Efficacy, safety, and lot-to-lot immunogenicity of an inactivated SARS-CoV-2 vaccine (BBV152): interim results of a randomised, double-blind, controlled, phase 3 trial

BACKGROUND

We report the clinical efficacy against COVID-19 infection of BBV152, a whole virion inactivated SARS-CoV-2 vaccine formulated with a toll-like receptor 7/8 agonist molecule adsorbed to alum (Algel-IMDG) in Indian adults.

METHODS

We did a randomised, double-blind, placebo-controlled, multicentre, phase 3 clinical trial in 25 Indian hospitals or medical clinics to evaluate the efficacy, safety, and immunological lot consistency of BBV152. Adults (age ≥18 years) who were healthy or had stable chronic medical conditions (not an immunocompromising condition or requiring treatment with immunosuppressive therapy) were randomised 1:1 with a computer-generated randomisation scheme (stratified for the presence or absence of chronic conditions) to receive two intramuscular doses of vaccine or placebo administered 4 weeks apart. Participants, investigators, study coordinators, study-related personnel, the sponsor, and nurses who administered the vaccines were masked to treatment group allocation; an unmasked contract research organisation and a masked expert adjudication panel assessed outcomes. The primary outcome was the efficacy of the BBV152 vaccine in preventing a first occurrence of laboratory-confirmed (RT-PCR-positive) symptomatic COVID-19 (any severity), occurring at least 14 days after the second dose in the per-protocol population. We also assessed safety and reactogenicity throughout the duration of the study in all participants who had received at least one dose of vaccine or placebo. This report contains interim results (data cutoff May 17, 2021) regarding immunogenicity and safety outcomes (captured on days 0 to 56) and efficacy results with a median of 99 days for the study population. The trial was registered on the Indian Clinical Trials Registry India, CTRI/2020/11/028976, and ClinicalTrials.gov, NCT04641481 (active, not recruiting).

FINDINGS

Between Nov 16, 2020, and Jan 7, 2021, we recruited 25 798 participants who were randomly assigned to receive BBV152 or placebo; 24 419 received two doses of BBV152 (n=12 221) or placebo (n=12 198). Efficacy analysis was dependent on having 130 cases of symptomatic COVID-19, which occurred when 16 973 initially seronegative participants had at least 14 days follow-up after the second dose. 24 (0·3%) cases occurred among 8471 vaccine recipients and 106 (1·2%) among 8502 placebo recipients, giving an overall estimated vaccine efficacy of 77·8% (95% CI 65·2-86·4). In the safety population (n=25 753), 5959 adverse events occurred in 3194 participants. BBV152 was well tolerated; the same proportion of participants reported adverse events in the vaccine group (1597 [12·4%] of 12 879) and placebo group (1597 [12·4%] of 12 874), with no clinically significant differences in the distributions of solicited, unsolicited, or serious adverse events between the groups, and no cases of anaphylaxis or vaccine-related deaths.

INTERPRETATION

BBV152 was highly efficacious against laboratory-confirmed symptomatic COVID-19 disease in adults. Vaccination was well tolerated with no safety concerns raised in this interim analysis.

FUNDING

Bharat Biotech International and Indian Council of Medical Research.

Early shedding of membrane-bounded ACE2 could be an indicator for disease severity in SARS-CoV-2

SARS-CoV-2 uses membrane bound Angiotensin-Converting Enzyme 2 (ACE2) as a key host receptor for its entry. However, inconsistent results are available in terms of shedding of membrane ACE2 and circulating levels of soluble ACE2 during SARS-CoV-2. To ascertain soluble ACE2 as an effective biomarker for the prediction of COVID-19 outcome, in the present study, we investigated the levels of plasma ACE2 during the early phase of infection in COVID-19 patients. The study involved a total of 42 COVID-19 patients along with 10 healthy controls. Plasma levels of ACE2 was determined using ELISA at the time of admission and on day 7 post admission. The association of sACE2 with D-dimer a marker for hyper-coagulation was performed using a dependence test. Compared to healthy controls, SARS-CoV-2 cases has shown a huge increase in the sACE2 at the time of admission. During the course of infection, we found a significant increase (P ≤ 0.001) in sACE2 in severe cases compared to moderate. There was a strong increase in sACE2 in cases with hypertension and diabetes mellitus. Interestingly, a strong positive correlation (P ≤ 0.001) was obtained between sACE2 and D-dimer. Thus, an excessive shedding of ACE2 during the early phase is a common phenomenon in severe form of the SARS-CoV-2. Along with D-dimer, the sACE2 levels could serve as a clinical biomarker for the prediction of disease outcome. However further studies are needed to ascertain its role in host-virus interplay.

Neutralizing the free radicals could alleviate the disease severity following an infection by positive strand RNA viruses

Free radical release due to oxidative stress is gaining importance in the field of viral pathogenesis. Recent studies suggest the involvement of oxidative stress and ROS levels in regulating disease virulence during RNA virus infection. Most of the RNA virus infections lead to vascular dysfunction and disease severity. However, the biology of free radicals in maintaining vascular endothelium integrity is not completely understood. In the present review, we discuss some of the common features in positive-strand RNA virus infections such as dengue and SARS-CoV-2 and suggest that anti-oxidant therapy could pave the way to develop therapeutic strategies in combating emerging and re-emerging RNA viruses.

Effectiveness of Adjuvant Yoga Therapy in Diabetic Lung: A Randomized Control Trial

Context

Recent studies provide ample evidence of the benefits of yoga in various chronic disorders. Diabetes mellitus is a group of metabolic diseases characterized by chronic hyperglycemia and Sandler coined the term "Diabetic Lung" for the abnormal pulmonary function detected in diabetic patients due underlying pulmonary dysfunction. Yoga therapy may help in achieving better pulmonary function along with enhanced glycaemic control and overall health benefits.

