Two oral COVID-19 treatments get provisional approval from TGA

Australia’s Therapeutic Goods Administration (TGA) has today granted provisional approval to two oral COVID-19 treatments for use in adults at increased risk of progression to hospitalisation or death.

Both PAXLOVID (manufactured by Pfizer Australia) and LAGEVRIO (manufactured by the Australian subsidiary of Merck) are to be administered as soon as possible after diagnosis of COVID-19 and within five days of the start of symptoms.

The TGA notes the pills, intended for those who do not require the initiation of oxygen, are not a substitute for vaccination against COVID-19.

LAGEVRIO is available as capsules, while PAXLOVID comprise separate tablets of nirmatrelvir and ritonavir - a drug usually used to treat HIV/AIDS. In both cases, the medicines are taken twice a day for 5 days.

“Molnupiravir (LAGEVRIO) works by inhibiting replication of the SARS-CoV-2 virus. The use of LAGEVRIO is not recommended in pregnancy and breastfeeding. It is recommended that sexually active women of childbearing potential use contraception and men also use contraception during and three months after treatment with LAGEVRIO,” the TGA says.

“Regarding PAXLOVID, the nirmatrelvir component blocks the activity of a protease enzyme that the coronavirus needs in order to replicate. Nirmatrelvir is administered in combination with low-dose ritonavir to maintain plasma levels of nirmatrelvir for the duration of the treatment.”

Both treatments have received conditional marketing authorisation from the UK Medicines and Healthcare Products Regulatory Agency and emergency use authorisation from the US Food and Drug Administration, and PAXLOVID was authorised by Health Canada earlier this week.

According to a Phase 2/3 study of Pfizer's pill, the treatment was found to reduce the risk of hospitalisation or death by 89 [er cent compared to placebo in non-hospitalised high-risk adults with COVID-19.

"These data suggest that our oral antiviral candidate, if approved or authorised by regulatory authorities, has the potential to save patients’ lives, reduce the severity of COVID-19 infections, and eliminate up to nine out of ten hospitalisations," Pfizer chairman and CEO Albert Bourla said.

"Given the continued global impact of COVID-19, we have remained laser-focused on the science and fulfilling our responsibility to help healthcare systems and institutions around the world while ensuring equitable and broad access to people everywhere.”

The TGA’s provisional approval means both treatments are subject to certain strict conditions, such as the requirement for the sponsors to continue providing information to the TGA on longer-term efficacy and safety from ongoing clinical trials and post-market assessment.

“Australians can be confident that the TGA's review process of both medicines was rigorous,” the TGA says.

“The decision to provisionally approve the medicine was informed by expert advice from the Advisory Committee on Medicines (ACM), an independent committee with expertise in scientific, medical and clinical fields including consumer representation.”

So far, the Australian Government has secured access to 500,000 treatment courses of PAXLOVID and 300,000 courses of LAGEVRIO for supply during 2022, with the first deliveries of both medicines anticipated in coming weeks.

Updated at 9.56am AEDT on 20 January 2022.