Here’s what we know about FDA-authorized COVID-19 antivirals

While FDA has authorized two COVID-19 antiviral medications—Paxlovid from Pfizer and molnupiravir Merck, Americans may not have the easiest time accessing these medications, which are aimed at preventing hospitalizations deaths in high-risk patients. At press time, Paxlovid will only be available a limited number of pharmacies. Patients need prescription specific licensed health care providers to get medications. PREP Act authority allows pharmacists order dispense therapeutics, including oral subcutaneous medication, specifically prevents writing prescriptions for anti-virals. In statement, APhA noted that antivirals most effective when taken early infection. “Requiring patients make an appointment with another prescriber just their pharmacist fill adds cost, inconvenience but concerning all, it could cause even deaths. The ability pharmacies one-stop-shop testing, patient assessment, ordering, dispensing would game-changer timely access needed treatments—just as been administration COVID vaccines,” stated APhA. late December 2021, issued EUA Merck medications treat mild moderate risk progression severe Neither medication is pre- or postexposure prophylaxis, nor should used COVID-19, who hospitalized. Both started soon possible after diagnosis within 5 days symptom onset. See chart below on how compare. Pfizer’s dosed nirmatrelvir 150 mg tablets one 100 ritonavir tablet by mouth, twice daily, days. Nirmatrelvir inhibits SARS-CoV-2 replication while works slowing breakdown nirmatrelvir. use 12 years older weigh least 40 kg received positive diagnosis. Dosing decreased compromised renal function there drug–drug interactions avoid. Tabled 1Comparison COVID-19CharacteristicPaxlovid (Pfizer)Molnupiravir (Merck)Efficacy patients89%30%Deaths placebo vs. drug7 09 0Duration therapyPaxlovid 300 + Ritonavir BID x days800 daysDrug (CYP3A)Yes, statins, blood thinnersMinimalRepurposed?No, specific; adapted anti-SARS moleculeYes, equine encephalitis treatment; planned test RSV*Mpro, main protease; RSV, respiratory syncytial virus./influenzaMechanism actionInhibits Mpro,*Mpro, virus. mutagenicNucleoside analog; induces mutationsPregnancy considerationsNo informationNot recommendedAdverse effects20% either pill experienced adverse events, mostly mild12% receiving 11% medication-related eventsContraindicationsHistory clinically significant hypersensitivity reactions any active inactive componentsCoadministration drugs highly dependent upon CYP3A clearance elevated concentrations associated serious reactionsCoadministration potent inducersNo contraindications identified based dataPrice per patient~$500 course~$700 course* Mpro, Open table new tab Merck’s supplied 200 capsule. It 4 capsules Molnupiravir introducing errors into genetic code. 18 because also inhibit bone cartilage growth. 1Selected developmentDrugCompanyDeliveryStatusOriginRdRp*EBV, Ebola virus; HBV, hepatitis B RdRp, RNA-dependent RNA polymerase; VEEV, Venezuelan inhibitorsRemdesivirGileadI.V.ApprovedRepurposed EBV*EBV, candidateMolnupiravirMerck & Co.OralEUA submittedRepurposed VEEV*EBV, candidateClevudineBukwangOralPhase IIRepurposed HBV*EBV, drugJGL-2020Gilead/JubilantOralPhase I doneOral remdesivirODBG-P-RVnUC San DiegoOralPreclinicalOral remdesivirGS-621763Gilead/Georgia State UniversityOralPreclinicalOral remdesivirMpro*EBV, inhibitorsPF-07321332 (Paxlovid)PfizerOralEUA submittedSARS-CoV-2 optimizedS-217622ShionogiOralPhase IIISARS-CoV-2 optimizedPF-07304814Pfizer IVPhase doneSARS-CoV-1 candidate prodrugPBI-0451PardesOralPhase ISARS-CoV-2 optimizedEDP-235EnantaOralPhase plannedSARS-CoV-2 optimized13bUniversity LübeckInhaledPreclinicalSARS-CoV-2 optimized* EBV, whom alternative treatment options accessible appropriate. Similar pipeline safety efficacy profiles (see above). ISMP issues warning about newly antiviralTo encourage appropriate drug nirmatrelvir/ritonavir (Paxlovid), Institute Safe Medication Practices (ISMP) released alert pharmacists.ISMP dose reduction necessary impairment, impairment receive drug.Paxlovid, federal government, designed viral testing results high disease.The carton containing blister cards, each daily morning evening doses comprising ritonavir. For remove both card before being dispensed. empty blisters all cards covered manufacturer-supplied stickers.ISMP said other include failing take together. Providers report organizations FDA’s MedWatch reporting program, mandatory products under EUA. requests its error program. To pharmacists. drug. Paxlovid, disease. stickers.