Aim

To study the effect of adjuvant yoga therapy in diabetic lung through spirometry.

Settings and Design

Randomized control trial was made as interdisciplinary collaborative work between departments of Yoga Therapy, Pulmonary Medicine and Endocrinology, of MGMC & RI, Sri Balaji Vidyapeeth Puducherry.

Materials and Methods

72 patients of diabetic lung as confirmed by spirometry (<70% of expected) were randomized into control group (n=36) who received only standard medical treatment and yoga group (n=36) who received yoga training thrice weekly for 4 months along with standard medical management. Yoga therapy protocol included yogic counseling, preparatory practices, Asanas or static postures, Pranayama or breathing techniques and relaxation techniques. Hathenas of the Gitananda Yoga tradition were the main practices used. Spirometry was done at the end of the study period. Data was analyzed by Student's paired and unpaired 't' test as it passed normality.

Results

There was a statistically significant (P < 0.05) reduction in weight, and BMI along with a significant (P < 0.01) improvement in pulmonary function (FEV₁, FVC) in yoga group as compared to control group where parameters worsened over study period.

Conclusion

It is concluded from the present RCT that yoga has a definite role as an adjuvant therapy as it enhances standard medical care and hence is even more significant in routine clinical management of diabetes, improving physical condition and pulmonary function.

Exploring the regulatory role of small RNAs in modulating host-pathogen interactions: implications for bacterial and viral infections

MicroRNAs (miRNAs) and transfer RNA-derived stress-induced RNAs (tiRNAs) have emerged as crucial players in the post-transcriptional regulation of gene expression in various cellular processes, including immunity and host defense against infections. In recent years, increasing evidence has highlighted their complex role in influencing the host response during viral and bacterial infections. miRNAs have been shown to play multiple roles in host-pathogen interaction like TLR activation and altered disease virulence during bacterial infections. In the context of viral infections, miRNAs are involved in regulating viral replication, pathogenesis, and immune evasion. Similarly, tiRNAs have recently emerged as novel players in bacterial and viral infections such as modulating bacterial growth, adaptation to stress conditions, host antiviral responses, and impacting viral replication and pathogenesis. This review provides a comprehensive analysis of the potential of miRNA expression profiles as diagnostic biomarkers to differentiate between bacterial and viral infections. Further discusses the key pathways through which small RNAs regulate bacterial and viral infection-related diseases.

Understanding COVID-19 outcome: Exploring the prognostic value of soluble biomarkers indicative of endothelial impairment

Host proteins released by the activated endothelial cells during SARS-CoV-2 infection are implicated to be involved in coagulation and endothelial dysfunction. However, the underlying mechanism that governs the vascular dysfunction and disease severity in COVID-19 remains obscure. The study evaluated the serum levels of Bradykinin, Kallikrein, SERPIN A, and IL-18 in COVID-19 (N-42 with 20 moderate and 22 severe) patients compared to healthy controls (HC: N-10) using ELISA at the day of admission (DOA) and day 7 post-admission. The efficacy of the protein levels in predicting disease severity was further determined using machine learning models. The levels of bradykinins and SERPIN A were higher (P ≤ 0.001) in both severe and moderate cases on day 7 post-admission compared to DOA. All the soluble proteins studied were found to elevated (P ≤ 0.01) in severe compared to moderate in day 7 and were positively correlated (P ≤ 0.001) with D-dimer, a marker for coagulation. ROC analysis identified that SERPIN A, IL-18, and bradykinin could predict the clinical condition of COVID-19 with AUC values of 1, 0.979, and 1, respectively. Among the models trained using univariate model analysis, SERPIN A emerged as a strong prognostic biomarker for COVID-19 disease severity. The serum levels of SERPIN A in conjunction with the coagulation marker D-dimer, serve as a predictive indicator for COVID-19 clinical outcomes. However, studies are required to ascertain the role of these markers in disease virulence.

Serosurveillance of COVID-19 amongst health care workers in a teaching institution - A prospective cohort study in Puducherry district

Introduction

The rapid spread and mutation rate of severe acute respiratory syndrome corona virus (SARS-CoV2) demands continuous monitoring in terms of genomic and serosurvival. The current study is designed to track the seroprevalence of health care workers (HCWs) postvaccination, as they may be more susceptible to contracting the SARS-CoV-2 infection compared to the general population.

Objective

The objective was to identify the seroprevalence rate for SARS-CoV-2 immunoglobulin G (IgG) antibody (N, S1, S2) amongst HCWs of various levels of exposure working in a tertiary care teaching hospital in Puducherry.

Materials and Methods

The present study followed a nonprobability consecutive sampling technique, which involved 216 study participants HCWs from the hospital. IgG antibody levels were measured using EUROIMMUNE Anti SARS-COV-2 ELISA KIT (IG g) ELISA at two points: firstly, 2 weeks after the second dose of vaccination, followed by 2 weeks after the booster dose.

Results

Out of the total 216 participants enrolled in the survey, there were 140 males and 76 females, and the maximum number of candidates studied were in the 41-50 age group. Almost 46.7% of the HCWs who participated in the study were seropositive for SARS-CoV-2 in the case of those who were high-risk exposed, while only 30.4% were amongst those who were low-risk exposed. The proportion of study participants who became seropositive increased considerably after the booster dose (65.7%), from 38.0% when tested three months after infection.

Conclusion

A significant increase in antibody titres amongst high-risk HCWs postboost vaccination demands continuous monitoring of soluble IgG levels for recommendations of vaccination schedules.