Advances in Antibody Design and Antigenic Peptide Targeting 2.0.

Antibodies possess numerous important functions in diagnostics, both as therapeutics and as research tools [...].

bioTCIs: Middle-to-Macro Biomolecular Targeted Covalent Inhibitors Possessing Both Semi-Permanent Drug Action and Stringent Target Specificity as Potential Antibody Replacements.

Monoclonal antibody therapies targeting immuno-modulatory targets such as checkpoint proteins, chemokines, and cytokines have made significant impact in several areas, including cancer, inflammatory disease, and infection. However, antibodies are complex biologics with well-known limitations, including high cost for development and production, immunogenicity, a limited shelf-life because of aggregation, denaturation, and fragmentation of the large protein. Drug modalities such as peptides and nucleic acid aptamers showing high-affinity and highly selective interaction with the target protein have been proposed alternatives to therapeutic antibodies. The fundamental limitation of short in vivo half-life has prevented the wide acceptance of these alternatives. Covalent drugs, also known as targeted covalent inhibitors (TCIs), form permanent bonds to target proteins and, in theory, eternally exert the drug action, circumventing the pharmacokinetic limitation of other antibody alternatives. The TCI drug platform, too, has been slow in gaining acceptance because of its potential prolonged side-effect from off-target covalent binding. To avoid the potential risks of irreversible adverse drug effects from off-target conjugation, the TCI modality is broadening from the conventional small molecules to larger biomolecules possessing desirable properties (e.g., hydrolysis resistance, drug-action reversal, unique pharmacokinetics, stringent target specificity, and inhibition of protein-protein interactions). Here, we review the historical development of the TCI made of bio-oligomers/polymers (i.e., peptide-, protein-, or nucleic-acid-type) obtained by rational design and combinatorial screening. The structural optimization of the reactive warheads and incorporation into the targeted biomolecules enabling a highly selective covalent interaction between the TCI and the target protein is discussed. Through this review, we hope to highlight the middle to macro-molecular TCI platform as a realistic replacement for the antibody.

Recent Advances in Antibody Therapeutics.

Antibody-based therapeutics have achieved unprecedented success in treating various diseases, including cancers, immune disorders, and infectious diseases [...].

The COVID-19/Tuberculosis Syndemic and Potential Antibody Therapy for TB Based on the Lessons Learnt From the Pandemic.

2020 will be marked in history for the dreadful implications of the COVID-19 pandemic that shook the world globally. The pandemic has reshaped the normality of life and affected mankind in the aspects of mental and physical health, financial, economy, growth, and development. The focus shift to COVID-19 has indirectly impacted an existing air-borne disease, Tuberculosis. In addition to the decrease in TB diagnosis, the emergence of the TB/COVID-19 syndemic and its serious implications (possible reactivation of latent TB post-COVID-19, aggravation of an existing active TB condition, or escalation of the severity of a COVID-19 during TB-COVID-19 coinfection), serve as primary reasons to equally prioritize TB. On a different note, the valuable lessons learnt for the COVID-19 pandemic provide useful knowledge for enhancing TB diagnostics and therapeutics. In this review, the crucial need to focus on TB amid the COVID-19 pandemic has been discussed. Besides, a general comparison between COVID-19 and TB in the aspects of pathogenesis, diagnostics, symptoms, and treatment options with importance given to antibody therapy were presented. Lastly, the lessons learnt from the COVID-19 pandemic and how it is applicable to enhance the antibody-based immunotherapy for TB have been presented.

Recent advances in nanotechnology-based COVID-19 vaccines and therapeutic antibodies.

