Development of Therapeutic and Prophylactic Zinc Compositions for Use against COVID-19: A Glimpse of the Trends, Inventions, and Patents

Zinc complexes of chloroquine and hydroxychloroquine versus the mixtures of their components: Structures, solution equilibria/speciation and cellular zinc uptake

The zinc complexes of chloroquine (CQ; [Zn(CQH+)Cl3]) and hydroxychloroquine (HO-CQ; [Zn(HO-CQH+)Cl3]) were synthesized and characterized by X-Ray structure analysis, FT-IR, NMR, UV-Vis spectroscopy, and cryo-spray mass spectrometry in solid state as well as in aqueous and organic solvent solutions, respectively. In acetonitrile, up to two Zn2+ ions bind to CQ and HO-CQ through the tertiary amine and aromatic nitrogen atoms (KN-aminCQ = (3.8 ± 0.5) x 104 M-1 and KN-aromCQ = (9.0 ± 0.7) x 103 M-1 for CQ, and KN-aminHO-CQ = (3.3 ± 0.4) x 104 M-1 and KN-aromHO-CQ = (1.6 ± 0.2) x 103 M-1 for HO-CQ). In MOPS buffer (pH 7.4) the coordination proceeds through the partially deprotonated aromatic nitrogen, with the corresponding equilibrium constants of KN-arom(aq)CQ = (3.9 ± 1.9) x 103 M-1and KN-arom(aq)HO-CQ = (0.7 + 0.4) x 103 M-1 for CQ and HO-CQ, respectively. An apparent partition coefficient of 0.22 was found for [Zn(CQH+)Cl3]. Mouse embryonic fibroblast (MEF) cells were treated with pre-synthesized [Zn((HO-)CQH+)Cl3] complexes and corresponding ZnCl2/(HO-)CQ mixtures and zinc uptake was determined by application of the fluorescence probe and ICP-OES measurements. Administration of pre-synthesized complexes led to higher total zinc levels than those obtained upon administration of the related zinc/(hydroxy)chloroquine mixtures. The differences in the zinc uptake between these two types of formulations were discussed in terms of different speciation and character of the complexes. The obtained results suggest that intact zinc complexes may exhibit biological effects distinct from that of the related zinc/ligand mixtures.

The Anti-Oxidative, Anti-Inflammatory, Anti-Apoptotic, and Anti-Necroptotic Role of Zinc in COVID-19 and Sepsis

Zinc is a structural component of proteins, functions as a catalytic co-factor in DNA synthesis and transcription of hundreds of enzymes, and has a regulatory role in protein-DNA interactions of zinc-finger proteins. For many years, zinc has been acknowledged for its anti-oxidative and anti-inflammatory functions. Furthermore, zinc is a potent inhibitor of caspases-3, -7, and -8, modulating the caspase-controlled apoptosis and necroptosis. In recent years, the immunomodulatory role of zinc in sepsis and COVID-19 has been investigated. Both sepsis and COVID-19 are related to various regulated cell death (RCD) pathways, including apoptosis and necroptosis. Lack of zinc may have a negative effect on many immune functions, such as oxidative burst, cytokine production, chemotaxis, degranulation, phagocytosis, and RCD. While plasma zinc concentrations decline swiftly during both sepsis and COVID-19, this reduction is primarily attributed to a redistribution process associated with the inflammatory response. In this response, hepatic metallothionein production increases in reaction to cytokine release, which is linked to inflammation, and this protein effectively captures and stores zinc in the liver. Multiple regulatory mechanisms come into play, influencing the uptake of zinc, the binding of zinc to blood albumin and red blood cells, as well as the buffering and modulation of cytosolic zinc levels. Decreased zinc levels are associated with increasing severity of organ dysfunction, prolonged hospital stay and increased mortality in septic and COVID-19 patients. Results of recent studies focusing on these topics are summarized and discussed in this narrative review. Existing evidence currently does not support pharmacological zinc supplementation in patients with sepsis or COVID-19. Complementation and repletion should follow current guidelines for micronutrients in critically ill patients. Further research investigating the pharmacological mechanism of zinc in programmed cell death caused by invasive infections and its therapeutic potential in sepsis and COVID-19 could be worthwhile.

QcrB inhibition as a potential approach for the treatment of tuberculosis: A review of recent developments, patents, and future directions

The unmet medical need for drug-resistant tuberculosis (DRTB) is a significant concern. Accordingly, identifying new drug targets for tuberculosis (TB) treatment and developing new therapies based on these drug targets is one of the strategies to tackle DRTB. QcrB is an innovative drug target to create treatments for DRTB. This article highlights QcrB inhibitors and their therapeutic compositions for treating TB. The literature for this article was gathered from PubMed and free patent databases utilizing different keywords related to QcrB inhibitor-based inventions. The data was collected from the conceptualization of telacebec (2010) QcrB to December 2022. A little interesting and encouraging research has been performed on QcrB inhibitors. Telacebec and TB47 are established QcrB inhibitors in the clinical trial. The inventive QcrB inhibitor-based drug combinations can potentially handle DRTB and reduce the TB therapy duration. The authors anticipate great opportunities in fostering QcrB inhibitor-based patentable pharmaceutical inventions against TB. Drug repurposing can be a promising strategy to get safe and effective QcrB inhibitors. However, developing drug resistance, drug tolerance, and selectivity of QcrB inhibitors for Mtb will be the main challenges in developing effective QcrB inhibitors. In conclusion, QcrB is a promising drug target for developing effective treatments for active, latent, and drug-resistant TB. Many inventive and patentable combinations and compositions of QcrB inhibitors with other anti-TB drugs are anticipated as future treatments for TB.

