Distribution of age, sex, race, and ethnicity in COVID-19 clinical drug trials in the United States: A review

BACKGROUND

COVID-19 quickly overwhelmed the world, but disproportionately affects certain communities, particularly minority groups. Despite overrepresentation among COVID-19 cases and death, minority groups were underrepresented in some of the early COVID-19 clinical trials.

OBJECTIVE

To assess and compare the demographic characteristics of COVID-19 clinical trial participants to national COVID-19 data.

METHODS

PubMed was searched from December 1, 2019 to November 24, 2020, for randomized controlled trials evaluating a pharmacologic treatment for COVID-19 patients from one or more U.S. sites written in the English language following the PRISMA checklist. Descriptive statistics were calculated to characterize patient demographics enrolled in the included clinical trials, as well as for comparison with national COVID-19 data.

RESULTS

A total of 4472 records were identified, of which 16 studies were included. The median number of participants was higher in studies of nonhospitalized patients compared to those of hospitalized patients (n = 452 [range 20-1062] vs n = 243 [152-2795]). Ten (63%) studies reported mean or median ages of 50 years or older among all study arms. Males comprised more than half of the study cohort in ten (63%) studies. Race and ethnicity were reported separately in four (25%) studies but were combined when reported in five (31%) studies, while six (38%) reported only race or ethnicity. Proportional representation based on age, sex, race, and ethnicity was evident in some trials, but not in others, when compared to national data.

CONCLUSION

Overall, participants often did not reflect the actual population with COVID-19 and demographic characteristics were inconsistently reported.

The effect of waning on antibody levels and memory B cell recall following SARS-CoV-2 infection or vaccination

As of March 2022, there have been over 450 million reported SARS-CoV-2 cases worldwide, and more than 4 billion people have received their primary series of a COVID-19 vaccine. In order to longitudinally track SARS-CoV-2 antibody levels in people after vaccination or infection, a large-scale COVID-19 sero-surveillance progam entitled SPARTA (SeroPrevalence and Respiratory Tract Assessment) was established early in the pandemic. Anti-RBD antibody levels were tracked in more than 1,000 people. There was no significant decrease in antibody levels during the first 14 months after infection in unvaccinated participants, however, significant waning of antibody levels was observed following vaccination, regardless of previous infection status. Moreover, participants who were pre-immune to SARS-CoV-2 prior to vaccination seroconverted to significantly higher antibody levels, and antibodies were maintained at significantly higher levels than in previously infected, unvaccinated participants. This pattern was entirely due to differences in the magnitude of the initial seroconversion event, and the rate of antibody waning was not significantly different based on the pre-immune status. Participants who received a third (booster) dose of an mRNA vaccine not only increased their anti-RBD antibody levels ~14-fold, but they also had ~3 times more anti-RBD antibodies compared to the peak of their antibody levels after receiving their primary vaccine series. In order to ascertain whether the presence of serum antibodies is important for long-term seroprotection, PBMCs from 13 participants who lost all detectable circulating antibodies after vaccination or infection were differentiated into memory cells in vitro. There was a significant recall of memory B cells in the absence of serum antibodies in 70% of the vaccinated participants, but not in any of the infected participants. Therefore, there is a strong connection between anti-RBD antibody levels and the effectiveness of memory B cell recall.

460. Disproportionalities in COVID-19 Clinical Drug Trials in the United States: A Systematic Literature Review

Background

To combat higher rates of COVID-19 infection, hospitalization, and death among minorities, it is crucial to identify safe, efficacious, and generalizable treatments. Therefore, the purpose of this systematic literature review was to assess the demographic characteristics of COVID-19 clinical trial participants.

Methods

A literature search was performed according to the PRISMA checklist using PubMed from December 1, 2019 to November 24, 2020 with the following search terms: 2019-nCoV, COVID-19, SARS-CoV-2, clinical trial, randomized controlled trial, observational study, and veterinary. To capture additional results, keyword searches were performed using various versions and plural endings with the title/abstract field tag. Randomized controlled trials evaluating a pharmacologic treatment for COVID-19 patients from one or more U.S site written in the English language were eligible for inclusion. Descriptive statistics were calculated to characterize age, gender, race, and ethnicity of patients enrolled in the included COVID-19 clinical trials, as well as for comparison with national COVID-19 data.

Results

A total of 4472 records were identified, of which 16 were included. Most were placebo-controlled (69%) and included hospitalized patients with COVID-19 (69%). Demographic data were reported for each study arm in 81% of studies. Median number of participants was higher in studies of nonhospitalized patients (n=452 [range 20-1062] vs n=243 [range 152-2795]). Nine (56%) studies reported mean or median ages of 50 years or older amongst all study arms. Males comprised more than half of the study cohort in 50% of studies. Race and ethnicity were reported separately in five (31%) studies, reported in combination in four (25%), while six (38%) reported only race or ethnicity. White or Caucasian patients made up most participants across all arms in 75% of studies. Based on national COVID-19 data, hospitalizations were similar between White persons and African American persons, but higher than other race or ethnic groups, and evenly distributed among males and females.

