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1.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-22274387

RESUMO

BackgroundCOVID-19 Convalescent Plasma (CCP) was an early and widely adopted putative therapy for severe COVID-19. Results from randomized control trials and observational studies have failed to demonstrate a clear therapeutic role for CCP for severe SARS-CoV-2 infection. Underlying these inconclusive findings is a broad heterogeneity in the concentrations of neutralizing antibodies (nAb) between different CCP donors. The present study was designed to evaluate nAb titer threshold for clinically effective CCP. MethodsWe conducted a double-blind, phase 2 study to evaluate the safety and effectiveness of nAb titer-defined CCP in adults admitted to an academic referral hospital. Patients positive on a SARS-CoV-2 nucleic acid amplification test and with symptoms for < 10 days were eligible. Participants received either CCP with nAb titers [≥]1:160-1:640 (standard titer group) or >1:640 (high titer group) in addition to standard of care treatments. Adverse events were contrasted by CCP titer. The primary clinical outcome was time to hospital discharge, with mortality and respiratory support evaluated as secondary outcomes. FindingsBetween August 28 and December 4, 2020, 316 participants were screened, 55 received CCP, with 41 and 14 receiving standard versus high titer CCP, respectively. Participants were a median of 61 years of age (IQR 52-67), 36% women, 25% Black and 33% Hispanic. Severe adverse events (SAE) ([≥] grade 3) occurred in 4 (29%) and 23 (56%) of participants in the high versus standard titer groups, respectively by day 28 (Risk Difference -0.28 [95% CI -0.56, 0.01]). There were no observed treatment-related AEs. By day 55, time to hospital discharge was shorter among participants receiving high versus standard titer, accounting for death as a competing event (hazard ratio 1.94 [95% CI 1.05, 3.58], Grays p=0.02). InterpretationIn this phase 2 trial in a high-risk population of patients admitted for Covid-19, we found earlier time to hospital discharge and lower occurrences of life-threatening SAEs among participants receiving CCP with nAb titers >1:640 compared with participants receiving CCP with lower nAb titer CCP. Though limited by a small study size these findings support further study of high-nAb titer CCP defined as >1:640 in the treatment of COVID-19. FundingThis clinical study was supported by the UNC Health Foundation and the North Carolina Policy Collaboratory at the University of North Carolina at Chapel Hill with funding from the North Carolina Coronavirus Relief Fund established and appropriated by the North Carolina General Assembly. The laboratory assays for neutralizing antibody titers and SARS-CoV-2 specific antibody-binding assays were partially supported by The NIH NCI/NIAID SeroNet Serocenter of Excellence Award U54 CA260543. Research in ContextO_ST_ABSEvidence before this studyC_ST_ABSCOVID-19 Convalescent Plasma (CCP) has emergency use authorization from the FDA for early treatment of COVID-19 in either outpatient or inpatient settings. Evidence supporting the use of CCP for severe COVID-19 is mixed and still emerging. One major limitation in interpreting published clinical trials and the clinical role of CCP is incomplete understanding of necessary neutralizing antibody (nAb) titer for clinically effective CCP. Observational studies suggest that higher antibody-content CCP is more effective than lower antibody-content CCP, or that very low antibody-content CCP is harmful. We searched PubMed articles published between February 1, 2020, and April 15, 2022, using the terms "COVID-19", "convalescent plasma", "SARS-CoV-2", and "CCP" alone and in combination. Our search yielded 6,468 results which we filtered to 280 and 162 by selecting Clinical Trial and Randomized Controlled Trial article types, respectively. Among these, we identified 25 open-label or blinded efficacy or effectiveness studies in hospitalized patients that were relevant to our study. Preliminary reports show wide variability in the antibody content of CCP used in clinical trials, the assays used to define CCP antibody content, and the estimates of clinical outcomes following CCP therapy for hospitalized patients. Only one study deliberately infused CCP with nAb > 1:640. Post-hoc analyses of potent monoclonal antibody therapy in hospitalized patients in the UK showed survival benefit when monoclonal antibody was infused to patients who had not yet seroconverted by spike antibody ELISA, suggesting that if dosed appropriately, antibody-based therapies may have a role in improving outcomes of severe COVID-19. Added value of this studyThis phase 2 study showed that CCP with high nAb titer (>1:640) provided more rapid recovery to hospital discharge and fewer COVID-19 attributable AEs than CCP with nAb titer between the FDA-recommended minimum standard and 4-fold higher ([≥]1:160-1:640). The hazard ratio of time to hospital discharge from baseline through day 55, accounting for death as a competing event, contrasting patients receiving high versus standard CCP titer was 1.94 (95% CI 1.05-3.58). Adjusted hazard ratios of high versus standard titer CCP receipt for time to hospital discharge were consistent with the primary unadjusted findings. Mortality through 55 days was lower in the high titer group, but with a wide confidence interval that did not reach statistical significance. Implications of all available evidenceOur data that CCP with nAb >1:640 expedites recovery of patients admitted with COVID-19 compared with CCP with nAb [≥]1:160-1:640 suggests that a threshhold of nAb [≥]1:160 may be too low to define CCP as high titer. Analyses in larger CCP trials should consider full reporting of nAb in CCP units administered at individual study participant level, and specifically whether CCP contained nAb >1:640. Further investigation of CCP with nAb >1:640 is warranted given that raising the threshhold of nAb, or a correlative specific anti-spike antibody assay, used to qualify high titer CCP in clinical trials could inform policy guidance and clinical use of CCP.

