Phase 2 safety and antiviral activity of SAB-185, a novel polyclonal antibody therapy for non-hospitalized adults with COVID-19

SAB-185, a novel fully-human IgG polyclonal immunoglobulin product, underwent phase 2 evaluation for non-hospitalized adults with mild-moderate COVID-19.Participants received intravenous SAB-185 3,840 units/kg (low-dose) or placebo, or 10,240 units/kg (high-dose) or placebo. Primary outcome measures were nasopharyngeal SARS-CoV-2 RNA <lower limit of quantification (LLoQ) at study days 3, 7, and 14, time to symptomatic improvement, and safety through day 28.Two-hundred thirteen participants received low-dose SAB-185/placebo (n=107/106) and 215 high-dose SAB-185/placebo (n=110/105). The proportions with SARS-CoV-2 RNA <LLoQ were higher for SAB-185 versus placebo at days 3 and 7 and similar at day 14, and significantly higher at day 7 for high-dose SAB versus placebo only, relative risk (95% CI) 1.23 (1.01, 1.49). At day 3, SARS-CoV-2 RNA levels were lower with low-dose and high-dose SAB-185 versus placebo, differences in medians of -0.78 log10copies/mL (p=0.08) and -0.71 log10copies/mL (p=0.10), respectively. No difference was observed in time to symptom improvement: median 11/10 days (p=0.24) for low-dose SAB-185/placebo and 8/10 days (p=0.50) for high-dose SAB-185/placebo. Grade ≥3 adverse events occurred in 5%/13% of low-dose SAB-185/placebo and 9%/12% of high-dose SAB-185/placebo.SAB-185 was safe and generally well tolerated and demonstrated modest antiviral activity in predominantly low-risk non-hospitalized adults with COVID-19

Investigating type I error rate of clinical trials after using stratified permuted block randomization and the permutation test

In this project, we compared different analysis methods following stratified permuted block design, a commonly used method of covariate-adaptive randomization in clinical trials, the permutation test, and the traditional t-test, or the t-value for treatment from the full model in linear regression. Type I error rates were studied under three different scenarios. The t-test yielded very conservative type I error rates for the three scenarios when covariate information, which was used in covariate-adaptive design, was not included in the data analysis. We proposed to use the permutation test to fix this problem, and found that the type I error rates were preserved at the nominal level with our proposed methods. Preserving the nominal type I error rates is of special importance to validate the clinical trial results. Having valid results is crucial in determining whether or not a treatment is worth the potential side effects and cost to patients. If the results do not reflect the true effect, then an intervention that may be more harmful or less effective than anticipated could reach the target populations without having a true benefit. Ensuring clinical trial results are valid is very important from ethical, financial, and physical standpoints. Treatments that may cause too much harm or are too expensive to patients should be properly assessed, since patients would ultimately want to invest in proven treatments that will help improve their health and quality of life. In addition, when evaluating treatments, using covariate information in the study design and analysis is beneficial since certain covariates might affect the treatment in different ways. However, excluding randomization covariates from the data analysis will lead to conservative type I error. This project successfully investigated the data analysis methods to preserve the nominal type I error rate

Antiretroviral Therapy Initiation Is Associated With Decreased Visceral and Subcutaneous Adipose Tissue Density in People Living With Human Immunodeficiency Virus

BackgroundAdipose tissue (AT) alterations are common in people living with human immunodeficiency virus (PLWH). Decreases in AT density suggest disrupted adipocyte function/hypertrophy. We assessed changes in AT density after antiretroviral therapy (ART) initiation and associations with immunometabolic parameters.MethodsIn a prospective randomized clinical trial of ART initiation, L4-L5 abdominal CT scans measured subcutaneous AT (SAT) and visceral AT (VAT) area and density in treatment-naive PLWH randomized to tenofovir-emtricitabine plus ritonavir-boosted atazanavir, ritonavir-boosted darunavir, or raltegravir. Linear regression models compared week 0 and week 96 levels, and 96-week changes, in SAT and VAT density (in Hounsfield units [HU]). Spearman correlations assessed relationships between AT density and immunometabolic parameters.ResultsOf the 228 participants, 89% were male and 44% were white non-Hispanic. Median age was 36 years, baseline HIV-1 RNA was 4.6 log10 copies/mL, and CD4+ T-cell count was 344 cells/μL. Over 96 weeks, SAT and VAT HU decreased significantly in all arms. Less dense week 96 SAT and VAT density correlated with higher high-density lipoprotein (HDL) cholesterol and adiponectin (r = 0.19-0.30) levels and lower interleukin 6, non-HDL cholesterol, triglyceride, leptin, and homeostatic model assessment of insulin resistance (r = -0.23 to -0.68) levels at week 96 after adjusting for baseline CD4+ T-cell count, HIV-1 RNA, and baseline AT area.ConclusionsFollowing virologic suppression, lower SAT and VAT density was associated with greater plasma measures of systemic inflammation, lipid disturbances, and insulin resistance independent of AT area, suggesting that changes in AT density with ART may lead to adverse health outcomes independent of AT quantity.Clinical trials registrationNCT00851799