Conclusion

Lack of heterogeneously reporting demographic characteristics of COVID-19 clinical trial participants limits the ability to assess the generalizability of pharmacologic treatments for COVID-19.

Disclosures

All Authors: No reported disclosures

SARS-CoV-2 mRNA Vaccines Elicit Different Responses in Immunologically Naïve and Pre-Immune Humans

As the COVID-19 pandemic continues, the authorization of vaccines for emergency use has been crucial in slowing down the rate of infection and transmission of the SARS-CoV-2 virus that causes COVID-19. In order to investigate the longitudinal serological responses to SARS-CoV-2 natural infection and vaccination, a large-scale, multi-year serosurveillance program entitled SPARTA (SARS SeroPrevalence and Respiratory Tract Assessment) was initiated at 4 locations in the U.S. The serological assay presented here measuring IgG binding to the SARS-CoV-2 receptor binding domain (RBD) detected antibodies elicited by SARS-CoV-2 infection or vaccination with a 95.5% sensitivity and a 95.9% specificity. We used this assay to screen more than 3100 participants and selected 20 previously infected pre-immune and 32 immunologically naïve participants to analyze their antibody binding to RBD and viral neutralization (VN) responses following vaccination with two doses of either the Pfizer-BioNTech BNT162b2 or the Moderna mRNA-1273 vaccine. Vaccination not only elicited a more robust immune reaction than natural infection, but the level of neutralizing and anti-RBD antibody binding after vaccination is also significantly higher in pre-immune participants compared to immunologically naïve participants (p<0.0033). Furthermore, the administration of the second vaccination did not further increase the neutralizing or binding antibody levels in pre-immune participants (p=0.69). However, ~46% of the immunologically naïve participants required both vaccinations to seroconvert.

Functional characterization of SARS-CoV-2 vaccine elicited antibodies in immunologically naïve and pre-immune humans

As the COVID-19 pandemic continues, the authorization of vaccines for emergency use has been crucial in slowing down the rate of infection and transmission of the SARS-CoV-2 virus that causes COVID-19. In order to investigate the longitudinal serological responses to SARS-CoV-2 natural infection and vaccination, a large-scale, multi-year serosurveillance program entitled SPARTA (SARS SeroPrevalence and Respiratory Tract Assessment) was initiated at 4 locations in the U.S. The serological assay presented here measuring IgG binding to the SARS-CoV-2 receptor binding domain (RBD) detected antibodies elicited by SARS-CoV-2 infection or vaccination with a 95.5% sensitivity and a 95.9% specificity. We used this assay to screen more than 3100 participants and selected 20 previously infected pre-immune and 32 immunologically naïve participants to analyze their antibody binding to RBD and viral neutralization (VN) responses following vaccination with two doses of either the Pfizer-BioNTech BNT162b2 or the Moderna mRNA-1273 vaccine. Vaccination not only elicited a more robust immune reaction than natural infection, but the level of neutralizing and anti-RBD antibody binding after vaccination is also significantly higher in pre-immune participants compared to immunologically naïve participants (p<0.0033). Furthermore, the administration of the second vaccination did not further increase the neutralizing or binding antibody levels in pre-immune participants (p=0.69). However, ~46% of the immunologically naïve participants required both vaccinations to seroconvert.

Detection of three novel translocations and specific common chromosomal break sites in malignant melanoma by spectral karyotyping

Chromosomal aberrations in malignant melanoma cells have been reported using standard chromosome banding analysis and comparative genomic hybridization. To identify marker chromosomes and translocations that are difficult to characterize by standard banding analysis, 15 early passage malignant melanoma cell lines were examined using spectral karyotyping. All 15 tumor cell lines had lost all or part of 1p and 10q. Losses of material on chromosome arms 4p (12/15), 6q (12/15), 9p (15/15), 12p (13/15), 12q (13/15), 13q (11/15), and 19q (14/15) were the next most frequent events. Gain of chromosome arms 1q (11/15), 6p (13/15), and 20q11 (14/15) was also observed. Interestingly, we identified translocations der(12)t(12;20)(q15;q11), der(19)t(10;19)(q23;q13), and der(12)t(12;19)(q13;q13) in 4/15 tumors. Three recurring translocations involving four of the most frequent break points were detected. The identification of recurring translocations and unique chromosome break points in melanoma will aid in the identification of the genes that are important in the neoplastic process.