Paxlovid: Pfizer, prescription, price, contraindications

the paxlovid It is a drug manufactured by the laboratory Pfizer to be administered orally (in tablets). The prescription it does at the first signs of infection COVID-19 to avoid serious forms. It is available from February 2022 in Francein pharmacies. On April 25, the High Health Authority (HAS) was pronounced in favor of reimbursement of this treatment. The characteristics of Paxlovid contraindications check before taking. This pharmacological treatment comes in addition to vaccination not “as a substitute”. Which is the composition Paxlovid? What indication? Its effectiveness against Covid? what is yours Reward ?Its side effects?

What is Paxlovid®?

American pharmaceutical company Pfizer developed antiviral Treatment, marketed under the name of paxlovid compound nirmatrelvir Y ritonavir. It comes in the form of tablets to be taken as soon as possible after the positive diagnosis of Covid-19 and maximum in 5 days following the onset of symptoms. This treatment targets the enzyme necessary for viral replication, 3C-like protease, and by inhibiting its action, blocks SARS-CoV-2 replication in the body. A Marketing Authorization (MA) was granted on January 28, 2022.

What are the indications of Paxlovid against Covid?

Paxlovid treatment is reserved for people at risk of severe forms of Covid-19. Must start in 5 days after the onset of Covid symptoms. To be eligible, the patient must meet all of the following criteria:

• Be at least 18 years old
• Have a positive SARS-CoV-2 test (RT-PCR or antigen)
• Appearance of first symptoms attributable to COVID-19 disease < 5 days
• Patient who does not require oxygen therapy for COVID-19
• Patient at high risk of progression to a severe form of COVID-191
• Absence of contraindication to treatment
• Risk of drug interactions evaluated and start of treatment considered possible by the prescriber
• Patient clearly informed of the procedures to implement this treatment

How to get Paxlovid in pharmacies?

The Paxlovid is the first treatment for Covid-19 available in the village pharmacies. It can be prescribed by general practitioners. from the February 3, 2022. Community pharmacies in the city in the presentation of the recipe mentioning the barcode that allows the pharmacist to ensure that the eligibility of the treatment has been validated by the prescribing physician. The order is made by the pharmacist after delivery of the prescription by the patient. Thus, to take into account the supply times and respect the taking of the drug in the 5 days following the onset of symptoms, it is necessary for the patient to go quickly to the community pharmacist after the medical consultation and the onset of symptoms.

How effective is it against Covid and against Omicron?

According to the High Health Authority, Paxlovid “retains antiviral activity in the different variants“. “The data available to evaluate the efficacy of this treatment have shown a reduced risk of progression to a severe form of Covid-19 (hospitalization or death) by approximately 85.2% after his administration. Additionally, Paxlovid’s mechanism of action gives hope of maintaining efficacy across the various variants, including Omicron. Indeed, preliminary in vitro data suggest that currently circulating variants of concern are amenable to treatment.

What is the composition of Paxlovid?

Paxlovid is made up of two molecules:

► The first PF-07321332 it is the active agent that prevents the virus protein from replicating.

► The second is ritonavir, a protease inhibitor, normally used for the treatment of HIV infections. “HIV is not related to coronaviruses and the replication of its genetic material occurs through a different mechanism. but produces He too a polyprotein that must be cut 9 times per a protease to form new viral particles“, explains an article published in the scientific journal Medicine Science in June 2020.

Paxlovid would prevent the coronavirus protease from replicating.

A protease is a virus-specific enzyme that acts on viral proteins to promote virus replication. Therefore, to stop the replication of a virus, it is necessary to reduce or prevent the protease from acting. Coronaviruses have two proteases, one of which is called SARS-CoV-2, 3CL. Paxlovid oral treatment acts on this protease.

What is the dose of Paxlovid?

The recommended dose of PAXLOVID® is 300mg PF-07321332 (2 tablets of 150 mg) and 100mg ritonavir (1 tablet of 100 mg), to be taken together (3 tablets totalorally, 2 times a day for 5 days). PAXLOVID can be taken with or without food. The tablets must be swallowed whole and must not be chewed, broken or crushed. It should be administered as soon as possible after obtaining a positive result in a direct virological screening test for SARS-CoV-2 (PCR or TAG) and no later than 5 days after the onset of symptoms.

What are the side effects of Paxlovid?

Among patients who participated in the Pfizer study published in November 2021 and who received Paxlovid, 1.7% experienced serious adverse events and had to discontinue treatment. The active ingredient in this medicine, ritonavir, can cause side effects such as:

• Diarrhea,
• nausea and vomiting
• abdominal pain
• sore throat or cough,
• headaches and dizziness
• skin rashes and itching
• alterations in the metabolism of sugars and fats with abnormal redistribution of fat seen after several months of treatment (called lipodystrophy)
• toxicity to the liver (increased transaminases) and the pancreas.

What are the contraindications of Paxlovid?

The antiviral is contraindicated in people with severe hepatic insufficiency or severe renal insufficiency (eGFR < 30 mL/min), including patients with end-stage renal disease on haemodialysis. Dose adjustment is necessary in patients with moderate renal insufficiency. Also, it's not Paxlovid is not recommended for use during pregnancy and in women of childbearing potential not using contraception. Breast-feeding should be discontinued during treatment with PAXLOVID® and, as a precaution, for 7 days after the end of treatment. The use of ritonavir may reduce the effectiveness of combined hormonal contraceptives. Patients using combined hormonal contraceptives should be advised to use an effective alternative method of contraception or an additional “barrier” method of contraception during PAXLOVID® treatment and until the menstrual cycle following discontinuation of PAXLOVID®.

What is the price of Paxlovid?

The price of the Paxlovid pill is unknown. However, Pfizer announced, in its press release, tiered pricing based on each country’s income level in order to guarantee equitable access for all and an affordable price. In other words, high- and upper-middle-income countries will pay more than low-income countries. PAXLOVID® specialty is distributed (PF-07321332 150 mg/ ritonavir 100 mg film-coated tablets) free health establishments and pharmacies. Therefore, the user benefits from this in a fully compatible way.

Is Paxlovid reimbursed?

On April 25, the HAS ruled in favor of reimbursement for this treatment. “It confirms the progress made by this medicine by giving you a level 3 improvement in actual benefit (ASMR). Registration for the reimbursement of this treatment should facilitate the prescription of Paxlovid® in community medicine and therefore its access to patients. In addition, general practitioners can rely on the Rapid Answers published by the HAS to prescribe this drug” specifies the authority in a press release.

Sources

– Covid-19: early access granted to Paxlovid® as a curative treatment. HAS. Press release January 21, 2022.

– PFIZER’S NEW ORAL COVID-19 ANTIVIRAL TREATMENT CANDIDATE REDUCED RISK OF HOSPITALIZATION OR DEATH BY 89% IN INTERIM ANALYSIS OF PHASE 2/3 EPIC-HR STUDY, November 5, 2021.

– Targeting the main protease of SARS-CoV-2 to make an effective drug against this coronavirus, Medicine Science, June 2020.