Monoclonal antibody for COVID-19: Unveiling the recipe of a new cocktail

The coronavirus disease 2019 (COVID-19) pandemic has had a tremendous adverse impact on the global health system, public sector, and social aspects. It is unarguably the worst pandemic of the century. However, COVID-19 management is a mystery in front of us, and an authentic treatment is urgently needed. Various repurposed drugs, like ivermectin, remdesivir, tocilizumab, baricitinib, etc., have been used to treat COVID-19, but none are promising. Antibody therapy and their combinations are emerging modalities for treating moderate COVID-19, and they have shown the potential to reduce hospitalisations. One antibody monotherapy, bamlanivimab, and two cocktails, casirivimab/imdevimab and bamlanivimab/ esterivimab, have received authorization for emergency use by the United States Food and Drug Administration for the treatment of mild COVID-19 in high risk individuals. The European Emergency has made similar recommendations for use of the drug in COVID-19 patients without oxygen therapy. This brief review will focus on monoclonal antibodies and their combination cocktail therapy in managing COVID-19 infection.

Household secondary attack rate in mild COVID-19

Background

The coronavirus disease 2019 (COVID-19) pandemic has reached a staggering number of almost 280 million cases worldwide, with over 5.4 million deaths as of 29 December 2021. A further understanding of the factors related to the household spread of the infection might help to bring about specific protocols to curb such transmission.

Objective

This study aims to find the secondary attack rate (SAR) and factors affecting SAR among the households of mild COVID-19 cases.

Methods

An observational study was designed where data of patients admitted at All India Institute of Medical Sciences, New Delhi due to mild COVID-19 were collected, and outcome was noted after the discharge of the patient. Index cases who were the first in the household to have a positive infection only were included. Based on these data, the overall household SAR, factors related to the index case and contacts that affected transmissibility were noted.

Results

A total of 60 index cases having contacts with 184 household members were included in the present study. The household SAR was measured to be 41.85%. At least one positive case was present in 51.67% households. Children below 18 years old had lower odds of getting a secondary infection compared to adults and elderly [odds ratio (OR) = 0.46, 95%CI = 0.22-0.94, p = 0.0383). An exposure period of more than a week was significantly associated with a higher risk of infection (p = 0.029). The rate of transmissibility drastically declined with effective quarantine measures adopted by the index case (OR = 0.13, 95%CI = 0.06-0.26, p < 0.00001). Symptomatic index cases contributed more to the SAR than asymptomatic primaries (OR = 4.74, 95%CI = 1.03-21.82, P = 0.045). Healthcare worker index cases had lower rates of spread (OR = 0.29, 95%CI = 0.15-0.58, P = 0.0003).

Conclusion

The high SAR shows the household is a potential high-risk unit for transmissibility of COVID-19. Proper quarantine measures of all those exposed to the index case can mitigate such spread and lead to reduction of risk of COVID-19 within a household.

Association between obesity and hospitalization in mild COVID-19 adult outpatients in Brazil: a prospective cohort study

Objective

To evaluate the association between obesity and hospitalization in mild COVID-19 adult outpatients in Brazil.

Methods

Adults with signs and symptoms suggestive of acute SARS-CoV-2 infection who sought treatment in two hospital (public and private) emergency departments were prospectively enrolled. Patients with confirmed COVID-19 at inclusion were followed by phone calls at days D7, D14 and D28. Multivariable logistic regression models were employed to explore the association between obesity and other potential predictors for hospitalization.

Results

A total of 1,050 participants were screened, and 297 completed the 28-day follow-up and were diagnosed with COVID-19 by RT-PCR. The median age was 37.2 (IQR 29.7-44.6) years, and 179 (60.0%) were female. The duration of symptoms was 3.0 (IQR 2.0-5.0) days, and 10.0 (IQR 8.0-12.0) was the median number of symptoms at inclusion. Ninety-five (32.0%) individuals had obesity, and 233 (78.5%) had no previous medical conditions. Twenty-three participants (7.7%) required hospitalization during the follow-up period. After adjusting, obesity (BMI ≥ 30.0 kg/m2) (OR = 2.69, 95% CI 1.63-4.83, P < 0.001) and older age (OR = 1.05, 95% CI 1.01-1.09, P < 0.001) were significantly associated with higher risks of hospitalization.

