Conv. Plasma
Nigella Sativa
Peg.. Lambda

Meta analysis
Home COVID-19 treatment researchPaxlovidPaxlovid (more..)
Melatonin Meta
Bromhexine Meta Metformin Meta
Budesonide Meta
Cannabidiol Meta Molnupiravir Meta
Colchicine Meta
Conv. Plasma Meta
Curcumin Meta Nigella Sativa Meta
Ensovibep Meta Nitazoxanide Meta
Famotidine Meta Paxlovid Meta
Favipiravir Meta Peg.. Lambda Meta
Fluvoxamine Meta Quercetin Meta
Hydroxychlor.. Meta Remdesivir Meta
Ivermectin Meta
Lactoferrin Meta

0 0.25 0.5 0.75 1 1.25 1.5 1.75 2+ EPIC-HR Hammond (DB RCT) 96% 0.04 [0.00-0.68] death 0/1,039 12/1,046 Improvement, RR [CI] Treatment Control Wong (PSM) 66% 0.34 [0.23-0.50] death 890 (n) 890 (n) Yip (PSW) 19% 0.81 [0.47-1.39] death/ICU Arbel 65+ 79% 0.21 [0.05-0.82] death Arbel 40-64 -32% 1.32 [0.16-10.8] death Najjar-Debbiny 46% 0.54 [0.39-0.75] severe case population-based cohort Pfizer (DB RCT) 67% 0.33 [0.01-8.13] death 0/576 1/569 Shao 20% 0.80 [0.71-0.91] viral time 17 (n) 114 (n) OT​1 Li (ES) 79% 0.21 [0.15-0.28] viral+ 18/175 130/224 Lu 12% 0.88 [0.78-0.98] viral+ n/a n/a Ganatra (PSM) 95% 0.05 [0.00-0.81] death 0/1,130 10/1,130 Shao 20% 0.80 [0.71-0.91] viral time 17 (n) 114 (n) OT​1 Zhong 15% 0.85 [0.65-1.13] recov. time 106 (n) 36 (n) Zhou (PSM) 73% 0.27 [0.13-0.58] death 7/2,808 100/10,849 Wong (PSM) 66% 0.34 [0.22-0.52] death Schwartz (PSW) 50% 0.50 [0.41-0.61] death population-based cohort Pandit 1% 0.99 [0.83-1.17] no recov. n/a n/a Bajema (PSM) 58% 0.42 [0.26-0.67] death 20/1,587 48.6/1,587 Dryden-Peterson 71% 0.29 [0.12-0.71] death Zheng (PSW) -4% 1.04 [0.56-1.93] death/hosp. 4,836 (n) 2,847 (n) OT​1 Evans 41% 0.59 [0.36-0.97] death/hosp. 602 (n) 4,973 (n) Liu (RCT) 38% 0.62 [0.21-1.86] death 5/132 8/132 Durstenfeld (PSW) -14% 1.14 [0.83-1.54] PASC 57/353 176/1,258 LONG COVID Lewnard 84% 0.16 [0.03-0.81] death/ICU n/a n/a Yan 31% 0.69 [0.30-1.58] death 7/73 17/122 Patel (PSM) 20% 0.80 [0.67-0.95] PASC 1,004 (n) 1,004 (n) Li -51% 1.51 [1.11-2.05] recov. time 9 (n) 11 (n) Park 5% 0.95 [0.57-1.62] death 940 (n) 1,567 (n) Wee 14% 0.86 [0.48-1.55] severe case population-based cohort Yang 2% 0.98 [0.95-1.00] death 220 (n) 1,061 (n) POSITIVES Edelstein -761% 8.61 [1.13-34.2] rebound 15/72 1/55 Kim 31% 0.69 [0.63-0.75] death population-based cohort Tau​2 = 0.07, I​2 = 90.2%, p < 0.0001 Early treatment 32% 0.68 [0.60-0.77] 129/16,586 503.6/29,589 32% lower risk Li 32% 0.68 [0.47-0.98] viral+ 40/83 130/224 Improvement, RR [CI] Treatment Control Wan 28% 0.72 [0.62-0.84] death 541/6,604 2,541/17,283 Shao 29% 0.71 [0.44-1.14] death 280 (n) 802 (n) Fu -280% 3.80 [0.41-35.4] ventilation 3/49 1/62 OT​1 Yu (RCT) -2% 1.02 [0.21-4.93] severe case 3/103 3/105 OT​1 Tau​2 = 0.00, I​2 = 0.0%, p < 0.0001 Late treatment 28% 0.72 [0.66-0.78] 587/7,119 2,675/18,476 28% lower risk Pfizer (DB RCT) 67% 0.33 [0.01-8.20] hosp. 0/830 1/840 Improvement, RR [CI] Treatment Control Tau​2 = 0.00, I​2 = 0.0%, p = 0.51 Prophylaxis 67% 0.33 [0.01-8.20] 0/830 1/840 67% lower risk All studies 28% 0.72 [0.64-0.80] 716/24,535 3,179.6/48,905 28% lower risk Paxlovid COVID-19 studies Sep 2023 Tau​2 = 0.06, I​2 = 88.6%, p < 0.0001 Effect extraction pre-specified(most serious outcome) 1 OT: comparison with other treatment Favors paxlovid Favors control
