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Early Convalescent Plasma for High-Risk Outpatients with Covid-19
Frederick K Korley1, Valerie Durkalski-Mauldin1, Sharon D Yeatts1
1From the University of Michigan, Ann Arbor (F.K.K., R.D.D., C.V.H., V.L.W.S., C.F.G., N.L.H., R.S., W.B.), Spectrum Health, Grand Rapids (J.C.R.), and Michigan State University, East Lansing (J.C.R.) - all in Michigan; the Medical University of South Carolina, Charleston (V.D.-M., S.D.Y., L.D.F., E.L.); Stanford University, Palo Alto, CA (K.S., J.M.H., S.J., J.Q.); Vitalant Research Institute, Scottsdale, AZ (L.J.D.); the National Heart, Lung, and Blood Institute, Bethesda, MD (N.E.K.); the University of Pittsburgh, Pittsburgh (A.K., J.F.M., D.J.T., C.W.C.); Harbor-UCLA Medical Center, Los Angeles (K.Y.); Cooper University Hospital, Camden, NJ (C.W.J.); Oregon Health and Science University, Portland (B.K.); Health Partners Methodist Hospital, St. Louis Park, MN (A.B.); and the University of Chicago, Chicago (D.G.B.).
Insights
Early convalescent plasma treatment for high-risk COVID-19 patients did not prevent disease progression. This randomized trial found no significant difference in outcomes between patients receiving high-titer antibody plasma and those receiving a placebo.
Area of Science:
- Immunology
- Infectious Diseases
- Clinical Trials
Background:
- Early administration of convalescent plasma (CP) from recovered coronavirus disease 2019 (COVID-19) donors was investigated for its potential to prevent disease progression in high-risk patients.
- Patients with COVID-19 symptoms were targeted for intervention within 7 days of symptom onset.
Purpose of the Study:
- To evaluate the efficacy of high-titer COVID-19 convalescent plasma in preventing disease progression in high-risk outpatients.
- To assess the impact of convalescent plasma on disease severity, hospitalization rates, and mortality.
Main Methods:
- A randomized, multicenter, single-blind trial involving 511 high-risk COVID-19 patients (age ≥50 or with risk factors) treated in the emergency department.
- Participants received either one unit of high-titer SARS-CoV-2 antibody convalescent plasma or a placebo.
- The primary outcome was disease progression within 15 days, defined as hospitalization, urgent care visit, or death without hospitalization.
Main Results:
- Disease progression occurred in 30.0% of the convalescent plasma group and 31.9% of the placebo group (risk difference, 1.9 percentage points).
- No significant differences were observed in the primary outcome, worst illness severity, or hospital-free days between the groups.
- Five deaths occurred in the plasma group and one in the placebo group.
Conclusions:
- Administration of COVID-19 convalescent plasma to high-risk outpatients within one week of symptom onset did not prevent disease progression.
- The findings suggest that this intervention strategy may not be effective for preventing adverse outcomes in this patient population.
Background:
Early administration of convalescent plasma obtained from blood donors who have recovered from coronavirus disease 2019 (Covid-19) may prevent disease progression in acutely ill, high-risk patients with Covid-19.
Methods:
In this randomized, multicenter, single-blind trial, we assigned patients who were being treated in an emergency department for Covid-19 symptoms to receive either one unit of convalescent plasma with a high titer of antibodies against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) or placebo. All the patients were either 50 years of age or older or had one or more risk factors for disease progression. In addition, all the patients presented to the emergency department within 7 days after symptom onset and were in stable condition for outpatient management. The primary outcome was disease progression within 15 days after randomization, which was a composite of hospital admission for any reason, seeking emergency or urgent care, or death without hospitalization. Secondary outcomes included the worst severity of illness on an 8-category ordinal scale, hospital-free days within 30 days after randomization, and death from any cause.
Results:
A total of 511 patients were enrolled in the trial (257 in the convalescent-plasma group and 254 in the placebo group). The median age of the patients was 54 years; the median symptom duration was 4 days. In the donor plasma samples, the median titer of SARS-CoV-2 neutralizing antibodies was 1:641. Disease progression occurred in 77 patients (30.0%) in the convalescent-plasma group and in 81 patients (31.9%) in the placebo group (risk difference, 1.9 percentage points; 95% credible interval, -6.0 to 9.8; posterior probability of superiority of convalescent plasma, 0.68). Five patients in the plasma group and 1 patient in the placebo group died. Outcomes regarding worst illness severity and hospital-free days were similar in the two groups.
Conclusions:
The administration of Covid-19 convalescent plasma to high-risk outpatients within 1 week after the onset of symptoms of Covid-19 did not prevent disease progression. (SIREN-C3PO ClinicalTrials.gov number, NCT04355767.).
