Casirivimab/imdevimab COVID-19 studies. Efficacy is variant dependent. In Vitro studies suggest a lack of efficacy for omicron [Liu, Sheward, Tatham, VanBlargan]. Monoclonal antibody use with variants can be associated with prolonged viral loads, clinical deterioration, and immune escape [Choudhary]. ADE shown In Vitro [Shimizu].
Recent:Shimizu Hussein Gershengorn Planas.
Casirivimab/imdevimab has been officially adopted
in 42 countries.
Submit updates/corrections .
Mar 30 |
(Preprint) (meta analysis) | Casirivimab/imdevimab for COVID-19: real-time meta analysis of 26 studies |
| Statistically significant improvements are seen for mortality, hospitalization, progression, recovery, cases, and viral clearance. 19 studies from 13 independent teams in 4 different countries show statistically significant improvements.. | ||
Dec 19 |
et al., BMJ Open, doi:10.1136/bmjopen-2022-064953 | Real-world effectiveness of casirivimab and imdevimab among patients diagnosed with COVID-19 in the ambulatory setting: a retrospective cohort study using a large claims database |
| 60% lower combined mortality/hospitalization [p<0.0001]. Retrospective 73,759 outpatients treated with casirivimab/imdevimab, showing lower mortality with treatment. This result is subject to potentially substantial confounding by indication - patients with more severe cases may be more likely .. | ||
Dec 2 |
et al., PLOS ONE, doi:10.1371/journal.pone.0278770 | The clinical effectiveness of REGEN-COV in SARS-CoV-2 infection with Omicron versus Delta variants |
| 95% higher hospitalization [p=0.09]. Retrospective 2,083 outpatients in the USA, showing higher risk of hospitalization with casirivimab/imdevimab, without statistical significance. There may be significant unadjusted confounding by indication. | ||
Nov 17 |
et al., bioRxiv, doi:10.1101/2022.11.17.516888 (Preprint) (In Vitro) | Resistance of Omicron subvariants BA.2.75.2, BA.4.6 and BQ.1.1 to neutralizing antibodies |
| In Vitro study suggesting a lack of efficacy for casirivimab/imdevimab with BA.2.75.2 and BQ.1.1. | ||
Oct 15 |
et al., American Journal of Health-System Pharmacy, doi:10.1093/ajhp/zxac295 | The impact of COVID-19 monoclonal antibodies on clinical outcomes: A retrospective cohort study |
| 61% higher mortality [p=0.4], 51% higher ICU admission [p=0.5], 49% lower hospitalization [p<0.0001], and 39% lower progression [p<0.0001]. PSM retrospective 1,344 patients in the USA, showing lower hospitalization with monoclonal antibody treatment. Authors combine patients treated with bamlanivimab, bamlanivimab/etesevimab, or casirivimab/imdevimab. | ||
Sep 16 |
et al., Scientific Reports, doi:10.1038/s41598-022-19993-w | Reevaluation of antibody-dependent enhancement of infection in anti-SARS-CoV-2 therapeutic antibodies and mRNA-vaccine antisera using FcR- and ACE2-positive cells |
| In Vitro study showing that casirivimab/imdevimab may induce antibody-dependent enhancement (ADE) within a specific concentration range. No ADE was observed for sotrovimab. | ||
Sep 12 |
et al., American Journal of Obstetrics and Gynecology, doi:10.1016/j.ajog.2022.09.017 | Effectiveness of REGEN-COV combination monoclonal antibody infusion to reduce risk of COVID-19 hospitalization in pregnancy: A retrospective cohort study |
| 21% higher need for oxygen therapy [p=0.87], 1% higher severe cases [p=0.99], and 14% lower hospitalization [p=0.9]. Retrospective 764 pregnant patients with COVID-19 in the USA, 88 treated with casirivimab/imdevimab, showing no significant difference in outcomes. | ||
Sep 9 |
et al., Infection, doi:10.1007/s15010-022-01914-8 | Outcome of lung transplant recipients infected with SARS-CoV-2/Omicron/B.1.1.529: a Nationwide German study |
| 97% lower severe cases [p=0.45]. Retrospective 218 COVID+ lung transplant patients in Germany, showing no significant difference in severe cases with early casirivimab/imdevimab use. | ||