Pfizer has denied access to Paxlovid for independent RCTs Ledford. Pfizer RCTs report very good results, while non-Pfizer RCTs show relatively poor results Liu, Yu. Hoertel find that >50% of patients that died had a contraindication for Paxlovid. Retrospective studies that do not exclude contraindicated patients may significantly overestimate efficacy. Black box warning. The FDA notes that "severe, life-threatening, and/or fatal adverse reactions due to drug interactions have been reported in patients treated with paxlovid" FDA. Population studies often do not account for the different expected outcomes for the class of patients that seek out and receive early treatment. Recent:
Paxlovid has been officially adopted in 35 countries. Submit updates/corrections.
Aug 16
Yu et al., Phytomedicine, doi:10.1016/j.phymed.2023.155025 Efficacy and safety of Huashi Baidu granule plus Nirmatrelvir-Ritonavir combination therapy in patients with high-risk factors infected with Omicron (B.1.1.529): A multi-arm single-center, open-label, randomized controlled trial
2% higher severe cases (p=1), 6% lower hospital discharge (p=0.78), and 12% improved viral clearance (p=0.33). RCT 312 hospitalized COVID-19 patients in China, showing no significant difference between paxlovid and Huashi Baidu treatment. Combination therapy showed improved results to either treatment alone.
Jul 10
Kim et al., Journal of Korean Medical Science, doi:10.3346/jkms.2023.38.e211 Effectiveness of Paxlovid, an Oral Antiviral Drug, Against the Omicron BA.5 Variant in Korea: Severe Progression and Death Between July and November 2022
31% lower mortality (p<0.0001) and 43% lower severe cases (p<0.0001). Retrospective 1,936,925 COVID-19 patients in South Korea, showing lower mortality with paxlovid.
Jun 27
Edelstein et al., medRxiv, doi:10.1101/2023.06.23.23288598 SARS-CoV-2 virologic rebound with nirmatrelvir-ritonavir therapy
761% worse viral clearance (p=0.04). Prospective study of 127 COVID-19 patients in the USA showing higher risk of replication-competent virologic rebound with paxlovid treatment. Authors note that rebound substantially increases the duration of shedding of replication-compet..
Jun 26
Fu et al., Authorea, Inc., doi:10.22541/au.168777909.90198442/v1 Comparison of the Different Medications for COVID-19 in Kidney Transplant Recipients
280% higher ventilation (p=0.32), 659% higher ICU admission (p=0.04), and 207% higher progression (p=0.005). Retrospective 140 kidney transplant patients, showing higher risk of AKI with paxlovid compared with azavudine. There were more severe cases in the paxlovid group at baseline.