Conclusion

Obesity, followed by aging, was the main factor associated with hospital admission for COVID-19 in a young population in a low-middle income country. Our findings highlighted the need to promote additional protection for individuals with obesity, such as vaccination, and to encourage lifestyle changes.

Humoral and cellular immune response levels at a 1-year follow-up after mild COVID-19

The primary objective of this study was to establish a 1-year follow-up of patients after mild COVID-19 with no or only short-term detection of antibodies shortly after disease. At 1 year after disease, cellular memory against SARS-CoV-2, as measured by IFN-γ release by T cells, was detected in 76% (38/50) of participants. The data suggest that even if antibody levels decline after the primary infection has resolved, a cellular immune response may be detectable for longer.

Prevalence and factors associated with symptom persistence: A prospective study of 429 mild COVID-19 outpatients

INTRODUCTION

Persistent symptoms have recently emerged as a clinical issue in COVID-19. We aimed to assess the prevalence and risk factors in symptomatic non-hospitalized individuals with mild COVID-19.

METHODS

We performed a prospective cohort study of symptomatic COVID-19 outpatients, from March to May 2020, with weekly phone calls from clinical onset until day 30 and up to day 60 in case of persistent symptoms. The main outcomes were the proportion of patients with complete recovery at day 30 and day 60 and factors associated with persistent symptoms.

RESULTS

We enrolled 429 individuals mostly women (72.5%) and healthcare workers (72.5%), with a median age of 41.6 years [IQR 30-51.5]. Symptoms included: cough (69.7%), asthenia (68.8%), anosmia (64.8%), headaches (64.6%), myalgia (62.7%), gastrointestinal symptoms (61.8%), fever (61.5%), and ageusia (60.8%). Mean duration of disease was 27 days (95%CI: 25-29). The rate of persistent symptoms was 46.8% at day 30 and 6.5% at day 60 consisting in asthenia (32.6%), anosmia (32.6%), and ageusia (30.4%). The probability of complete recovery was 56.3% (95%CI: 51.7-61.1) at day 30 and 85.6% (95%CI: 81.2-89.4) at day 60. Factors associated with persistent symptoms were age>40 (HR 0.61), female sex (HR 0.70), low cycle threshold (HR 0.78), and ageusia (HR 0.59).

CONCLUSIONS

COVID-19 - even in its mild presentation - led to persistent symptoms (up to one month) in nearly half of individuals. Identification of risk factors such as age, gender, ageusia and viral load is crucial for clinical management and argues for the development of antiviral agents.

Altered motor cortex physiology and dysexecutive syndrome in patients with fatigue and cognitive difficulties after mild COVID-19

Background and purpose

Fatigue and cognitive difficulties are reported as the most frequently persistent symptoms in patients after mild SARS‐CoV‐2 infection. An extensive neurophysiological and neuropsychological assessment of such patients was performed focusing on motor cortex physiology and executive cognitive functions.

Methods

Sixty‐seven patients complaining of fatigue and/or cognitive difficulties after resolution of mild SARS‐CoV‐2 infection were enrolled together with 22 healthy controls (HCs). Persistent clinical symptoms were investigated by means of a 16‐item questionnaire. Fatigue, exertion, cognitive difficulties, mood and ‘well‐being’ were evaluated through self‐administered tools. Utilizing transcranial magnetic stimulation of the primary motor cortex (M1) resting motor threshold, motor evoked potential amplitude, cortical silent period duration, short‐interval intracortical inhibition, intracortical facilitation, long‐interval intracortical inhibition and short‐latency afferent inhibition were evaluated. Global cognition and executive functions were assessed with screening tests. Attention was measured with computerized tasks.

Results

Post COVID‐19 patients reported a mean of 4.9 persistent symptoms, high levels of fatigue, exertion, cognitive difficulties, low levels of well‐being and reduced mental well‐being. Compared to HCs, patients presented higher resting motor thresholds, lower motor evoked potential amplitudes and longer cortical silent periods, concurring with reduced M1 excitability. Long‐interval intracortical inhibition and short‐latency afferent inhibition were also impaired, indicating altered GABA_B‐ergic and cholinergic neurotransmission. Short‐interval intracortical inhibition and intracortical facilitation were not affected. Patients also showed poorer global cognition and executive functions compared to HCs and a clear impairment in sustained and executive attention.