Jul 11 |
et al., Journal of Infection and Chemotherapy, doi:10.1016/j.jiac.2022.07.002 | Timing of REGEN-COV administration and progression to severe COVID-19 |
| Retrospective 342 patients in Japan, showing significantly greater efficacy of casirivimab/imdevimab with earlier treatment. The proportion of patients progressing to severe COVID-19 increased daily from symptom onset and increased sharpl.. | ||
Jun 4 |
et al., American Journal of Obstetrics & Gynecology MFM, doi:10.1016/j.ajogmf.2022.100673 | Outcomes of pregnant patients treated with REGEN-COV during the COVID-19 pandemic |
| 108% higher hospitalization [p=0.15]. Retrospective 86 pregnant COVID-19 patients, 36 treated with casirivimab/imdevimab, showing no significant difference in COVID-19 outcomes with treatment. | ||
May 26 |
et al., Journal of Infection and Chemotherapy, doi:10.1016/j.jiac.2022.05.012 | Clinical efficacy of casirivimab-imdevimab antibody combination treatment in patients with COVID-19 Delta variant |
| 46% lower need for oxygen therapy [p=0.004]. Retrospective 461 patients treated with casirivimab/imdevimab in Japan, and 461 matched controls, showing lower oxygen requirements with treatment. | ||
May 5 |
et al., Research Square, doi:10.21203/rs.3.rs-1170976/v1 (Preprint) | REGEN-COV antibody cocktail (casirivimab/imdevimab) for the treatment of inpatients with early hospital-acquired COVID-19: a single center experience |
| 92% lower mortality [p=0.03] and 94% lower need for oxygen therapy [p=0.02]. Retrospective 34 patients with hospital-acquired COVID-19, showing lower mortality and oxygen requirements with early casirivimab/imdevimab treatment. | ||
Mar 31 |
et al., Journal of the National Comprehensive Cancer Network, doi:10.6004/jnccn.2021.7309 | Real World Outcomes of Cancer Patients With SARS-CoV-2 Infection Receiving Monoclonal Antibodies |
| 82% lower hospitalization [p=0.004]. Retrospective 395 patients in the USA receiving casirivimab/imdevimab or bamlanivimab, showing lower risk of hospitalization with treatment, statistically significant for casirivimab/imdevimab. | ||
Feb 28 |
et al., medRxiv, doi:10.1101/2022.02.28.22270796 (Preprint) | Real-world Effectiveness of Casirivimab and Imdevimab in Patients With COVID-19 in the Ambulatory Setting: An Analysis of Two Large US National Claims Databases |
| 61% lower combined mortality/hospitalization [p<0.0001] and 61% lower hospitalization [p<0.0001]. Retrospective 4,396 casirivimab/imdevimab patients in the USA, showing lower combined mortality/hospitalization (CDM database) and lower hospitalization (PMTX+ database) with treatment. | ||
Feb 16 |
et al., bioRxiv, doi:10.1101/2022.02.15.480166 (Preprint) (In Vitro) | SARS-CoV-2 Omicron BA.2 Variant Evades Neutralization by Therapeutic Monoclonal Antibodies |
| In Vitro study showing that omicron BA.2 evades all monoclonal antibodies tested, including sotrovimab and tixagevimab/cilgavimab which retained activity for omicron BA.1. | ||
Feb 3 |
et al., Cureus, doi:10.7759/cureus.21882 | Clinical Prognosis of Patients With Mild COVID-19 Treated With Casirivimab/Imdevimab in Japan |
| 24% lower hospitalization [p=0.65]. Retrospective 104 outpatients in Japan, 30 treated with casirivimab/imdevimab, showing no significant difference in hospitalization. | ||
Jan 31 |
et al., medRxiv, doi:10.1101/2022.01.29.22270090 (Preprint) | Doubtful Clinical Benefit of Casirivimab-Imdevimab Treatment for Disease Severity Outcome of High-Risk Patients with SARS-CoV-2 Delta Variant Infection |
| 46% higher severe cases [p=0.26]. Retrospective 359 COVID+ patients in Israel, 116 treated with casirivimab/imdevimab, showing no significant difference with treatment in multivariable analysis. | ||
Jan 24 |
et al., bioRxiv, doi:10.1101/2022.01.23.477397 (Preprint) | Lack of Ronapreve (REGN-CoV; casirivimab and imdevimab) virological efficacy against the SARS-CoV 2 Omicron variant (B.1.1.529) in K18-hACE2 mice |