Jun 22
Yang et al., Elsevier BV, doi:10.2139/ssrn.4488145 Clinical Prognosis and Risk Factors of Death for Covid-19 Patients Complicated with Coronary Heart Disease/Diabetes/Hypertension-A Retrospective, Real-World Study
2% lower mortality (p=0.04). Retrospective 1,281 COVID-19 patients with comorbidities in China, showing 2% lower mortality with paxlovid.
Jun 17
Wee et al., Clinical Microbiology and Infection, doi:10.1016/j.cmi.2023.06.016 Real-world effectiveness of nirmatrelvir/ritonavir against COVID-19 hospitalisations and severe COVID-19 in community-dwelling elderly Singaporeans during Omicron BA.2, BA.4/5 and XBB transmission
14% lower severe cases (p=0.63) and 35% lower hospitalization (p=0.002). Retrospective 3,959 paxlovid patients and 139,379 untreated controls, showing lower hospitalization with treatment. Contraindicted patients were excluded.
Jun 16
Park et al., Research Square, doi:10.21203/ The association of mortality with vaccination and underlying disease among COVID-19 patients in long term care hospitals at Daegu and Gyeonsangbuk-do in Korea
5% lower mortality (p=0.86). Retrospective 2,507 COVID-19 patients at 18 long term care hospitals with COVID-19 outbreaks in Korea, showing no significant difference in mortality with paxlovid treatment. Note that this study is less affected by the typical confoundin..
May 14
Shao et al., medRxiv, doi:10.1101/2023.05.10.23289325 Composite interventions on outcomes of severely and critically ill patients with COVID-19 in Shanghai, China
29% lower mortality (p=0.16) and 28% worse recovery (p<0.0001). Retrospective 1,082 hospitalized COVID-19 patients in China, showing lower mortality and worse quality of life with paxlovid.
May 10
Torti et al., Elsevier BV, doi:10.2139/ssrn.4444431 Real-Life Comparison of Mortality in Non-Hospitalised Patients with SARS-CoV-2 Infection at Risk for Clinical Progression Treated with Molnupiravir or Nirmatrevir Plus Ritonavir During the Omicron Era in Italy: A Nationwide, Observational Study
32% lower mortality (p=0.0001). Prospective study of 17,977 outpatients treated with molnupiravir and 11,576 treated with paxlovid, showing significant mortality with both treatments, and lower mortality with paxlovid.
Apr 25
Li et al., Frontiers in Pediatrics, doi:10.3389/fped.2023.1160929 Clinical efficacy analysis of paxlovid in children with hematological diseases infected with the omicron SARS-CoV-2 new variant
51% worse recovery (p=0.008) and 58% faster viral clearance (p=0.03). Retrospective 20 pediatric hematological disease patients in China, showing faster viral clearance with paxlovid, but slower resolution of fever.
Apr 6
Patel et al., medRxiv, doi:10.1101/2023.04.05.23288196 Incidence of Symptoms Associated with Post-Acute Sequelae of SARS-CoV-2 infection in Non-Hospitalized Vaccinated Patients Receiving Nirmatrelvir-Ritonavir
20% lower PASC (p=0.01). TriNetX retrospective 1,004 paxlovid patients and matched controls, showing lower risk of PASC with treatment.
Mar 23
Igho-Osagie et al., Clinical Therapeutics, doi:10.1016/j.clinthera.2023.03.012 Prevalence of Potential Drug-Drug Interactions with Ritonavir-Containing COVID-19 therapy in the United States: An Analysis of the National Health and Nutrition Examination Survey
Analysis of 15,685 adults in the USA estimating that 29.3% of the population risk a major or contraindicated drug interaction with paxlovid, which may increase significantly for patients over 60 or with several comorbidities that also inc..