COVID-19 has caused a global pandemic and millions of deaths. It is imperative to develop effective countermeasures against the causative viral agent, SARS-CoV-2 and its many variants. Vaccines and therapeutic antibodies are the most effective approaches for preventing and treating COVID-19, respectively. SARS-CoV-2 enters host cells through the activities of the virus-surface spike (S) protein. Accordingly, the S protein is a prime target for vaccines and therapeutic antibodies. Dealing with particles with dimensions on the scale of nanometers, nanotechnology has emerged as a critical tool for rapidly designing and developing safe, effective, and urgently needed vaccines and therapeutics to control the COVID-19 pandemic. For example, nanotechnology was key to the fast-track approval of two mRNA vaccines for their wide use in human populations. In this review article, we first explore the roles of nanotechnology in battling COVID-19, including protein nanoparticles (for presentation of protein vaccines), lipid nanoparticles (for formulation with mRNAs), and nanobodies (as unique therapeutic antibodies). We then summarize the currently available COVID-19 vaccines and therapeutics based on nanotechnology.

Therapeutic antibodies - natural and pathological barriers and strategies to overcome them.

Antibody-based therapeutics have become a major class of therapeutics with over 120 recombinant antibodies approved or under review in the EU or US. This therapeutic class has experienced a remarkable expansion with an expected acceleration in 2021-2022 due to the extraordinary global response to SARS-CoV2 pandemic and the public disclosure of over a hundred anti-SARS-CoV2 antibodies. Mainly delivered intravenously, alternative delivery routes have emerged to improve antibody therapeutic index and patient comfort. A major hurdle for antibody delivery and efficacy as well as the development of alternative administration routes, is to understand the different natural and pathological barriers that antibodies face as soon as they enter the body up to the moment they bind to their target antigen. In this review, we discuss the well-known and more under-investigated extracellular and cellular barriers faced by antibodies. We also discuss some of the strategies developed in the recent years to overcome these barriers and increase antibody delivery to its site of action. A better understanding of the biological barriers that antibodies have to face will allow the optimization of antibody delivery near its target. This opens the way to the development of improved therapy with less systemic side effects and increased patients' adherence to the treatment.

Accelerating Coronavirus Disease 2019 Therapeutic Interventions and Vaccines-Selecting Compounds for Clinical Evaluation in Coronavirus Disease 2019 Clinical Trials.

Given the urgent need for coronavirus disease 2019 therapeutics, early in the pandemic the Accelerating Coronavirus Disease 2019 Therapeutic Interventions and Vaccines (ACTIV) public-private partnership rapidly designed a unique therapeutic agent intake and assessment process for candidate treatments of coronavirus disease 2019. These treatments included antivirals, immune modulators, severe acute respiratory syndrome coronavirus 2 neutralizing antibodies, and organ-supportive treatments at both the preclinical and clinical stages of development. The ACTIV Therapeutics-Clinical Working Group Agent Prioritization subgroup established a uniform data collection process required to perform an assessment of any agent type using review criteria that were identified and differentially weighted for each agent class. The ACTIV Therapeutics-Clinical Working Group evaluated over 750 therapeutic agents with potential application for coronavirus disease 2019 and prioritized promising candidates for testing within the master protocols conducted by ACTIV. In addition, promising agents among preclinical candidates were selected by ACTIV to be matched with laboratories that could assist in executing rigorous preclinical studies. Between April 14, 2020, and May 31, 2021, the Agent Prioritization subgroup advanced 20 agents into the Accelerating Coronavirus Disease 2019 Therapeutic Interventions and Vaccines master protocols and matched 25 agents with laboratories to assist with preclinical testing.

Inhaled antibodies: Quality and performance considerations.

The use of antibodies in the treatment of lung diseases is of increasing interest especially as the search for COVID-19 therapies has unfolded. Historically, the use of antibody therapy was based on multiple targets including receptors involved in local hyper-reactivity in asthma, viruses and micro-organisms involved in a variety of pulmonary infectious disease. Generally, protein therapeutics pose challenges with respect to formulation and delivery to retain activity and assure therapy. The specificity of antibodies amplifies the need for attention to molecular integrity not only in formulation but also during aerosol delivery for pulmonary administration. Drug product development can be viewed from considerations of route of administration, dosage form, quality, and performance measures. Nebulizers and dry powder inhalers have been used to deliver protein therapeutics and each has its advantages that should be matched to the needs of the drug and the disease. This review offers insight into quality and performance barriers and the opportunities that arise from meeting them effectively.