2.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-22273913

RESUMO

ImportanceUnderstanding the severity of post-vaccination COVID-19 breakthrough illness among people with HIV (PWH) can inform vaccine guidelines and risk-reduction recommendations. ObjectiveEstimate the rate and risk of severe breakthrough illness among vaccinated PWH and people without HIV (PWoH) who experience a breakthrough infection. Design, setting, and participantsThe Corona-Infectious-Virus Epidemiology Team (CIVET-II) collaboration consists of four US longitudinal cohorts from integrated health systems and academic centers. Adults ([≥]18 years old), in-care, fully vaccinated by June 30, 2021 with HIV, and matched PWoH (on date fully vaccinated, age group, race/ethnicity, and sex) were the source population. Those who experienced a post-vaccination SARS-CoV-2 breakthrough infection were eligible. Severe COVID-19 breakthrough illness was defined as hospitalization due to COVID-19. Discrete time proportional hazards models estimated adjusted hazard ratios (aHR) and 95% confidence intervals ([,]) of severe breakthrough illness by HIV status adjusting for demographics, COVID-19 vaccine type, and clinical factors. The proportion of patients requiring mechanical ventilation or died was compared by HIV status. ExposureHIV infection OutcomeSevere COVID-19 breakthrough illness, defined as hospitalization within 28 days after a breakthrough SARS-CoV-2 infection with a primary or secondary COVID-19 discharge diagnosis. ResultsAmong 1,241 PWH and 2,408 PWoH with breakthrough infections, the cumulative incidence of severe illness in the first 28 days was low and comparable between PWoH and PWH (7.3% vs. 6.7%, respectively, risk difference=-0.67% [-2.58%, 1.23%]). The risk of severe breakthrough illness was 59% higher in PWH with CD4 counts <350 cells/mm3 compared with PWoH (aHR=1.59 [0.99, 2.46]). In multivariable analyses among PWH, being female, older, having a cancer diagnosis, and lower CD4 count increased the risk of severe breakthrough illness, while previous COVID-19 reduced the risk. Among all patients, 10% were mechanically ventilated and 8% died, with no difference by HIV status. Conclusions and RelevanceThe risk of severe COVID-19 breakthrough illness within 28 days of a breakthrough infection was low among vaccinated PWH and PWoH. However, PWH with moderate and severe immune suppression had a higher risk of severe breakthrough infection. Recommendations for additional vaccine doses and risk-reduction strategies for PWH with moderate immune suppression may be warranted. Key PointsO_ST_ABSQuestionC_ST_ABSIn 2021, among fully vaccinated people with COVID-19 breakthrough illness, was the risk of severe illness higher in people with HIV (PWH) compared to people without HIV (PWoH)? FindingsPWH with <350 cells/mm3 have a 59% increased risk of severe breakthrough illness compared to PWoH. MeaningVaccinations effectively reduce the risk of severe COVID-19 infection in both PWH and PWoH; however, PWH having a CD4 count <350 cells/mm3 are at higher risk of severe breakthrough infection compared to PWoH. PWH with moderate immune suppression should be considered for additional vaccine dosages and other risk-reduction measures.