Mar 22
Yan et al., Frontiers in Pharmacology, doi:10.3389/fphar.2023.1147980 Nirmatrelvir/ritonavir for patients with SARS-CoV-2 infection and impaired kidney function during the Omicron surge
31% lower mortality (p=0.5), 44% lower progression (p=0.04), 14% lower ICU admission (p=0.61), and 9% shorter hospitalization (p=0.03). Retrospective 195 patients with impaired kidney function in China, showing lower combined mortality/ICU/cardiovascular events, and improved viral clearance with paxlovid.
Mar 15
Lewnard et al., The Lancet Infectious Diseases, doi:10.1016/S1473-3099(23)00118-4 Effectiveness of nirmatrelvir–ritonavir in preventing hospital admissions and deaths in people with COVID-19: a cohort study in a large US health-care system
84% lower combined mortality/ICU admission (p=0.03) and 54% lower combined mortality/hospitalization (p=0.03). Retrospective 7,274 outpatients in the USA treated with paxlovid and matched controls, showing lower combined hospitalization/death with treatment. With a small percentage of eligible patients receiving treatment, confounding by indicatio..
Mar 13
Kim et al., Proceedings of the National Academy of Sciences, doi:10.1073/pnas.2221857120 Computational prediction of interactions between Paxlovid and prescription drugs
In Silico analysis of drug–drug interactions for paxlovid. From 2,248 prescription drugs, 1,628 were predicted to have 2,445 interactions with nirmatrelvir and/or ritonavir (673 for nirmatrelvir and 1,403 ritonavir). For 873 drugs, author..
Mar 5
Durstenfeld et al., medRxiv, doi:10.1101/2023.03.02.23286730 Association of Nirmatrelvir/Ritonavir Treatment with Long COVID Symptoms in an Online Cohort of Non-Hospitalized Individuals Experiencing Breakthrough SARS-CoV-2 Infection in the Omicron Era
14% higher PASC (p=0.4). Retrospective 4,684 COVID+ patients mostly in the USA, 988 treated with paxlovid, showing higher odds of long COVID with treatment, without statistical significance.
Feb 22
Wan et al., Journal of Infection, doi:10.1016/j.jinf.2023.02.029 Molnupiravir and nirmatrelvir-ritonavir reduce mortality risk during post-acute COVID-19 phase
28% lower mortality (p<0.0001), 24% lower hospitalization (p<0.0001), and 18% lower progression (p<0.0001). Retrospective 30,040 hospitalized patients in Hong Kong, showing lower mortality with paxlovid treatment. Patients with contraindications to paxlovid were not excluded.
Feb 10
Kuroda et al., Journal of Antimicrobial Chemotherapy, doi:10.1093/jac/dkad027 Efficacy comparison of 3CL protease inhibitors ensitrelvir and nirmatrelvir against SARS-CoV-2 in vitro and in vivo
In Vitro and animal study comparing nirmatrelvir and ensitrelvir, showing similar efficacy in vitro, and equal or better efficacy of ensitrelvir in vivo (with similar unbound-drug plasma concentrations).
Feb 9
Aggarwal et al., The Lancet Infectious Diseases, doi:10.1016/S1473-3099(23)00011-7 Real-world use of nirmatrelvir–ritonavir in outpatients with COVID-19 during the era of omicron variants including BA.4 and BA.5 in Colorado, USA: a retrospective cohort study
Retrospective 28,167 patients in the USA demonstrating confounding. The large difference shown in Figure 1 at day 0 indicates that the groups are not comparable (32 control hospitalizations versus 0 for paxlovid at day 0) and suggests imm..
Feb 5
Liu et al., The Lancent Regional Health, doi:10.1016/j.lanwpc.2023.100694 Efficacy and safety of Paxlovid in severe adult patients with SARS-Cov-2 infection: a multicenter randomized controlled study
38% lower mortality (p=0.57), 67% higher ventilation (p=0.44), 10% longer ICU admission (p=0.8), and 27% higher progression (p=0.58). RCT 264 patients in China, showing no significant difference in outcomes with paxlovid.