Conclusions

Patients with fatigue and cognitive difficulties following mild COVID‐19 present altered excitability and neurotransmission within M1 and deficits in executive functions and attention.

Efficacy of favipiravir in adults with mild COVID-19: a randomized, double-blind, multicenter, placebo-controlled trial clinical trial

Objective

To evaluate whether favipiravir reduces the time to viral clearance as documented by negative RT-PCR results for severe acute respiratory syndrome coronavirus 2 in mild cases of coronavirus disease 2019 (COVID-19) compared to placebo.

Methods

In this randomized, double-blinded, multicentre, and placebo-controlled trial, adults with PCR-confirmed mild COVID-19 were recruited in an outpatient setting at seven medical facilities across Saudi Arabia. Participants were randomized in a 1:1 ratio to receive either favipiravir 1800 mg by mouth twice daily on day 1 followed by 800 mg twice daily (n = 112) or a matching placebo (n = 119) for a total of 5 to 7 days. The primary outcome was the effect of favipiravir on reducing the time to viral clearance (by PCR test) within 15 days of starting the treatment compared to the placebo group. The trial included the following secondary outcomes: symptom resolution, hospitalization, intensive care unit admissions, adverse events, and 28-day mortality.

Results

Two hundred thirty-one patients were randomized and began the study (median age, 37 years; interquartile range (IQR): 32–44 years; 155 [67%] male), and 112 (48.5%) were assigned to the treatment group and 119 (51.5%) into the placebo group. The data and safety monitoring board recommended stopping enrolment because of futility at the interim analysis. The median time to viral clearance was 10 days (IQR: 6–12 days) in the favipiravir group and 8 days (IQR: 6–12 days) in the placebo group, with a hazard ratio of 0.87 for the favipiravir group (95% CI 0.571–1.326; p = 0.51). The median time to clinical recovery was 7 days (IQR: 4–11 days) in the favipiravir group and 7 days (IQR: 5–10 days) in the placebo group. There was no difference between the two groups in the secondary outcome of hospital admission. There were no drug-related severe adverse events.

Conclusion

In this clinical trial, favipiravir therapy in mild COVID-19 patients did not reduce the time to viral clearance within 15 days of starting the treatment.

Clinical outcomes of patients with mild COVID-19 following treatment with hydroxychloroquine in an outpatient setting

We appreciate the efforts of the authors in their study on the clinical outcome of hydroxychloroquine (HCQ) therapy in mild coronavirus disease 2019 (COVID-19) (Mokhtari et al., 2021). We would like to make some comments based on our understanding of the study.

Mild COVID-19 infection-predicting symptomatic phase and outcome: A study from AIIMS, New Delhi

Context:

Comprehensive management of mild COVID infection calls for better understanding of symptomatology in these group of patients as well as early identification and close monitoring of patients at risk, data on which is limited.

Aim:

To study association between inflammatory markers and clinical presentation with progression of disease and the duration of resolution of symptoms.

Settings and Design:

This is a retrospective study that has been conducted at a designated COVID -19 medical ward at AIIMS, New Delhi

Methods and Material:

Fifty healthcare workers and their dependents who were admitted with asymptomatic and mild COVID-19 infection were included. Their records were retrospectively reviewed, entered into a predesigned proforma and analyzed.

Results:

A total of 50 participants were included in the study of which 70% were healthcare workers. The patients were admitted with mild COVID illness out of which 22 (44%) were males. Most common symptom at presentation was fever (72%). Among patients who had mild disease versus those who progressed to moderate illness (n = 3), the patients with moderate illness were older [mean (SD): 57.33 (10.21) vs. 36.13 (14.05); P = 0.014] and had a longer duration of hospital stay [17 (1.41) days vs. 11.20 (3.86) days; P = 0.04]. Inflammatory markers, C-Reactive Protein (CRP) [2.46 vs. 0.20 (P = 0.024)], and Ferritin [306.15 vs. 72.53 (P = 0.023)] were higher in patients with moderate illness. There is also a significant correlation between the number of days taken for symptoms to resolve with Serum Ferritin (P = 0.007), CRP (P = 0.0256), and neutrophil lymphocyte ratio (NLR) (P = 0.044).

