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0 0.25 0.5 0.75 1 1.25 1.5 1.75 2+ 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 Pfizer (DB RCT) 67% 0.33 [0.01-8.13] death 0/576 1/569 Dryden-Peterson 45% 0.55 [0.38-0.80] hosp. 40/6,036 232/24,286 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 Pandit 1% 0.99 [0.83-1.17] no recov. n/a n/a Tau​2 = 0.10, I​2 = 86.8%, p < 0.0001 Early treatment 44% 0.56 [0.47-0.68] 65/12,794 485/39,258 44% improvement Li 32% 0.68 [0.47-0.98] viral+ 40/83 130/224 Improvement, RR [CI] Treatment Control Tau​2 = 0.00, I​2 = 0.0%, p = 0.0025 Late treatment 32% 0.68 [0.47-0.98] 40/83 130/224 32% improvement Pfizer (DB RCT) 37% 0.63 [0.40-1.00] cases 986 (n) 985 (n) Improvement, RR [CI] Treatment Control Tau​2 = 0.00, I​2 = 0.0%, p = 0.05 Prophylaxis 37% 0.63 [0.40-1.00] 0/986 0/985 37% improvement All studies 38% 0.62 [0.53-0.73] 105/13,863 615/40,467 38% improvement Paxlovid COVID-19 studies Dec 2022 Tau​2 = 0.07, I​2 = 81.9%, p < 0.0001 Effect extraction pre-specified(most serious outcome) 1 OT: comparison with other treatment Favors paxlovid Favors control
Paxlovid COVID-19 studies. Pfizer has denied access to Paxlovid for an independent RCT [Ledford]. Recent:
Paxlovid has been officially adopted for early treatment in 7 countries. Submit updates/corrections.
Nov 15
Pandit et al., medRxiv, doi:10.1101/2022.11.14.22282195 (Preprint) 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 (Preprint) 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 (Preprint) 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/ (Preprint) (In Vitro) 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 (Preprint) 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 16
Dryden-Peterson et al., medRxiv, doi:10.1101/2022.06.14.22276393 (Preprint) Nirmatrelvir plus ritonavir for early COVID-19 and hospitalization in a large US health system
45% lower hospitalization [p=0.002]. IPW retrospective 30,322 age 50+ outpatients in the USA, showing lower hospitalization with paxlovid treatment.
Jun 14
Pfizer Press Release (News) 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 earlier 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 earlier 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 earlier 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 (News) Pfizer Shares Top-Line Results from Phase 2/3 EPIC-PEP Study of PAXLOVID™ for Post-Exposure Prophylactic Use
37% fewer cases [p=0.05]. PEP RCT showing lower risk of cases with treatment, without statistical significance. The group sizes and event counts have not been provided.
Apr 4
Ledford et al., Nature, doi:10.1038/d41586-022-00919-5 (News) African clinical trial denied access to key COVID drug Paxlovid
News reporting that Pfizer denied access to Paxlovid for an independent trial.
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] and 88% lower hospitalization [p<0.0001]. 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. NCT04960202.
Dec 14
Pfizer Press Release (News) 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 (Preprint) (In Vitro) 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 (Preprint) 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.
Oct 31
Zhong et al., Arteriosclerosis, Thrombosis, and Vascular Biology, doi:10.1161/01.atv.0000034707.40046.02 (In Vitro) 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.
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