| K18-hACE2 mouse study showing that casirivimab/imdevimab was not effective for omicron at doses 2x higher than those effective for previous variants. | ||
Jan 14 |
et al., JAMA, doi:10.1001/jama.2021.24939768 | Effect of Subcutaneous Casirivimab and Imdevimab Antibody Combination vs Placebo on Development of Symptomatic COVID-19 in Early Asymptomatic SARS-CoV-2 Infection: A Randomized Clinical Trial |
| 85% lower hospitalization [p=0.25], 92% fewer combined hospitalization/ER visits [p=0.03], 33% fewer symptomatic cases [p=0.04], and 40% improved viral clearance [p=0.001]. RCT 204 asymptomatic COVID+ patients, 100 treated with subcutaneous casirivimab/imdevimab, showing lower development of symptoms, lower hospitalization, and faster viral clearance with treatment. Study conducted prior to widespread circul.. | ||
Dec 21 2021 |
et al., medRxiv, doi:10.1101/2021.12.19.21268078 (Preprint) | Real-world clinical outcomes of treatment with casirivimab-imdevimab among patients with mild-to-moderate coronavirus disease 2019 during the Delta variant pandemic |
| 45% lower progression [p=0.02]. Retrospective 949 patients in Japan, 314 treated with casirivimab/imdevimab showing significantly lower risk of deterioration with treatment. | ||
Dec 20 2021 |
et al., bioRxiv, doi:10.1101/2021.12.19.473354 (Preprint) (In Vitro) | Variable loss of antibody potency against SARS-CoV-2 B.1.1.529 (Omicron) |
| In Vitro study showing that omicron is substantially resistant to neutralization by monoclonal antibodies REGN10933, REGN10987, Ly-CoV016 and Ly-CoV555. S309 (the parent of Sotrovimab) had only 2-fold loss in potency. | ||
Dec 19 2021 |
et al., Journal of General and Family Medicine, doi:10.1002/jgf2.516 | The effect of casirivimab with imdevimab on disease progression in nonsevere COVID-19 patients in a single hospital in Japan |
| 92% lower ICU admission [p=0.04], 68% lower progression [p=0.006], and 29% shorter hospitalization [p=0.001]. Combined retrospective/prospective study in Japan with 53 casirivimab/imdevimab patients and 75 control patients, showing significantly lower progression with treatment. | ||
Dec 17 2021 |
et al., bioRxiv, doi:10.1101/2021.12.15.472828 (Preprint) (In Vitro) | An infectious SARS-CoV-2 B.1.1.529 Omicron virus escapes neutralization by several therapeutic monoclonal antibodies |
| In vitro study (Vero-TMPRSS2 and Vero-hACE2-TMPRSS2) showing complete loss of inhibitory activity for B.1.1.529 omicron with LY-CoV555, LY-CoV016, REGN10933, REGN10987, and CT-P59, ~12-fold decrease for COV2-2196/COV2-2130, and minimal ch.. | ||
Dec 15 2021 |
et al., bioRxiv, doi:10.1101/2021.12.14.472719 (Preprint) (In Vitro) | Striking Antibody Evasion Manifested by the Omicron Variant of SARS-CoV-2 |
| In Vitro study (Vero-E6-TMPRSS2) showing 18 of 19 monoclonal antibodies were no longer effective or significantly impaired with B.1.1.529 omicron. | ||
Dec 1 2021 |
et al., medRxiv, doi:10.1101/2021.11.30.21266756 (Preprint) | Association of subcutaneous or intravenous route of administration of casirivimab and imdevimab monoclonal antibodies with clinical outcomes in COVID-19 |
| 93% lower mortality [p=0.009], 56% lower combined mortality/hospitalization [p=0.0003], 48% lower hospitalization [p=0.005], and 40% fewer combined hospitalization/ER visits [p=0.003]. Prospective study comparing subcutaneous and intravenous casirivimab/imdevimab, and comparing to a PSM matched control set, showing significantly lower mortality and hospitalization with treatment. Controls were matched with EUA-eligible .. | ||
Nov 16 2021 |
et al., medRxiv, doi:10.1101/2021.11.10.21265889 (Preprint) | Repeat Subcutaneous Administration of REGEN-COV® in Adults is Well-Tolerated and Prevents the Occurrence of COVID-19 |
