ABSTRACT
Importance: The effectiveness of monoclonal antibodies (mAbs), casirivimab-imdevimab and sotrovimab, is unknown in patients with mild to moderate COVID-19 caused by the SARS-CoV-2 Delta variant. Objective: To evaluate the effectiveness of mAb against the Delta variant compared with no mAb treatment and to ascertain the comparative effectiveness of casirivimab-imdevimab and sotrovimab. Design, Setting, and Participants: This study comprised 2 parallel studies: (1) a propensity score-matched cohort study of mAb treatment vs no mAb treatment and (2) a randomized comparative effectiveness trial of casirivimab-imdevimab and sotrovimab. The cohort consisted of patients who received mAb treatment at the University of Pittsburgh Medical Center outpatient infusion centers and emergency departments from July 14 to September 29, 2021. Participants were patients with a positive SARS-CoV-2 test result who were eligible to receive mAbs according to emergency use authorization criteria. Exposure: For the trial, patients were randomized to either intravenous casirivimab-imdevimab or sotrovimab according to a system therapeutic interchange policy. Main Outcomes and Measures: For the cohort study, risk ratio (RR) estimates for the primary outcome of hospitalization or death by 28 days were compared between mAb treatment and no mAb treatment using propensity score-matched models. For the comparative effectiveness trial, the primary outcome was hospital-free days (days alive and free of hospitalization) within 28 days after mAb treatment, where patients who died were assigned -1 day in a bayesian cumulative logistic model adjusted for treatment location, age, sex, and time. Inferiority was defined as a 99% posterior probability of an odds ratio (OR) less than 1. Equivalence was defined as a 95% posterior probability that the OR was within a given bound. Results: A total of 3069 patients (1023 received mAb treatment: mean [SD] age, 53.2 [16.4] years; 569 women [56%]; 2046 had no mAb treatment: mean [SD] age, 52.8 [19.5] years; 1157 women [57%]) were included in the prospective cohort study, and 3558 patients (mean [SD] age, 54 [18] years; 1919 women [54%]) were included in the randomized comparative effectiveness trial. In propensity score-matched models, mAb treatment was associated with reduced risk of hospitalization or death (RR, 0.40; 95% CI, 0.28-0.57) compared with no treatment. Both casirivimab-imdevimab (RR, 0.31; 95% CI, 0.20-0.50) and sotrovimab (RR, 0.60; 95% CI, 0.37-1.00) were associated with reduced hospitalization or death compared with no mAb treatment. In the clinical trial, 2454 patients were randomized to receive casirivimab-imdevimab and 1104 patients were randomized to receive sotrovimab. The median (IQR) hospital-free days were 28 (28-28) for both mAb treatments, the 28-day mortality rate was less than 1% (n = 12) for casirivimab-imdevimab and less than 1% (n = 7) for sotrovimab, and the hospitalization rate by day 28 was 12% (n = 291) for casirivimab-imdevimab and 13% (n = 140) for sotrovimab. Compared with patients who received casirivimab-imdevimab, those who received sotrovimab had a median adjusted OR for hospital-free days of 0.88 (95% credible interval, 0.70-1.11). This OR yielded 86% probability of inferiority for sotrovimab vs casirivimab-imdevimab and 79% probability of equivalence. Conclusions and Relevance: In this propensity score-matched cohort study and randomized comparative effectiveness trial, the effectiveness of casirivimab-imdevimab and sotrovimab against the Delta variant was similar, although the prespecified criteria for statistical inferiority or equivalence were not met. Both mAb treatments were associated with a reduced risk of hospitalization or death in nonhospitalized patients with mild to moderate COVID-19 caused by the Delta variant. Trial Registration: ClinicalTrials.gov Identifier: NCT04790786.