Chicken IgY Antibodies Provide Mucosal Barrier against SARS-CoV-2 Virus and Other Pathogens.

BACKGROUND: This mini review includes two case descriptions. It introduces the use of chicken egg yolk antibody (IgY) solutions in the prevention and cure of viral and bacterial infections. Application for the protection against severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), rotavirus, and influenza viruses, as well as for the eradication of Pseudomonas aeruginosa, caries, various enteric bacteria and other pathogens, and toxins have been developed. This approach is a fast, reliable, safe, and tested method for producing molecular shield and protection against emerging pathogens and epidemics. In the current pandemic situation caused by coronavirus disease-2019 (COVID-19), this method of passive immunization could be applied for rapid protection against modifiable agents. The specific IgY antibodies start to accumulate into egg yolks about 3 weeks after the immunization of the chicken. The product can be collected safely, as the antigen is not found in the eggs. This method for microbial safety uses natural means and commonly used food substances, which have been tested and could be produced for both blocking epidemics and applying personalized medicine.

Antibodies to watch in 2021.

In this 12th annual installment of the Antibodies to Watch article series, we discuss key events in antibody therapeutics development that occurred in 2020 and forecast events that might occur in 2021. The coronavirus disease 2019 (COVID-19) pandemic posed an array of challenges and opportunities to the healthcare system in 2020, and it will continue to do so in 2021. Remarkably, by late November 2020, two anti-SARS-CoV antibody products, bamlanivimab and the casirivimab and imdevimab cocktail, were authorized for emergency use by the US Food and Drug Administration (FDA) and the repurposed antibodies levilimab and itolizumab had been registered for emergency use as treatments for COVID-19 in Russia and India, respectively. Despite the pandemic, 10 antibody therapeutics had been granted the first approval in the US or EU in 2020, as of November, and 2 more (tanezumab and margetuximab) may be granted approvals in December 2020.* In addition, prolgolimab and olokizumab had been granted first approvals in Russia and cetuximab saratolacan sodium was first approved in Japan. The number of approvals in 2021 may set a record, as marketing applications for 16 investigational antibody therapeutics are already undergoing regulatory review by either the FDA or the European Medicines Agency. Of these 16 mAbs, 11 are possible treatments for non-cancer indications and 5 are potential treatments for cancer. Based on the information publicly available as of November 2020, 44 antibody therapeutics are in late-stage clinical studies for non-cancer indications, including 6 for COVID-19, and marketing applications for at least 6 (leronlimab, tezepelumab, faricimab, ligelizumab, garetosmab, and fasinumab) are planned in 2021. In addition, 44 antibody therapeutics are in late-stage clinical studies for cancer indications. Of these 44, marketing application submissions for 13 may be submitted by the end of 2021. *Note added in proof on key events announced during December 1-21, 2020: margetuximab-cmkb and ansuvimab-zykl were approved by FDA on December 16 and 21, 2020, respectively; biologics license applications were submitted for ublituximab and amivantamab.

Cytokine release syndrome: inhibition of pro-inflammatory cytokines as a solution for reducing COVID-19 mortality.

Coronavirus disease (COVID-19) reached pandemic proportions at the beginning of 2020 and continues to be a worldwide concern. End organ damage and acute respiratory distress syndrome are the leading causes of death in severely or critically ill patients. The elevated cytokine levels in severe patients in comparison with mildly affected patients suggest that cytokine release syndrome (CRS) occurs in the severe form of the disease. In this paper, the significant role of pro-inflammatory cytokines, including IL-1, IL-6, and TNF-alpha, and their mechanism of action in the CRS cascade is explained. Potential therapeutic approaches involving anti-IL-6 and anti-TNF-alpha antibodies to fight COVID-19 and reduce mortality rate in severe cases are also discussed.

