What is the difference between azivudine, monogravir and nematvir/ritonavir?💫💫💫

Azivudine, monogravir and nematvir/ritonavir are all clinical drugs used to treat the new coronavirus. What's the difference between them? 

What is the anti-coronavirus mechanism?

The new coronavirus is composed of RNA and protein. The raw material for RNA synthesis is cytosine nucleoside. Azivudine and monogravir are cytosine nucleoside analogs. They will synthesize poor RNA with the new coronavirus and inhibit the replication of the virus. Nematvir is a peptidomimetic substance. It will prevent the virus from synthesizing functional proteins by inhibiting 3C-like protease, and the replication of the virus will be inhibited. Although ritonavir has no effect against the new coronavirus, it will inhibit the elimination of nematvir and enhance its effect.

What are the properties of azivudine, monogravir and nematvir/ritonavir?

Due to their different chemical structures, they have different adverse reactions and metabolic processes in the body. 

Bone and Cartilage Toxicity: In trials, rats were repeatedly dosed with monogravir, which caused toxicity to the bones and cartilage of rats. Therefore, monogravir may affect bone and cartilage development in children.

Dosage in Patients with Hepatic or Renal Impairment: Monolavir is not eliminated primarily through the liver or kidneys, so no dose adjustment is required in patients with hepatic or renal impairment.

Drug interactions:

• Azivudine: Caution is required when combined with amiodarone, colchicine, dabigatran, digoxin, dronedarone, voriconazole, grapefruit juice, etc.
• Monolavir: Due to limited available data, no drug interactions have been found.
• Nematvir/ritonavir: These interact with many medicines.

What are the treatment differences between azivudine, monogravir, and nematvir/ritonavir?

Azivudine: It is mainly used to treat adult patients with characteristic pneumonia manifestations of new coronavirus infection visible on imaging (moderate infection). It is not intended for use in pregnant or breastfeeding women. If Azivudine is used, breastfeeding should be discontinued during treatment and for 4 days after treatment.

Monolavir: It is indicated for the treatment of adult patients with mild or moderate infections within five days of onset and who are at high risk for progression to severe disease. It has fetal toxicity similar to that of azivudine. If monogravir is used, breastfeeding should be discontinued during treatment and for 4 days after the end of treatment.

Nematrevir/ritonavir: Same indications as monogravir. However, it may still be used when the potential benefit to the mother outweighs the potential risk to the fetus. If nematvir/ritonavir is used, breastfeeding should be discontinued during treatment and for 7 days after the end of treatment.

What are the dosages of azivudine, monogravir, and nematvir/ritonavir?

Azivudine: If taken after meals, its absorption rate and total amount will be increased. Changes in drug concentration in the blood will also increase, thereby increasing the risk of adverse reactions. Its recommended usage is to take it orally once on an empty stomach before going to bed, 5mg each time (generally each tablet is 1mg, 5 pills taken orally each time), and the course of treatment should not exceed 14 days.

Monolavir: Take on an empty stomach or with food, once every 12 hours, 0.8g each time (usually 0.2g per tablet, 4 tablets taken orally each time) for 5 consecutive days.

Nematrevir/ritonavir: Take on an empty stomach or with food, once every 12 hours, 300 mg of nematvir (each tablet is 150 mg, 2 tablets taken orally each time) and 100 mg of ritonavir ( Each tablet is 100mg, 1 tablet taken orally at a time), taken continuously for 5 days.

What are the adverse reactions of azivudine, monogravir, and nematvir/ritonavir?

Azivudine: Common adverse reactions include diarrhea, increased transaminases, increased breathing, and occasionally increased the level of blood glucose. It may cause moderate to severe damage to the liver, so patients with moderate to severe liver damage should use it with caution.

Monolavir: Common adverse reactions include diarrhea, nausea, dizziness, and occasionally rash and urticaria.

Nematrevir/ritonavir: Common adverse reactions include diarrhea and taste problems, and occasionally elevated transaminases. It may cause severe liver damage and is therefore contraindicated in patients with severe hepatic impairment.

Additionally, they can affect fertility. Therefore, it recommends the use of effective contraception during and for 4 days after treatment with azivudine and monogravir, and the use of effective contraception during and for 7 days after treatment with nematvir/ritonavir.