Jan 25
Evans et al., Journal of Infection, doi:10.1016/j.jinf.2023.02.012 Real-world effectiveness of molnupiravir, nirmatrelvir-ritonavir, and sotrovimab on preventing hospital admission among higher-risk patients with COVID-19 in Wales: A retrospective cohort study
41% lower combined mortality/hospitalization (p=0.04). Retrospective high risk outpatients in the UK, showing lower hospitalization/death with paxlovid treatment. Residual confounding is likely with adjustments having no detail on specific comorbidities. Patients with contraindications for pa..
Jan 22
Zheng et al., medRxiv, doi:10.1101/2023.01.20.23284849 Comparative effectiveness of Paxlovid versus sotrovimab and molnupiravir for preventing severe COVID-19 outcomes in non-hospitalised patients: observational cohort study using the OpenSAFELY platform
4% higher combined mortality/hospitalization (p=0.91). OpenSAFELY retrospective 7,683 outpatients in the UK, showing no significant difference in hospitalization/death between paxlovid and sotrovimab.
Jan 11
Heilmann et al., Science Translational Medicine, doi:10.1126/scitranslmed.abq7360 SARS-CoV-2 3CLpro mutations selected in a VSV-based system confer resistance to nirmatrelvir, ensitrelvir, and GC376
In Vitro and In Silico study showing selection of resistant mutations with nirmatrelvir use. Several mutations were identified that confer resistance to 3CLpro inhibitors nirmatrelvir, ensitrelvir, and GC376. Authors note that most of the..
Jan 10
Jochmans et al., mBio, doi:10.1128/mbio.02815-22 The Substitutions L50F, E166A, and L167F in SARS-CoV-2 3CLpro Are Selected by a Protease Inhibitor In Vitro and Confer Resistance To Nirmatrelvir
In Vitro study showing selection of nirmatrelvir-resistant mutations with a protease inhibitor.
Dec 13
Dryden-Peterson et al., Annals of Internal Medicine, doi:10.7326/M22-2141 (date from preprint) Nirmatrelvir Plus Ritonavir for Early COVID-19 in a Large U.S. Health System
71% lower mortality (p=0.006), 44% lower combined mortality/hospitalization (p=0.0001), and 40% lower hospitalization (p=0.001). IPW retrospective 44,551 outpatients age 50+ in the USA, showing lower mortality and hospitalization with paxlovid treatment.
Dec 6
Bajema et al., medRxiv, doi:10.1101/2022.12.05.22283134 Effectiveness of COVID-19 treatment with nirmatrelvir-ritonavir or molnupiravir among U.S. Veterans: target trial emulation studies with one-month and six-month outcomes
58% lower mortality (p=0.0004), 56% lower ICU admission (p=0.03), and 7% lower hospitalization (p=0.53). Retrospective 112,380 high-risk patients in the USA, showing lower mortality with paxlovid treatment. The title and headers of Table S14 are conflicting but the data appears to match the title.
Nov 15
Hoertel et al., JAMA Network Open, doi:10.1001/jamanetworkopen.2022.42140 Prevalence of Contraindications to Nirmatrelvir-Ritonavir Among Hospitalized Patients With COVID-19 at Risk for Progression to Severe Disease
Retrospective 62,525 hospitalized COVID-19 patients in France, showing that over 50% of patients that died had a contraindication for the use of Paxlovid. Retrospective studies that do not exclude contraindicated patients may significantl..
