eligible for the drugs?
Eligibility on the PBS has been expanded to include people over 70, those older than 50 with two or more risk factors for severe disease, and Aboriginal and Torres Strait Islander people aged over 30 with two or more risk factors.
People 18 and older who are moderately to severely immunocompromised are also eligible.
How do you access the Covid antivirals?
Access to Lagevrio and Paxlovid requires a prescription from an authorised doctor or nurse practitioner.
“People can get antivirals after speaking to a doctor, but they need to act fast,” said the health minister, Mark Butler. “Speak to your GP and make a plan for what you will do if you get Covid, so you can start taking antivirals as soon as possible after your positive result.”
Lagevrio was listed on the PBS on 1 March and Paxlovid on 1 May. “These remarkable treatments that normally cost more than $1,000 will only be $6.80 for a concession card holder and around $40 for everyone else,” Butler said.
The treatments are only suitable for adults with mild-to-moderate Covid-19 and must be taken within five days of symptoms starting.
“Timing is really one of the big things here,” Griffin said. “You need to get it within five days, but the first three days is better.
“If you’re in a high-risk category – have a think about how you might get [the antivirals] before you get Covid.
“A lot of GPs are very good at doing telehealth, but GPs are obviously inundated at the moment.”
Griffin added that people could also consider scoping out the location of their nearest pharmacy that does deliveries.
Are there any contraindications?
Lagevrio and Paxlovid may affect foetal development and are not recommended for people who are pregnant or breastfeeding.
The second component of Paxlovid, ritonavir, interacts with many other drugs, including certain antidepressants, anxiolytics and statins. Paxlovid can also affect the effectiveness of hormonal contraceptives.
“People with impaired liver and kidney function need to be very careful [with Paxlovid],” Griffin said.
He emphasised that the antivirals were not a replacement for vaccination.