3.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-21267296

RESUMO

ObjectivesTo define the incidence of clinically-detected COVID-19 in people with HIV (PWH) in the US and evaluate how racial and ethnic disparities, comorbidities, and HIV-related factors contribute to risk of COVID-19. DesignObservational study within the CFAR Network of Integrated Clinical Systems cohort in 7 cities during 2020. MethodsWe calculated cumulative incidence rates of COVID-19 diagnosis among PWH in routine care by key characteristics including race/ethnicity, current and lowest CD4 count, and geographic area. We evaluated risk factors for COVID-19 among PWH using relative risk regression models adjusted with disease risk scores. ResultsAmong 16,056 PWH in care, of whom 44.5% were Black, 12.5% were Hispanic, with a median age of 52 years (IQR 40-59), 18% had a current CD4 count < 350, including 7% < 200; 95.5% were on antiretroviral therapy, and 85.6% were virologically suppressed. Overall in 2020, 649 PWH were diagnosed with COVID-19 for a rate of 4.94 cases per 100 person-years. The cumulative incidence of COVID-19 was 2.4-fold and 1.7-fold higher in Hispanic and Black PWH respectively, than non-Hispanic White PWH. In adjusted analyses, factors associated with COVID-19 included female sex, Hispanic or Black identity, lowest historical CD4 count <350 (proxy for CD4 nadir), current low CD4/CD8 ratio, diabetes, and obesity. ConclusionsOur results suggest that the presence of structural racial inequities above and beyond medical comorbidities increased the risk of COVID-19 among PWH PWH with immune exhaustion as evidenced by lowest historical CD4 or current low CD4:CD8 ratio had greater risk of COVID-19.

4.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-21267182

RESUMO

ImportanceRecommendations for additional doses of COVID vaccine are restricted to people with HIV who have advanced disease or unsuppressed HIV viral load. Understanding SARS-CoV-2 infection risk post-vaccination among PWH is essential for informing vaccination guidelines. ObjectiveEstimate the risk of breakthrough infections among fully vaccinated people with (PWH) and without (PWoH) HIV in the US. Design, setting, and participantsThe Corona-Infectious-Virus Epidemiology Team (CIVET)-II cohort collaboration consists of 4 longitudinal cohorts from integrated health systems and academic health centers. Each cohort identified individuals [≥]18 years old, in-care, and fully vaccinated for COVID-19 through 30 June 2021. PWH were matched to PWoH on date fully vaccinated, age group, race/ethnicity, and sex at birth. Incidence rates per 1,000 person-years and cumulative incidence of breakthrough infections with 95% confidence intervals ([,]) were estimated by HIV status. Cox proportional hazards models estimated adjusted hazard ratios (aHR) of breakthrough infections by HIV status adjusting for demographic factors, prior COVID-19 illness, vaccine type (BNT162b2, [Pfizer], mRNA-1273 [Moderna], Jansen Ad26.COV2.S [J&J]), calendar time, and cohort. Risk factors for breakthroughs among PWH, were also investigated. ExposureHIV infection OutcomeCOVID-19 breakthrough infections, defined as laboratory evidence of SARS-CoV-2 infection or COVID-19 diagnosis after an individual was fully vaccinated. ResultsAmong 109,599 individuals (31,840 PWH and 77,759 PWoH), the rate of breakthrough infections was higher in PWH versus PWoH: 44 [41, 48] vs. 31 [29, 33] per 1,000 person-years. Cumulative incidence at 210 days after date fully vaccinated was low, albeit higher in PWH versus PWoH overall (2.8% versus 2.1%, log-rank p<0.001, risk difference=0.7% [0.4%, 1.0%]) and within each vaccine type. Breakthrough infection risk was 41% higher in PWH versus PWoH (aHR=1.41 [1.28, 1.56]). Among PWH, younger age (18-24 versus 45-54), history of COVID-19 prior to fully vaccinated date, and J&J vaccination (versus Pfizer) were associated with increased risk of breakthroughs. There was no association of breakthrough with HIV viral load suppression or CD4 count among PWH. Conclusions and RelevanceCOVID-19 vaccination is effective against infection with SARS-CoV-2 strains circulating through 30 Sept 2021. PWH have an increased risk of breakthrough infections compared to PWoH. Recommendations for additional vaccine doses should be expanded to all PWH.