Ferritin as a Platform for Creating Antiviral Mosaic Nanocages: Prospects for Treating COVID-19.

Infectious diseases are a continues threat to human health and the economy worldwide. The latest example is the global pandemic of COVID-19 caused by SARS-CoV-2. Antibody therapy and vaccines are promising approaches to treat the disease; however, they have bottlenecks: they might have low efficacy or narrow breadth due to the continuous emergence of new strains of the virus or antibodies could cause antibody-dependent enhancement (ADE) of infection. To address these bottlenecks, I propose the use of 24-meric ferritin for the synthesis of mosaic nanocages to deliver a cocktail of antibodies or nanobodies alone or in combination with another therapeutic, like a nucleotide analogue, to mimic the viral entry process and deceive the virus, or to develop mosaic vaccines. I argue that available data showing the effectiveness of ferritin-antibody conjugates in targeting specific cells and ferritin-haemagglutinin nanocages in developing influenza vaccines strongly support my proposals.

The role of the thymus in COVID-19 disease severity: implications for antibody treatment and immunization.

The thymus is a largely neglected organ but plays a significant role in the regulation of adaptive immune responses. The effect of aging on the thymus and immune senescence is well established, and the resulting inflammaging is found to be implicated in the development of many chronic diseases including atherosclerosis, hypertension and type 2 diabetes. Both aging and diseases of inflammaging are associated with severe COVID-19 disease, and a dysfunctional thymus may be a predisposing factor. In addition, insults on the thymus during childhood may lead to abnormal thymic function and may explain severe COVID-19 disease among younger individuals; therefore, measurement of thymic function may assist COVID-19 care. Those with poor thymic function may be treated prophylactically with convalescent serum or recombinant antibodies, and they may respond better to high-dose or adjuvanted COVID-19 vaccines. Treatments inducing thymic regeneration may improve patients' overall health and may be incorporated in COVID-19 management.

SARS-CoV-2 mediated lung inflammatory responses in host: targeting the cytokine storm for therapeutic interventions.

The recent exposure of novel coronavirus strain, severe acute respiratory syndrome (SARS-CoV-2) has spread to different countries at an alarming rate. Faster transmission rate and genetic modifications have provoked scientists to search for an immediate solution. With an increasing death rate, it becomes important to throw some light on the life cycle of the virus and its associated pathogenesis in the form of lung inflammation through cytokine storm (CS) production. This paper highlights the different stages of viral-mediated inflammatory responses in the host respiratory system. Previously, known anti-inflammatory drugs and therapeutic strategies that might show potential in controlling the CS of Coronavirus disease-2019 (COVID-19) is also mentioned in this study. Our critical analysis provides insights into the inflammation cycle induced in the lungs by early virus replication, downregulation and shedding of angiotensin-converting enzyme 2 (ACE2), and in the CS production. Identification of suitable targets within the inflammatory pathways for devising the therapeutic strategies useful in controlling the prognosis of COVID-19 finds a special mention in this article. However, antibody-dependent enhancement is the key aspect to consider before testing any drug/compound for therapeutic purposes. Our in-depth analysis would provide similarities and differences between the inflammatory responses induced by SARS-CoV and SARS-CoV-2, providing an excellent avenue to further look at how earlier outbreaks of coronaviruses were controlled and where new steps are required?

Possible Targets and Therapies of SARS-CoV-2 Infection.

The global spread of the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) that causes COVID-19 has become a source of grave medical and socioeconomic concern to human society. Since its first appearance in the Wuhan region of China in December 2019, the most effective measures of managing the spread of SARS-CoV-2 infection have been social distancing and lockdown of human activity; the level of which has not been seen in our generations. Effective control of the viral infection and COVID-19 will ultimately depend on the development of either a vaccine or therapeutic agents. This article highlights the progresses made so far in these strategies by assessing key targets associated with the viral replication cycle. The key viral proteins and enzymes that could be targeted by new and repurposed drugs are discussed.