Association of subcutaneous or intravenous route of administration of casirivimab and imdevimab monoclonal antibodies with clinical outcomes in COVID-19
McCreary et al.,
Association of subcutaneous or intravenous route of administration of casirivimab and imdevimab monoclonal..,
medRxiv, doi:10.1101/2021.11.30.21266756 (Preprint)
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 risk factors only, authors were unable to determine symptom severity.
Efficacy is variant dependent. In Vitro research suggests a lack of efficacy for omicron [Liu, Sheward, Tatham, VanBlargan].
risk of death, 93.0% lower, RR 0.07, p = 0.009, treatment 1 of 652 (0.2%), control 29 of 1,304 (2.2%), NNT 48, propensity score matching.
|
risk of death/hospitalization, 56.0% lower, RR 0.44, p < 0.001, treatment 22 of 652 (3.4%), control 101 of 1,304 (7.7%), NNT 23, propensity score matching, primary outcome.
|
risk of hospitalization, 48.0% lower, RR 0.52, p = 0.005, treatment 22 of 652 (3.4%), control 85 of 1,304 (6.5%), NNT 32, propensity score matching.
|
risk of hospitalization/ER, 40.0% lower, RR 0.60, p = 0.003, treatment 40 of 652 (6.1%), control 133 of 1,304 (10.2%), NNT 25, propensity score matching.
|
SQ vs. IV death, 53.0% lower, RR 0.47, p = 0.52, treatment 1 of 969 (0.1%), control 3 of 1,216 (0.2%), NNT 697, adjusted per study.
|
SQ vs. IV death/hosp., 71.0% higher, RR 1.71, p = 0.06, treatment 27 of 969 (2.8%), control 21 of 1,216 (1.7%), adjusted per study.
|
SQ vs. IV hospitalization, 79.0% higher, RR 1.79, p = 0.046, treatment 27 of 969 (2.8%), control 20 of 1,216 (1.6%), adjusted per study.
|
SQ vs. IV ER/hosp., 15.0% lower, RR 0.85, p = 0.38, treatment 47 of 969 (4.9%), control 71 of 1,216 (5.8%), NNT 101, adjusted per study.
|
Effect extraction follows pre-specified rules prioritizing more serious outcomes. Submit updates
|

McCreary et al., 1 Dec 2021, prospective, USA, preprint, 27 authors, study period 14 July, 2021 - 26 October, 2021, average treatment delay 6.0 days.
Abstract: medRxiv preprint doi: https://doi.org/10.1101/2021.11.30.21266756; this version posted December 1, 2021. The copyright holder for this preprint
(which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity.
It is made available under a CC-BY-NC-ND 4.0 International license .
Association of subcutaneous or intravenous route of administration of casirivimab and
imdevimab monoclonal antibodies with clinical outcomes in COVID-19
Authors: Erin K. McCreary PharmD1*, J. Ryan Bariola MD1, Richard J. Wadas MD2, Judith A. Shovel
BSN3, Mary Kay Wisniewski MA3, Michelle Adam RN2, Debbie Albin BS4, Tami Minnier MS3, Mark
Schmidhofer MD5, Russell Meyers MBA2, Oscar C. Marroquin MD6, Kevin Collins MBA6, William
Garrard PhD6, Lindsay R. Berry PhD7, Scott Berry PhD7, Amy M. Crawford PhD7, Anna McGlothlin
PhD7, Kelsey Linstrum MS8, Anna Nakayama MS8, Stephanie K. Montgomery MS8, Graham M. Snyder
MD MS1, Donald M. Yealy MD2, Derek C. Angus MD MPH8,10, Paula L. Kip PhD8, Christopher W.
Seymour MD MSc8-10, David T. Huang MD MPH2,8-10, Kevin E. Kip PhD6
1. Division of Infectious Diseases, Department of Medicine, University of Pittsburgh School of
Medicine, Pittsburgh, PA, USA
2. Department of Emergency Medicine, University of Pittsburgh School of Medicine,
Pittsburgh, PA, USA
3. Wolff Center, UPMC, Pittsburgh, PA, USA
4. Supply Chain Management/HC Pharmacy, UPMC, Pittsburgh, PA, USA
5. Division of Cardiology, Department of Medicine, University of Pittsburgh School of
Medicine, Pittsburgh, PA, USA
6. Clinical Analytics, UPMC, Pittsburgh, PA, USA
7. Berry Consultants, Austin, TX, USA
8. Office of Healthcare Innovation, UPMC, Pittsburgh, PA, USA
9. Clinical Research Investigation and Systems Modeling of Acute Illness (CRISMA) Center,
Department of Critical Care Medicine, University of Pittsburgh School of Medicine,
Pittsburgh, PA, USA
10. Department of Critical Care Medicine, University of Pittsburgh School of Medicine,
Pittsburgh, PA, USA
*Corresponding Author:
Erin K. McCreary, PharmD, BCPS, BCIDP
Clinical Assistant Professor of Medicine, University of Pittsburgh
Director of Stewardship Innovation, UPMC and Infectious Disease Connect
Falk Medical Building, Suite 5B
3601 Fifth Avenue
Pittsburgh, PA 15213
C: 484-515-9589
E: mccrearye3@upmc.edu
Funding: This work did not receive external funding. The U.S. federal government provided the
monoclonal antibody treatment reported in this manuscript.
Abstract word count: 347
Manuscript word count: 2,996
Tables: 4
Figures: 1
Conflict of Interest: None of the authors received any payments or influence from a third-party source
for the work presented.
1
NOTE: This preprint reports new research that has not been certified by peer review and should not be used to guide clinical practice.
medRxiv preprint doi: https://doi.org/10.1101/2021.11.30.21266756; this version posted December 1, 2021. The copyright holder for this preprint
(which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity.
It is made available under a CC-BY-NC-ND 4.0 International license .
Key Points
Question: Among outpatients with mild to moderate COVID-19, is subcutaneously administered
casirivimab and imdevimab associated with improved risk-adjusted 28-day clinical outcomes
compared to non-treatment with monoclonal antibodies, and clinically similar association
compared to intravenously administered..
Late treatment
is less effective
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.
Submit