Editor’s note: The PBS criteria for Paxlovid and Lagevrio have changed since this article was published and a COVID therapies helpline is now available for PBS prescribers.
We have attempted to unravel the complexity of prescribing and accessing oral COVID-19 treatments for adults with mild to moderate COVID-19 infection.
We are now into the third year of the COVID-19 pandemic. A recurring theme has been the rapidly changing clinical landscape – we’ve seen testing, isolation and vaccine recommendations changing seemingly overnight since 2020.
GPs are currently referring most patients to hospital-based COVID-19 clinics to receive COVID-19 oral medications. However, with Paxlovid® and Lagevrio® now listed on the Pharmaceutical Benefits Scheme (PBS), we will see that landscape change again. As hospital clinics reduce their capacity or close in coming months, GPs will play a more central role in treating COVID-19 infections.
Which COVID-19 antiviral treatments are on the PBS for GPs to prescribe?
Nirmatrelvir and ritonavir (packaged together as Paxlovid) became available on the PBS on 1 May 2022. Molnupiravir (Lagevrio) has been PBS-listed since March 1 2022.
What are the indications for prescribing these medicines?
Both treatments are PBS-funded for adults who have mild to moderate COVID-19 (that is, not requiring oxygen), confirmed by a PCR or medically verified RAT, and who are:
- patients aged 65 or older, with 2 other risk factors for severe disease
- patients aged 75 or older with one other risk factor
- patients of Aboriginal or Torres Strait Islander origin who are aged 50 or older with 2 further risk factors for severe disease
- any patient over the age of 18 who is moderately to severely immunocompromised.
Treatment must be started within 5 days of symptom onset.
The PBS listings for Paxlovid and Lagevrio include the definition of risk factors and immunocompromising conditions.
How can patients access these oral treatments?
There are 3 pathways that might trigger a prescription for a patient with mild or moderate COVID-19 infection.
Scenario 1
Patient is confirmed COVID positive and allocated to treatments at hospital-based clinics, triggered by the current Victorian Department of Health and local public health unit COVID-positive treatment pathways, without GP involvement.
Scenario 2
Patient is confirmed COVID positive and notifies a GP. The GP contacts a hospital-based clinic to discuss treatments. If the patient does not meet the criteria but there is a high level of clinical concern, this can also be discussed with clinics. For clinic locations and information on referral processes see COVID-19 Treatment Referrals on HealthPathways Melbourne.
Scenario 3
Patient is confirmed COVID positive and notifies a GP. The GP prescribes antivirals directly using a PBS script. The patient can then have someone collect the antivirals from a community pharmacy.
What are the prescription regimes?
Lagevrio: 4 capsules twice daily for 5 days.
Paxlovid: The standard dose is 2 x 150mg tablets of nirmatrelvir, together with one 100 mg tablet of ritonavir, twice daily for 5 days. However, the dose needs to be adjusted depending on renal function (see Table 1). Note that Paxlovid has multiple contraindications and drug interactions which are outlined in a handy newsGP article.
Dosage (source: newsGP)
| eGFR* | Paxlovid dose |
| Greater than 60 mL/min (normal renal function or mild renal impairment) |
300 mg nirmatrelvir with 100 mg ritonavir, taken twice daily for five days |
| ≥30 to ≥60 mL/min (moderate renal impairment) |
150 mg nirmatrelvir with 100 mg ritonavir, taken twice daily for five days |
| <30mL/min (severe renal impairment) |
Paxlovid is not recommended (the appropriate dose has not been determined) |
*eGFR = estimated glomerular filtration rate based on the Chronic Kidney Disease-Epidemiology Collaboration (CKD-EPI) formula.
What are the challenges to prescribing these medications in the general practice setting?
Timeliness of notification
These medications are only PBS-funded if they can be prescribed within 5 days of the onset of symptoms – a tight timeframe! Some patients might delay their test until several days after symptom onset, and GPs are not always notified of COVID-19 infections under the current treatment pathways. Also, not all high-risk patients are identified for treatment through the treatment pathways – a patient may neglect to complete an SMS survey.
GPs should consider proactively educating high-risk patients before they contract COVID-19. These should be encouraged to contact the clinic as soon as possible if they test positive – regardless of whether you are prescribing. You could opportunistically remind high-risk patients at regular appointments or when giving COVID-19 booster vaccinations, or proactively conduct an email or SMS campaign.
Accessing medications
It might be difficult to source the drugs, especially given the tight timeframe. Practices may not know which local pharmacies are stocking the treatments. Community pharmacies may not find it feasible to keep a supply in stock because the medications are costly and expire quickly.
GPs should work with their team to decide whether their practice will prescribe the medications. If so, you could task someone – perhaps the practice manager – to find out which local pharmacies will be stocking them. (Note: they are already stocked in residential aged care facilities.)
If your practice decides not to prescribe these medications, you will need to quickly refer patients to hospital-based clinics, or consider referring to a general practice respiratory clinic (see below).
Providing appropriate appointments to COVID-positive patients
Practices may not be able to offer timely appointments for patients who have COVID-19. These are complex medications with similarly complex PBS access criteria (and in the case of Paxlovid, multiple interactions and contraindications). This is a big ask in a standard 15-minute GP appointment.
GPs should consider having some rapid access telehealth appointments available for COVID-positive patients for assessment for treatment.
GPs could also consider referring COVID-positive patients to general practice respiratory clinics (GPRCs). GPRCs can see COVID-positive patients face-to-face or by telehealth quickly if another practice cannot. Most can also prescribe oral antiviral treatments. GPRCs will provide patients’ regular GPs with a summary of the care provided within 48 hours.
More information
- HealthPathways Melbourne: COVID-19 treatment referrals
- Victorian Department of Health: Medications for patients with COVD-19
- PBS listings for Paxlovid and Lagevrio
- newsGP article on prescribing
- newsGP article on Paxlovid
- National Covid Clinical Evidence Taskforce risk stratification tools
- COVID therapies helpline
