Drugs List

Therapeutic Indications

Uses

Coronavirus disease 2019 (COVID-19) - treatment

Treatment of COVID-19 in adults who do not require supplemental oxygen and who are at increased risk for progression to severe COVID-19.

Contraindications

Children under 18 years
Breastfeeding
Chronic renal failure
Galactosaemia
Pregnancy
Severe hepatic impairment
Severe renal impairment

Precautions and Warnings

Females of childbearing potential
Active liver disease
Glucose-galactose malabsorption syndrome
Hepatic enzymes abnormalities
Hepatitis
Lactose intolerance
Moderate renal impairment

Reduce dose in patients with moderate renal impairment
Contains polysorbate
Some formulations contain lactose
Monitor patients receiving concurrent anticoagulants
Advise patient to seek advice at first indications of pregnancy
Advise patient not to take St John's wort concurrently
Female: Ensure adequate contraception during treatment
Female: Use barrier contraception during and for 1 month after treatment
Breastfeeding: Do not breastfeed during & for 1 week after treatment

As nirmatrelvir is co-administered with ritonavir, there may be a risk of HIV-1 developing resistance to HIV protease inhibitors in individuals with uncontrolled or undiagnosed HIV-1 infection.

Pregnancy and Lactation

Pregnancy

Nirmatrelvir and ritonavir is contraindicated during pregnancy.

The manufacturer advises that nirmatrelvir and ritonavir is not recommended during pregnancy and in women of childbearing potential not using effective contraception. At the time of writing there is no data from the use of nirmatrelvir and ritonavir during pregnancy. In animal studies there was no nirmatrelvir-related effect on foetal morphology or embryo-foetal viability at any dose.

A large number of pregnant woman were exposed to ritonavir during pregnancy (in combination therapy and not at therapeutic ritonavir dose used with nirmatrelvir). The data indicate no increase in the rate of birth defects compared to rates observed in population-based birth defect surveillance systems. Animal data with ritonavir have shown reproductive toxicity.

Lactation

Nirmatrelvir and ritonavir is contraindicated during breastfeeding.

The manufacturer recommends that breastfeeding should be discontinued during treatment with nirmatrelvir and ritonavir and for 7 days after the last dose. At the time of writing there is no human data on the use of nirmatrelvir and ritonavir during breastfeeding. It is unknown whether nirmatrelvir is excreted in human or animal breast milk. Effects on the breastfed newborn or infant is unknown. Limited published data reports that ritonavir is present in human milk.

Side Effects

Diarrhoea
Dysgeusia
Hepatitis
Increase of liver transaminases
Jaundice
Vomiting

Presentation

Oral formulation of nirmatrelvir and ritonavir.

Drugs List

Therapeutic Indications

Uses

Coronavirus disease 2019 (COVID-19) - treatment

Treatment of COVID-19 in adults who do not require supplemental oxygen and who are at increased risk for progression to severe COVID-19.

Dosage

Nirmatrelvir must be co-administered with ritonavir.

Treatment should be given as soon as possible after positive results of direct SARS-CoV-2 viral testing and within 5 days of onset of symptoms. If a patient requires hospitalisation due to severe or critical COVID-19 after starting treatment with nirmatrelvir and ritonavir, the patient should complete the full 5-day treatment course at the discretion of the patients healthcare provider.

Adults

Patients with Renal Impairment

Additional Dosage Information

Contraindications

Children under 18 years
Breastfeeding
Chronic renal failure
Galactosaemia
Pregnancy
Severe hepatic impairment
Severe renal impairment

Precautions and Warnings

Females of childbearing potential
Active liver disease
Glucose-galactose malabsorption syndrome
Hepatic enzymes abnormalities
Hepatitis
Lactose intolerance
Moderate renal impairment

Reduce dose in patients with moderate renal impairment
Contains polysorbate
Some formulations contain lactose
Monitor patients receiving concurrent anticoagulants
Advise patient to seek advice at first indications of pregnancy
Advise patient not to take St John's wort concurrently
Female: Ensure adequate contraception during treatment
Female: Use barrier contraception during and for 1 month after treatment
Breastfeeding: Do not breastfeed during & for 1 week after treatment

As nirmatrelvir is co-administered with ritonavir, there may be a risk of HIV-1 developing resistance to HIV protease inhibitors in individuals with uncontrolled or undiagnosed HIV-1 infection.

Pregnancy and Lactation

Pregnancy

Nirmatrelvir and ritonavir is contraindicated during pregnancy.

The manufacturer advises that nirmatrelvir and ritonavir is not recommended during pregnancy and in women of childbearing potential not using effective contraception. At the time of writing there is no data from the use of nirmatrelvir and ritonavir during pregnancy. In animal studies there was no nirmatrelvir-related effect on foetal morphology or embryo-foetal viability at any dose.

A large number of pregnant woman were exposed to ritonavir during pregnancy (in combination therapy and not at therapeutic ritonavir dose used with nirmatrelvir). The data indicate no increase in the rate of birth defects compared to rates observed in population-based birth defect surveillance systems. Animal data with ritonavir have shown reproductive toxicity.

Lactation

Nirmatrelvir and ritonavir is contraindicated during breastfeeding.

The manufacturer recommends that breastfeeding should be discontinued during treatment with nirmatrelvir and ritonavir and for 7 days after the last dose. At the time of writing there is no human data on the use of nirmatrelvir and ritonavir during breastfeeding. It is unknown whether nirmatrelvir is excreted in human or animal breast milk. Effects on the breastfed newborn or infant is unknown. Limited published data reports that ritonavir is present in human milk.

Side Effects

Diarrhoea
Dysgeusia
Hepatitis
Increase of liver transaminases
Jaundice
Vomiting

Overdosage

It is strongly recommended that the UK National Poisons Information Service be consulted on cases of suspected or actual overdose where there is doubt over the degree of risk or about appropriate management.

The following number will direct the caller to the relevant local centre (0844) 892 0111

Information may be obtained if you have access to ToxBase the primary clinical toxicology database of the National Poisons Information Service. This is available via password on the internet ( www.toxbase.org ) or if this is unavailable at the backup site ( www.toxbasebackup.org ).

Further Information

Last Full Review Date: January 2022

Reference Sources

Summary of Product Characteristics: Paxlovid 150mg/100mg film-coated tablets. Pfizer Limited. Revised January 2022.

NICE Evidence Services Available at: www.nice.org.uk Last accessed: 27 April 2022