Conclusions:

Acute phase reactants/Inflammatory markers serve as good indicators of time taken to resolution of symptoms in acute COVID infection. NLR is a simple and inexpensive method to provide insight into symptomatic phase. These may be utility tools for primary care physician in the management in periphery and timely decision.

Follow-up of adults with noncritical COVID-19 two months after symptom onset

Objectives

To describe the clinical evolution and predictors of symptom persistence during 2 months' follow-up in adults with noncritical coronavirus disease 2019 (COVID-19).

Methods

We performed descriptive clinical follow-up (day (D) 7, D30 and D60) of 150 patients with noncritical COVID-19 confirmed by real-time reverse transcriptase PCR at Tours University Hospital from 17 March to 3 June 2020, including demographic, clinical and laboratory data collected from the electronic medical records and by phone call. Persisting symptoms were defined by the presence at D30 or D60 of at least one of the following: weight loss ≥5%, severe dyspnoea or asthenia, chest pain, palpitations, anosmia/ageusia, headache, cutaneous signs, arthralgia, myalgia, digestive disorders, fever or sick leave.

Results

At D30, 68% (103/150) of patients had at least one symptom; and at D60, 66% (86/130) had symptoms, mainly anosmia/ageusia: 59% (89/150) at symptom onset, 28% (40/150) at D30 and 23% (29/130) at D60. Dyspnoea concerned 36.7% (55/150) patients at D30 and 30% (39/130) at D60. Half of the patients (74/150) at D30 and 40% (52/130) at D60 reported asthenia. Persistent symptoms at D60 were significantly associated with age 40 to 60 years old, hospital admission and abnormal auscultation at symptom onset. At D30, severe COVID-19 and/or dyspnoea at symptom onset were additional factors associated with persistent symptoms.

Conclusions

Up to 2 months after symptom onset, two thirds of adults with noncritical COVID-19 had complaints, mainly anosmia/ageusia, dyspnoea or asthenia. A prolonged medical follow-up of patients with COVID-19 seems essential, whatever the initial clinical presentation.

Hanshiyi Formula, a medicine for Sars-CoV2 infection in China, reduced the proportion of mild and moderate COVID-19 patients turning to severe status: A cohort study

We formulated a traditional Chinese medicine (TCM) prescription, Hanshiyi Formula (HSYF), which was approved and promoted by the Wuhan Municipal Health Commission for treating mild and moderate coronavirus disease 2019 (COVID-19). We aimed to evaluate the effect of HSYF on the progression to severe disease in mild and moderate COVID-19 patients. We conducted a retrospective cohort study of patients with mild and moderate COVID-19 in a quarantine station in Wuchang District, Wuhan. Using the real-time Internet information collection application and Centers for Disease Control for the Wuchang District, patient data were collected through patient self-reports and follow-ups. HSYF intervention was defined as the exposure. The primary outcome was the proportion of patients who progressed to a severe disease status, and a stratification analysis was performed. Univariate and multivariate regression analyses were performed to identify influencing factors that may affect the outcome. Further, we used propensity score matching (PSM) to assess the effect of HSYF intervention on the conversion of mild and moderate to a severe disease status. Totally, 721 mild and moderate COVID-19 patients were enrolled, including 430 HSYF users (exposed group) and 291 non-users (control group). No cases in the exposed group and 19 (6.5 %, P < 0.001) cases in the control group progressed to severe disease, and the difference between the two groups (exposed group-control group) was −6.5 % [95 % confidence interval (CI): (−8.87 %, −4.13 %)]. Univariate regression analysis revealed sex (male), age, fever, cough, and fatigue as risk factors for progression to severe disease. After PSM, none of the HSYF users and 7 (4.7 %, P = 0.022) non-users transitioned to severe disease, and the difference between the two groups (exposed group-control group) was −4.7 % [95 % CI: (−8.2 %, −1.2 %)]. Multivariate regression analysis revealed that sex (male) [OR: 3.145; 95 % CI: 1.036–9.545; P = 0.043] and age (> 48 years) [odds ratio (OR): 1.044; 95 % CI: 1.001–1.088; P = 0.044] were independent risk factors for conversion to severe disease. Therefore, HSYF can significantly reduce the progression to severe disease in patients with mild and moderate COVID-19, which may effectively prevent and treat the disease. However, further larger clinical studies are required to verify our results.