Nov 15
Pandit et al., medRxiv, doi:10.1101/2022.11.14.22282195 The Paxlovid Rebound Study: A Prospective Cohort Study to Evaluate Viral and Symptom Rebound Differences Between Paxlovid and Untreated COVID-19 Participants
1% improved recovery (p=0.9), 3% improved viral clearance (p=0.73), and 171% worse results (p=0.06). Prospective study of 170 COVID-19 patients in the USA, showing no significant difference in symptomatic and viral recovery times, and higher risk of symptomatic rebound, without statistical significance. There were more elderly patients i..
Nov 5
Schwartz et al., medRxiv, doi:10.1101/2022.11.03.22281881 Real-world effectiveness of nirmatrelvir/ritonavir use for COVID-19: A population-based cohort study in Ontario, Canada
50% lower mortality (p<0.0001) and 43% lower combined mortality/hospitalization (p<0.0001). Retrospective 177,545 patients in Canada, 8,876 treated with paxlovid, showing lower mortality and hospitalization with treatment, and declining efficacy over the two time periods analyzed.
Oct 8
Wong et al., The Lancet, doi:10.1016/S0140-6736(22)01586-0 Real-world effectiveness of molnupiravir and nirmatrelvir plus ritonavir against mortality, hospitalisation, and in-hospital outcomes among community-dwelling, ambulatory patients with confirmed SARS-CoV-2 infection during the omicron wave in Hong Kong: an observational study
66% lower mortality (p<0.0001), 38% lower ventilation (p=0.36), 58% higher ICU admission (p=0.08), and 24% lower hospitalization (p<0.0001). PSM retrospective 1,074,856 outpatients in Hong Kong, showing lower mortality and hospitalization with paxlovid.
Sep 14
Zhou et al., medRxiv, doi:10.1101/2022.09.13.22279908 Real-World Effectiveness of Nirmatrelvir/Ritonavir in Preventing Hospitalization Among Patients With COVID-19 at High Risk for Severe Disease in the United States: A Nationwide Population-Based Cohort Study
73% lower mortality (p<0.0001) and 84% lower hospitalization (p<0.0001). Pfizer retrospective 2,811 high risk COVID-19 patients treated with paxlovid in the US, and 10,849 matched controls, showing lower risk of mortality and hospitalization with treatment.
Sep 6
Zhong et al., Frontiers in Medicine, doi:10.3389/fmed.2022.980002 The efficacy of paxlovid in elderly patients infected with SARS-CoV-2 omicron variants: Results of a non-randomized clinical trial
15% faster recovery (p=0.26) and 16% faster viral clearance (p=0.009). Retrospective 106 paxlovid and 36 control patients in China, showing faster viral clearance with treatment.
Aug 28
Shao et al., Vaccines, doi:10.3390/vaccines10091409 Clinical Progression and Outcome of Hospitalized Patients Infected with SARS-CoV-2 Omicron Variant in Shanghai, China
20% faster viral clearance (p=0.0006). Retrospective 226 patients in China, showing faster viral clearance with paxlovid. Age range and severity differed between groups.
Aug 20
Ganatra et al., Clinical Infectious Diseases, doi:10.1093/cid/ciac673 Oral Nirmatrelvir and Ritonavir in Non-hospitalized Vaccinated Patients with Covid-19
95% lower mortality (p=0.002), 39% lower progression (p=0.0001), and 56% lower hospitalization (p=0.02). TriNetX retrospective 1,131 vaccinated COVID-19 patients treated with paxlovid and matched controls, showing lower mortality and hospitalization with treatment.
Aug 9
de Oliveira et al., Research Square, doi:10.21203/ H172Y mutation perturbs the S1 pocket and nirmatrelvir binding of SARS-CoV-2 main protease through a nonnative hydrogen bond
In Silico and In Vitro study of the H172Y mutation which significantly reduces paxlovid's inhibitory activity. Monotherapy with paxlovid and selective pressure may favor resistance mutations.