Poorer Muscle Quality and Quantity With ART Initiation Is Associated With Greater Inflammation and Immune Activation

BackgroundWe have previously shown that the initiation of antiretroviral therapy (ART) is associated with a decrease in skeletal muscle density (greater fat accumulation), suggesting that gains in lean body mass seen in many ART studies may reflect gains in low quality, fatty muscle. Here, we explore whether skeletal muscle density and area are associated with markers of inflammation and immune activation.MethodsART-naïve people with HIV were randomized to raltegravir or ritonavir-boosted atazanavir or darunavir, each with tenofovir disoproxil fumarate/emtricitabine. Abdominal computed tomography scans from baseline and week 96 were reanalyzed for psoas density and area and correlations explored with inflammation [interleukin-6 (IL-6) and high-sensitivity C-reactive protein] and immune activation [soluble CD14 (sCD14), soluble CD163 (sCD163), and %CD38+HLADR+ on CD4+ or CD8+ T cells].ResultsTwo hundred twenty-two participants had available inflammation/immune activation markers and paired computed tomography scans. At baseline, lower psoas density (greater fat) correlated with higher IL-6 (r = -0.26, P < 0.001) and sCD163 (r -0.15, P = 0.03) and lower lean psoas area correlated with higher IL-6, high-sensitivity C-reactive protein, sCD14, sCD163, and %CD38+HLADR+ on CD4+ T cells (r = -0.30-0.13; all P ≤ 0.05). From baseline to week 96, greater percent decrease in total psoas density (more fat) correlated with greater increase in IL-6 (r = -0.14; P = 0.04); greater % decrease in lean psoas area correlated greater increases in IL-6, sCD14, sCD163, and %CD38+HLADR+ on CD8+ T cells (r = -0.15 to -0.18; all P < 0.04).ConclusionsGreater fat infiltration within the psoas muscle (lower density) and greater loss in lean psoas muscle area were associated with higher inflammation and immune activation, which may portend important effects on muscle function and cardiometabolic risk

Phase 2 Safety and Antiviral Activity of SAB-185, a Novel Polyclonal Antibody Therapy for Nonhospitalized Adults With COVID-19

BackgroundSAB-185, a novel fully human IgG polyclonal immunoglobulin product, underwent phase 2 evaluation for nonhospitalized adults with mild-moderate coronavirus disease 2019 (COVID-19).MethodsParticipants received intravenous SAB-185 3840 units/kg (low-dose) or placebo, or 10 240 units/kg (high-dose) or placebo. Primary outcome measures were nasopharyngeal severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA < lower limit of quantification (LLOQ) at study days 3, 7, and 14, time to symptomatic improvement, and safety through day 28.ResultsTwo-hundred thirteen participants received low-dose SAB-185/placebo (n = 107/106) and 215 high-dose SAB-185/placebo (n = 110/105). The proportions with SARS-CoV-2 RNA < LLOQ were higher for SAB-185 versus placebo at days 3 and 7 and similar at day 14, and significantly higher at day 7 for high-dose SAB-185 versus placebo only, relative risk 1.23 (95% confidence interval, 1.01-1.49). At day 3, SARS-CoV-2 RNA levels were lower with low-dose and high-dose SAB-185 versus placebo: differences in medians of -0.78 log10 copies/mL (P = .08) and -0.71 log10 copies/mL (P = .10), respectively. No difference was observed in time to symptom improvement: median 11/10 days (P = .24) for low-dose SAB-185/placebo and 8/10 days (P = .50) for high-dose SAB-185/placebo. Grade ≥3 adverse events occurred in 5%/13% of low-dose SAB-185/placebo and 9%/12% of high-dose SAB-185/placebo.ConclusionsSAB-185 was safe and generally well tolerated and demonstrated modest antiviral activity in predominantly low-risk nonhospitalized adults with COVID-19. Clinical Trials Registration. NCT04518410