| 93% fewer symptomatic cases [p=0.002] and 93% fewer cases [p=0.002]. RCT 969 patients, 729 treated with monthly subcutaneous casirivimab/imdevimab, showing significantly lower risk of COVID-19 with treatment. There were no grade 3 injection site reactions or hypersensitivity reactions. Slightly more TEAEs .. | ||
Nov 8 2021 |
et al., The Journal of Infectious Diseases, doi:10.1093/infdis/jiac320 (date from earlier preprint) | Casirivimab and Imdevimab for the Treatment of Hospitalized Patients With COVID-19 |
| 36% lower mortality [p=0.02], 31% lower combined mortality/intubation [p=0.03], and 30% higher hospital discharge [p=0.02]. RCT 1,336 hospitalized patients with symptom onset <=10 days on low-flow or no supplemental oxygen, showing lower mortality with treatment. Cohorts 2&3 were paused mid-trial due to increased deaths in the treatment arm and these results w.. | ||
Nov 8 2021 |
Press Release (News) | New phase 3 analyses show that a single dose of REGEN-COV® (casirivimab and imdevimab) provides long-term protection against COVID-19 |
| 92% lower hospitalization [p=0.03], 81% fewer cases [p<0.0001], 89% fewer combined hospitalization/ER visits [p=0.06], and 81% fewer symptomatic cases [p<0.0001]. Long-term results for PEP RCT NCT04452318, with 841 baseline seronegative casirivimab/imdevimab patients and 842 placebo patients, showing significantly lower cases with treatment. | ||
Nov 4 2021 |
et al., International Journal of Infectious Diseases, doi:10.1016/j.ijid.2022.01.067 (date from earlier preprint) | Impact of Antibody Cocktail Therapy Combined with Casirivimab and Imdevimab on Clinical Outcome for Covid-19 patients in A Real-Life Setting: A Single Institute Analysis |
| 58% lower progression [p=0.05]. Retrospective 55 patients in Japan treated a median of 3 days from symptom onset with casirivimab/imdevimab, and 53 control patients, showing lower risk of further treatment including oxygen or antivirals. | ||
Nov 2 2021 |
et al., Research Square, doi:10.21203/rs.3.rs-995033/v1 (Preprint) (In Vitro) | Antibody escape and global spread of SARS-CoV-2 lineage A.27 |
| Anaysis of antibody escape showing variant A.27 completely escaped neutralization with LY-COV555 and partially with REGN10987. B.1.617.2 escaped these antibodies in a similar manner, suggesting that L452R facilitates the escape. Authors n.. | ||
Oct 20 2021 |
et al., The Journal of Infectious Diseases, doi:10.1093/infdis/jiab570 (date from earlier preprint) | Monoclonal Antibody Treatment of Breakthrough COVID-19 in Fully Vaccinated Individuals with High-Risk Comorbidities |
| 89% lower ICU admission [p=0.16], 85% lower need for oxygen therapy [p<0.0001], and 75% lower hospitalization [p<0.0001]. Retrospective 1,395 vaccinated COVID-19 cases, showing significantly lower hospitalization and oxygen supplementation with monoclonal antibody treatment, primarily casirivimab-imdevimab. Hospitalization was significantly associated with.. | ||
Oct 8 2021 |
et al., Open Forum Infectious Diseases, doi:10.1093/ofid/ofab512 | Real-world Assessment of 2,879 COVID-19 Patients Treated with Monoclonal Antibody Therapy: A Propensity Score-Matched Cohort Study |
| 77% lower mortality [p=0.18], 48% lower ICU admission [p=0.14], and 52% lower hospitalization [p<0.0001]. Retrospective 2,879 patients and matched controls in the USA, showing significantly lower mortality and hospitalization with bamlanivimab, bamlanivimab/etesevimab, and casirivimab/imdevimab. There was significantly lower hospitalization w.. | ||
Jun 23 2021 |
et al., Open Forum Infectious Diseases, doi:10.1093/ofid/ofab331 | Real-World Effectiveness and Tolerability of Monoclonal Antibody Therapy for Ambulatory Patients with Early COVID-19 |
| 91% lower hospitalization [p=0.0003]. Retrospective 115 patients treated with casirivimab/imdevimab showing lower mortality, hospital admission, and emergency department visits with treatment. Authors incorrectly state that "no other COVID-19 therapies for ambulatory pat.. | ||