Aug 4
Lu et al., Emerging Microbes & Infections, doi:10.1080/22221751.2022.2109517 Geriatric risk and protective factors for serious COVID-19 outcomes among older adults in Shanghai Omicron wave
12% improved viral clearance (p=0.02). Retrospective 1,377 patients in China, showing significantly faster viral clearance with Paxlovid. Authors analyze progression to severe/critical disease, but do not provide results for Paxlovid.
Jul 23
Li et al., Clinical Infectious Diseases, doi:10.1093/cid/ciac600 Association of nirmatrelvir/ritonavir treatment on upper respiratory SARS-CoV-2 RT-PCR negative conversion rates among high-risk patients with COVID-19
79% improved viral clearance (p<0.0001). Retrospective 258 paxlovid patients and 224 patients before paxlovid was available in China, showing significantly faster viral clearance with treatment. Adjusted results are only provided for subgroups (≤5, >5 days from onset). Patients ..
Jul 6
Shao et al., medRxiv, doi:10.1101/2022.07.03.22277169 Clinical advancement of patients infected with SARS-CoV-2 Omicron variant in Shanghai, China
20% faster viral clearance (p=0.0006). Retrospective 17 paxlovid and 114 lianhuaqingwen patients in China, showing faster viral clearance with paxlovid.
Jun 14
Pfizer Press Release Pfizer announces additional phase 2/3 study results confirming robust efficacy of novel COVID-19 oral antiviral treatment candidate in reducing risk or hospitalization or death
86% lower ICU admission (p=0.12) and 51% lower combined mortality/hospitalization (p=0.2). EPIC-SR update reporting that the primary endpoint was not met. Minimal details are provided.
Jun 2
Najjar-Debbiny et al., Clinical Infectious Diseases, doi:10.1093/cid/ciac443 Effectiveness of Paxlovid in Reducing Severe COVID-19 and Mortality in High Risk Patients
46% lower severe cases (p=0.0002). Retrospective 180,351 patients in Israel, 4,737 treated with paxlovid, showing significantly lower combined severe COVID-19 / mortality with treatment.
Jun 1
Arbel et al., New England Journal of Medicine, doi:10.1056/NEJMoa2204919 (date from preprint) Nirmatrelvir Use and Severe Covid-19 Outcomes during the Omicron Surge
79% lower mortality (p=0.03) and 73% lower hospitalization (p<0.0001). Retrospective 109,254 patients in Israel, 3,902 treated with nirmatrelvir, showing lower mortality and hospitalization with treatment for the subgroup of patients >65. Authors only provide subgroup results.
May 24
Yip et al., Clinical Infectious Diseases, doi:10.1093/cid/ciac687 (date from preprint) Impact of the use of oral antiviral agents on the risk of hospitalization in community COVID-19 patients
19% lower combined mortality/ICU admission (p=0.45) and 21% lower hospitalization (p=0.01). Propensity score weighted retrospective of 93,883 outpatients in Hong Kong, 5,808 treated with molnupiravir and 4,921 treated with paxlovid, showing higher hospitalization and higher combined mortality/mechanical ventilation/ICU admission..
May 20
Wong et al., The Lancet Infectious Diseases, doi:10.1016/S1473-3099(22)00507-2 (date from preprint) Real-world effectiveness of early molnupiravir or nirmatrelvir–ritonavir in hospitalised patients with COVID-19 without supplemental oxygen requirement on admission during Hong Kong's omicron BA.2 wave: a retrospective cohort study
66% lower mortality (p<0.0001), 3% lower ventilation (p=0.96), 43% lower progression (p<0.0001), and 4% shorter hospitalization (p=0.32). PSM retrospective 40,776 patients in Hong Kong, showing lower mortality and lower combined mortality, ventilation, ICU, and oxygen therapy with paxlovid treatment.
Apr 29
Pfizer News Release Pfizer Shares Top-Line Results from Phase 2/3 EPIC-PEP Study of PAXLOVID™ for Post-Exposure Prophylactic Use
25% lower severe cases (p=0.42), 15% lower progression (p=0.2), and 36% fewer symptomatic cases (p=0.12). PEP RCT showing lower risk of cases with treatment, without statistical significance. Results from [].