Subject(s)
COVID-19 Drug Treatment , SARS-CoV-2 , Antibodies, Monoclonal, Humanized , Antibodies, Neutralizing , Bayes Theorem , Cohort Studies , Female , Humans , Middle Aged , Prospective StudiesABSTRACT
BACKGROUND: Monoclonal antibodies (mAb) that neutralize SARS-CoV-2 decrease hospitalization and death compared to placebo in patients with mild to moderate COVID-19; however, comparative effectiveness is unknown. We report the comparative effectiveness of bamlanivimab, bamlanivimab-etesevimab, and casirivimab-imdevimab. METHODS: A learning health system platform trial in a U.S. health system enrolled patients meeting mAb Emergency Use Authorization criteria. An electronic health record-embedded application linked local mAb inventory to patient encounters and provided random mAb allocation. Primary outcome was hospital-free days to day 28. Primary analysis was a Bayesian model adjusting for treatment location, age, sex, and time. Inferiority was defined as 99% posterior probability of an odds ratio < 1. Equivalence was defined as 95% posterior probability the odds ratio is within a given bound. FINDINGS: Between March 10 and June 25, 2021, 1935 patients received treatment. Median hospital-free days were 28 (IQR 28, 28) for each mAb. Mortality was 0.8% (1/128), 0.8% (7/885), and 0.7% (6/922) for bamlanivimab, bamlanivimab-etesevimab, and casirivimab-imdevimab, respectively. Relative to casirivimab-imdevimab (n = 922), median adjusted odds ratios were 0.58 (95% credible interval [CI] 0.30-1.16) and 0.94 (95% CI 0.72-1.24) for bamlanivimab (n = 128) and bamlanivimab-etesevimab (n = 885), respectively. These odds ratios yielded 91% and 94% probabilities of inferiority of bamlanivimab versus bamlanivimab-etesevimab and casirivimab-imdevimab, and an 86% probability of equivalence between bamlanivimab-etesevimab and casirivimab-imdevimab. INTERPRETATION: Among patients with mild to moderate COVID-19, bamlanivimab-etesevimab or casirivimab-imdevimab treatment resulted in 86% probability of equivalence. No treatment met prespecified criteria for statistical equivalence. Median hospital-free days to day 28 were 28 (IQR 28, 28) for each mAb. FUNDING AND REGISTRATION: This work received no external funding. The U.S. government provided the reported mAb. This trial is registered at ClinicalTrials.gov, NCT04790786.
Subject(s)
COVID-19 , Learning Health System , Antibodies, Monoclonal , Antibodies, Monoclonal, Humanized , Antibodies, Neutralizing , Bayes Theorem , Humans , SARS-CoV-2ABSTRACT
BACKGROUND: Physician non-compliance with clinical practice guidelines remains a critical barrier to high quality care. Serious games (using gaming technology for serious purposes) have emerged as a method of studying physician decision making. However, little is known about their validity. METHODS: We created a serious game and evaluated its construct validity. We used the decision context of trauma triage in the Emergency Department of non-trauma centers, given widely accepted guidelines that recommend the transfer of severely injured patients to trauma centers. We designed cases with the premise that the representativeness heuristic influences triage (i.e. physicians make transfer decisions based on archetypes of severely injured patients rather than guidelines). We randomized a convenience sample of emergency medicine physicians to a control or cognitive load arm, and compared performance (disposition decisions, number of orders entered, time spent per case). We hypothesized that cognitive load would increase the use of heuristics, increasing the transfer of representative cases and decreasing the transfer of non-representative cases. FINDINGS: We recruited 209 physicians, of whom 168 (79%) began and 142 (68%) completed the task. Physicians transferred 31% of severely injured patients during the game, consistent with rates of transfer for severely injured patients in practice. They entered the same average number of orders in both arms (control (C): 10.9 [SD 4.8] vs. cognitive load (CL):10.7 [SD 5.6], pâ=â0.74), despite spending less time per case in the control arm (C: 9.7 [SD 7.1] vs. CL: 11.7 [SD 6.7] minutes, p<0.01). Physicians were equally likely to transfer representative cases in the two arms (C: 45% vs. CL: 34%, pâ=â0.20), but were more likely to transfer non-representative cases in the control arm (C: 38% vs. CL: 26%, pâ=â0.03). CONCLUSIONS: We found that physicians made decisions consistent with actual practice, that we could manipulate cognitive load, and that load increased the use of heuristics, as predicted by cognitive theory.