Jun 16 2021 |
et al., The Lancet, doi:10.1016/S0140-6736(22)00163-5 (date from earlier preprint) | Casirivimab and imdevimab in patients admitted to hospital with COVID-19 (RECOVERY): a randomised, controlled, open-label, platform trial |
| 6% lower mortality [p=0.16] and 1% higher ventilation [p=0.88]. RCT 9,785 hospitalized patients in the UK showing lower mortality with casirivimab/imdevimab, with statistical significance reached for baseline seronegative patients. | ||
May 21 2021 |
et al., NEJM, doi:10.1056/NEJMoa2108163 (date from earlier preprint) | REGEN-COV Antibody Combination and Outcomes in Outpatients with Covid-19 |
| 71% lower combined mortality/hospitalization [p=0.001] and 29% faster recovery [p=0.001]. RCT 4,057 outpatients with >=1 risk factor for severe disease, showing significantly lower combined hospitalization/death, and significantly faster recovery with treatment. Median time from onset of symptoms 3 days. NCT04425629. | ||
Apr 12 2021 |
et al., NEJM, doi:10.1056/NEJMoa2109682 (press release 4/12/21) | Subcutaneous REGEN-COV Antibody Combination to Prevent Covid-19 |
| 89% fewer combined hospitalization/ER visits [p=0.06], 81% fewer symptomatic cases [p<0.0001], 62% faster recovery [p=0.0001], and 69% faster viral clearance [p=0.0001]. Prophylaxis trial reporting lower hospitalization/ER and symptomatic cases, and faster recovery with 1,200mg subcutaneous casirivimab with imdevimab. The same trial has updated results available in [c19regn.com]. NCT04452318. | ||
Mar 23 2021 |
Press Release (Preprint) | New phase III data shows investigational antibody cocktail casirivimab and imdevimab reduced hospitalisation or death by 70% in non-hospitalised patients with COVID-19 |
| 71% lower combined mortality/hospitalization [p<0.0001] and 29% faster recovery [p=0.0001]. Press release for new phase III data showing lower hospitalization/mortality, and faster symptom resolution among the subset of patients with at least one risk factor. Some variants may escape antibodies [cell.com]. | ||
Jan 26 2021 |
Press Release (Preprint) | Regeneron Reports Positive Interim Data with REGEN-COV™ Antibody Cocktail used as Passive Vaccine to Prevent COVID-19 |
| 94% fewer symptomatic cases [p=0.009] and 48% fewer cases [p=0.07]. Interim results of REGEN-COV prophylaxis showing 100% prevention of symptomatic infection (8/223 placebo vs. 0/186 REGEN-COV), and approximately 50% lower overall rates of infection (symptomatic and asymptomatic) (23/223 placebo vs. 10/18.. | ||
Sep 29 2020 |
Press Release (Preprint) | Regeneron's REGN-COV2 antibody cocktail reduced viral levels and improved symptoms in non-hospitalized COVID-19 patients |
| 38% faster recovery [p=0.22]. Analysis of the first 275 patients in a trial of the REGN-COV2 antibody cocktail showing reductions in viral load and the time to alleviate symptoms in non-hospitalized patients with COVID-19. Greatest improvements were seen with patients.. | ||
Aug 21 2020 |
et al., Science, 21 Aug 2020, 369:6506, 1014-1018, doi:10.1126/science.abd0831 (In Vitro) | Antibody cocktail to SARS-CoV-2 spike protein prevents rapid mutational escape seen with individual antibodies |
| In Vitro study showing that, under pressure from individual antibodies, mutant viruses were rapidly selected that evaded the blocking function of all individual antibodies tested, including antibodies that potently bind to highly-conserve.. | ||
Aug 21 2020 |
et al., Science, 21 Aug 2020, 369:6506, 1010-1014, doi:10.1126/science.abd0827 | Studies in humanized mice and convalescent humans yield a SARS-CoV-2 antibody cocktail |
| Study using humanized mice and blood samples from recovered COVID-19 patients to generate antibodies targeting multiple different regions of the critical receptor-binding domain (RBD) of the SARS-CoV-2 spike protein. The spike protein on .. | ||
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