Apr 4
Ledford et al., Nature, doi:10.1038/d41586-022-00919-5 African clinical trial denied access to key COVID drug Paxlovid
News reporting that Pfizer denied access to Paxlovid for an independent trial. The press release indicates that Pfizer has denied access for multiple groups [ANTICOV]. Also see [].
Mar 15
ANTICOV Press Release Pfizer blocking research to generate evidence on optimal use of novel antiviral for COVID-19 patients in low- and middle-income countries
ANTICOV reports that Pfizer has denied access to paxlovid for studies proposed by multiple groups. Also see [Ledford].
Feb 16
Hammond et al., New England Journal of Medicine, doi:10.1056/NEJMoa2118542 Oral Nirmatrelvir for High-Risk, Nonhospitalized Adults with Covid-19
96% lower mortality (p=0.0005), 88% lower hospitalization (p<0.0001), 11% higher progression (p=0.45), and 21% faster recovery (p=0.0003). EPIC-HR RCT, 1,039 higher risk patients treated with paxlovid (PF-07321332 + ritonavir) and 1,046 control patients, showing significantly lower mortality and hospitalization with treatment.
Dec 14
Pfizer Press Release Pfizer announces additional phase 2/3 study results confirming robust efficacy of novel COVID-19 oral antiviral treatment candidate in reducing risk or hospitalization or death
70% lower hospitalization (p=0.05). EPIC-SR trial interim results, 428 patients treated with paxlovid (PF-07321332 + ritonavir) and 426 control patients, showing lower hospitalization with treatment. NCT05011513.
Nov 30
Ullrich et al., bioRxiv, doi:10.1101/2021.11.28.4702264 Main protease mutants of SARS-CoV-2 variants remain susceptible to PF-07321332
In Vitro study showing that PF-07321332 maintains efficacy against variants C.37 lambda, B.1.1.318, B.1.2, B.1.351 beta, and P.2 zeta.
Nov 5
Abdelnabi et al., bioRxiv, doi:10.1101/2021.11.04.467077 The oral protease inhibitor (PF-07321332) protects Syrian hamsters against infection with SARS-CoV-2 variants of concern
In Vitro and hamster study showing paxlovid component PF-07321332 effective against four variants of concern, inibits replication of the alpha variant in primary human airway epithelial cells, protected Syrian hamsters against intranasal ..
Jul 30
Tang et al., International Journal of Clinical Pharmacy, doi:10.1007/s11096-021-01311-5 Drug-induced liver injury associated with lopinavir-ritonavir in patients with COVID-19: a disproportionality analysis of U.S. food and drug administration adverse event reporting system (FAERS) data
Disproportionality analysis showing higher risk of liver injury with lopinavir/ritonavir for COVID-19 patients. Paxlovid combines nirmatrelvir and ritonavir.
Aug 22
Zhong et al., Arteriosclerosis, Thrombosis, and Vascular Biology, doi:10.1161/01.atv.0000034707.40046.02 HIV Protease Inhibitor Ritonavir Induces Cytotoxicity of Human Endothelial Cells
In Vitro study showing that ritonavir (part of paxlovid) can cause endothelial mitochondrial DNA damage and cell death at concentrations near clinical plasma levels.
Please send us corrections, updates, or comments. Vaccines and treatments are complementary. All practical, effective, and safe means should be used based on risk/benefit analysis. No treatment, vaccine, or intervention is 100% available and effective for all current and future variants. We do not provide medical advice. Before taking any medication, consult a qualified physician who can provide personalized advice and details of risks and benefits based on your medical history and situation. FLCCC and WCH provide treatment protocols.
  or use drag and drop   
Thanks for your feedback! Please search before submitting papers and note that studies are listed under the date they were first available, which may be the date of an earlier preprint.