10 Dec 2022

Covid-19 antiviral medications: What you need to know

3:22 pm on 10 December 2022
hand with pills

Photo: RNZ

Cases of Covid-19 are surging in the lead-up to Christmas, with new daily cases this week peaking close to 7500.

A handful of antiviral medicines that may help prevent serious sickness are available in New Zealand. In September, Pharmac widened access to three treatments, saying the move would more than double the number of people who could get them for free.

Health advocates are concerned some people are still missing out, especially those in communities facing health inequities.

There are also concerns back-pocket prescriptions, when a script is given out just in case, might put some people at risk.

What Covid-19 antivirals are available in New Zealand?

The main treatments people with Covid-19 can have at home in New Zealand are Paxlovid (nirmatrelvir with ritonavir) or molnupiravir (marketed as Lagevrio). They're given as pills or capsules. Since 28 July, Paxlovid and molnupiravir have been available to some groups of at-risk people without a doctor's prescription.

Other drugs, including remdesivir, which is given by intravenous infusion, are available at hospitals.

How do they slow or stop the virus?

According to Pharmac's website, Paxlovid stops the coronavirus multiplying and spreading through the body. It comes as two separate pills: nirmatrelvir, which blocks the virus from making copies of itself, and ritonavir, which slows the breakdown of nirmatrelvir.

The website says molnupiravir also works by inhibiting virus replication.

Both treatments must be started during the first five days of symptoms.

Who can get them?

People considered to be at higher risk of severe illness and hospitalisation are the top priority. As of 14 September, the following groups may be eligible for publicly-funded Paxlovid and molnupiravir, as long as they have Covid-19 and their symptoms started within the last five days:

  • Māori or Pacific people aged 50 years or older
  • Anyone aged 65 years or older
  • Anyone aged 50 years or older who has had fewer than two Covid-19 vaccinations
  • Other people with at least one of the following: a severely weakened immune system; Down syndrome; sickle cell disease; a previous admission to critical care or high dependency care because of Covid-19; three or more high risk medical conditions.

It's important to note that even if a person meets these criteria, the drugs aren't always going to be the right choice for them - a trusted health professional can help here.

How many people are currently taking them?

According to the most recent figures from Te Whatu Ora - Health New Zealand, a total of more than 76,300 courses of Covid-19 oral antiviral medicines have been supplied from 686 pharmacies - more than 23,700 of these in the last 30 days.

Currently about 5000 courses are being dispensed each week, which represents about 14 percent of cases.

Chart from Te Whatu Ora showing courses of Covid-19 oral  antiviral medicines dispensed by month - Sept - Nov 2022.

Photo: Te Whatu Ora/Supplied

Source: Te Whatu Ora (9 December 2022). "Prescriptions" refers to antivirals prescribed by a GP, while "Pharmacists" refers to antivirals that were provided directly by the pharmacist.

How do people get them?

Health Navigator, which is supported by Pharmac, Te Whatu Ora, and the Royal New Zealand College of General Practitioners, summarises the different ways people can get access to the treatments. It says there are two ways to get antivirals: a prescription from a doctor or nurse practitioner, or by calling a pharmacist, who might be able to send them out without a prescription after they've done a health check over the phone.

Not all pharmacies offer this service. Healthpoint has a search tool to find those that do.

The Royal New Zealand College of General Practitioners expressed concern in July, when the rules were being relaxed, that it could compromise patient safety.

The college's medical director Dr Bryan Betty, who is a GP in Cannons Creek, Porirua, told RNZ the system appeared to be working.

"One of the medications, Paxlovid, has quite significant drug-to-drug interactions, or needs dose adjustment. Our concerns were that, one, if the pharmacist was prescribing - if there were concerns over other medication, that there was communication with the [patient's] GP. And two, because of these dose adjustments, or stopping medication, we weren't keen on what are called back-pocket scripts - you get a script and you just keep it for the time you get Covid - because that could lead to problems."

He said, anecdotally, very few back-pocket scripts were being given out, and the process with pharmacists had also "probably worked out reasonably well".

Betty said, generally speaking, medical centres across the country are making good use of the medications. It would be more challenging for people who already had trouble getting medical care, such as remote rural communities or those with very high needs, including within Māori or Pacific communities, "but there's been a lot of effort put in by the system to try to ensure access".

Matakāoa Covid-19 response lead Tina Ngata told Stuff's Hannah Martin this week that some parts of Tairāwhiti still had very inconsistent access.

How good is the evidence they work?

Available evidence will change all the time. Betty said it was important to understand the medications were for those at risk of hospitalisation.

"Essentially the medication isn't good for everyone in New Zealand. It's very targeted because that's where the evidence sits. Not everyone who gets Covid should have access to the medication. Again, it's those who tend to end up in hospital, or with more serious disease."

What are the risks?

To again draw on Health Navigator, the best type of medicine for a particular person will depend on their medical conditions, any other medicines they're taking, including rongoā rākau and herbal medicines, and the antiviral drugs' possible side effects. The September 2022 Medsafe fact sheet for Paxlovid for example, says people with reduced kidney or liver function should talk to their doctor before taking it, and makes it clear taking it alongside certain other medications can be life-threatening. It also says it shouldn't be taken by people who are pregnant.

Where can people get more information?

People who are sick or who have any other medical concerns should contact a medical professional. The information in this article is sourced from Health Navigator, the Ministry of Health, Pharmac, Medsafe and Te Whatu Ora.

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