5.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-21265063

RESUMO

BackgroundUnderstanding the spectrum of SARS-CoV-2 infection and COVID-19 disease in people with HIV (PWH) is critical to provide clinical guidance and implement risk-reduction strategies. ObjectiveTo characterize COVID-19 in PWH in the United States and identify predictors of disease severity. DesignObservational cohort study. SettingGeographically diverse clinical sites in the CFAR Network of Integrated Clinical Systems (CNICS) ParticipantsAdults receiving HIV care through December 31, 2020. MeasurementsCOVID-19 cases and severity (hospitalization, intensive care, death). ResultsOf 16,056 PWH in care, 649 were diagnosed with COVID-19 between March-December 2020. Case fatality was 2%; 106 (16.3%) were hospitalized and 12 died. PWH with current CD4 count <350 cells/mm3 (aRR 2.68; 95%CI 1.93-3.71; P<.001) or lowest recorded CD4 count <200 (aRR 1.67; 95%CI 1.18-2.36; P<.005) had greater risk of hospitalization. HIV viral load suppression and antiretroviral therapy (ART) status were not associated with hospitalization, although the majority of PWH were suppressed (86%). Black PWH were 51% more likely to be hospitalized with COVID-19 compared to other racial/ethnic groups (aRR 1.51; 95%CI 1.04-2.19, P=.03). Chronic kidney disease (CKD), chronic obstructive pulmonary disease, diabetes, hypertension, obesity, and increased cardiovascular and hepatic fibrosis risk scores were associated with higher risk of hospitalization. PWH who were older, not on ART, with current CD4 <350, diabetes, and CKD were overrepresented amongst PWH who required intubation or died. LimitationsUnable to compare directly to persons without HIV; underestimate of total COVID-19 cases. ConclusionsPWH with CD4 <350 cells/mm3, low CD4/CD8 ratio, and history of CD4 <200, have a clear excess risk of severe COVID-19, after accounting for comorbidities also associated with severe outcomes. PWH with these risk factors should be prioritized for COVID-19 vaccination, early treatment, and monitored closely for worsening illness.

6.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-21250493

RESUMO

The coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome-related coronavirus-2 (SARS-CoV-2) has now caused over 2 million deaths worldwide and continues to expand. Currently, much is unknown about functionally neutralizing human antibody responses and durability to SARS-CoV-2. Using convalescent sera collected from 101 COVID-19 recovered individuals 21-212 days after symptom onset with forty-eight additional longitudinal samples, we measured functionality and durability of serum antibodies. We also evaluated associations between individual demographic and clinical parameters with functional neutralizing antibody responses to COVID-19. We found robust antibody durability out to six months, as well as significant positive associations with the magnitude of the neutralizing antibody response and male sex. We also show that SARS-CoV-2 convalescent neutralizing antibodies are higher in individuals with cardio-metabolic comorbidities. SignificanceIn this study we found that neutralizing antibody responses in COVID-19 convalescent individuals vary in magnitude but are durable and correlate well with RBD Ig binding antibody levels compared to other SARS-CoV-2 antigen responses. In our cohort, higher neutralizing antibody titers are independently and significantly associated with male sex compared to female sex. We also show for the first time, that higher convalescent antibody titers in male donors are associated with increased age and symptom grade. Furthermore, cardio-metabolic co-morbidities are associated with higher antibody titers independently of sex. Here, we present an in-depth evaluation of serologic, demographic, and clinical correlates of functional antibody responses and durability to SARS-CoV-2.

7.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-20100404

RESUMO

We describe early outcomes in 11 COVID-19 patients treated with the IL-6 receptor inhibitor tocilizumab. While C-reactive protein decreased, neither clinical improvement nor reduced temperature or oxygen requirements was observed in most patients. Our findings contrast with prior reports and raise questions about tocilizumab use in severe COVID-19.

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