Symptom Profile of Patients With Post-COVID-19 Conditions and Influencing Factors for Recovery

Background

The aim of the study was to examine the factors that influence the improvement of post-coronavirus disease 2019 (COVID-19) symptoms.

Methods

We investigated the biomarkers and post-COVID-19 symptoms status of 120 post-COVID-19 symptomatic outpatients (44 males and 76 females) visiting our hospital. This study was a retrospective analysis, so we analyzed the course of symptoms only for those who could follow the progress of the symptoms for 12 weeks. We analyzed the data including the intake of zinc acetate hydrate.

Results

The main symptoms that remained after 12 weeks were, in descending order: taste disorder, olfactory disorder, hair loss, and fatigue. Fatigue was improved in all cases treated with zinc acetate hydrate 8 weeks later, exhibiting a significant difference from the untreated group (P = 0.030). The similar trend was observed even 12 weeks later, although there was no significant difference (P = 0.060). With respect to hair loss, the group treated with zinc acetate hydrate showed significant improvements 4, 8, and 12 weeks later, compared with the untreated group (P = 0.002, P = 0.002, and P = 0.006).

Conclusion

Zinc acetate hydrate may improve fatigue and hair loss as symptoms after contracting COVID-19.

Oral Brincidofovir Therapy for Monkeypox Outbreak: A Focused Review on the Therapeutic Potential, Clinical Studies, Patent Literature, and Prospects

The monkeypox disease (MPX) outbreak of 2022 has been reported in more than one hundred countries and is becoming a global concern. Unfortunately, only a few treatments, such as tecovirimat (TCV), are available against MPX. Brincidofovir (BCV) is a United States Food and Drug Administration (USFDA)-approved antiviral against smallpox. This article reviews the potential of BCV for treating MPX and other Orthopoxvirus (OPXVs) diseases. The literature for this review was collected from PubMed, authentic websites (USFDA, Chimerix), and freely available patent databases (USPTO, Espacenet, and Patentscope). BCV (a lipophilic derivative of cidofovir) has been discovered and developed by Chimerix Incorporation, USA. Besides smallpox, BCV has also been tested clinically for various viral infections (adenovirus, cytomegalovirus, ebola virus, herpes simplex virus, and double-stranded DNA virus). Many health agencies and reports have recommended using BCV for MPX. However, no health agency has yet approved BCV for MPX. Accordingly, the off-label use of BCV is anticipated for MPX and various viral diseases. The patent literature revealed some important antiviral compositions of BCV. The authors believe there is a huge opportunity to create novel, inventive, and patentable BCV-based antiviral therapies (new combinations with existing antivirals) for OPXVs illnesses (MPX, smallpox, cowpox, camelpox, and vaccinia). It is also advised to conduct drug interaction (food, drug, and disease interaction) and drug resistance investigations on BCV while developing its combinations with other medications. The BCV-based drug repurposing options are also open for further exploration. BCV offers a promising opportunity for biosecurity against OPXV-based bioterrorism attacks and to control the MPX outbreak of 2022.

MmpL3 Inhibition as a Promising Approach to Develop Novel Therapies against Tuberculosis: A Spotlight on SQ109, Clinical Studies, and Patents Literature

Tuberculosis (TB) is accountable for considerable global morbidity and mortality. Effective TB therapy with multiple drugs completes in about six months. The longer duration of TB therapy challenges patient compliance and contributes to treatment collapse and drug resistance (DR) progress. Therefore, new medications with an innovative mechanism of action are desperately required to shorten the TB therapy's duration and effective TB control. The mycobacterial membrane protein Large 3 (MmpL3) is a novel, mycobacteria-conserved and recognized promiscuous drug target used in the development of better treatments for multi-drug resistance TB (MDR-TB) and extensively drug-resistant TB (XDR-TB). This article spotlights MmpL3, the clinical studies of its inhibitor (SQ109), and the patent literature. The literature on MmpL3 inhibitors was searched on PubMed and freely available patent databases (Espacenet, USPTO, and PatentScope). SQ109, an analog of ethambutol (EMB), is an established MmpL3 inhibitor and has completed Phase 2b-3 clinical trials. Infectex and Sequella are developing orally active SQ109 in partnership to treat MDR pulmonary TB. SQ109 has demonstrated activity against drug-sensitive (DS) and drug-resistant (DR) Mycobacterium tuberculosis (Mtb) and a synergistic effect with isoniazid (INH), rifampicin (RIF), clofazimine (CFZ), and bedaquiline (BNQ). The combination of SQ109, clofazimine, bedaquiline, and pyrazinamide (PZA) has been patented due to its excellent anti-TB activity against MDR-TB, XDR-TB, and latent-TB. The combinations of SQ109 with other anti-TB drugs (chloroquine, hydroxychloroquine, and sutezolid) have also been claimed in the patent literature. SQ109 is more potent than EMB and could substitute EMB in the intensive stage of TB treatment with the three- or four-drug combination. Developing MmpL3 inhibitors is a promising approach to fighting the challenges associated with DS-TB and DR-TB. The authors foresee MmpL3 inhibitors such as SQ109 as future drugs for TB treatment.

Selenium and COVID-19: A spotlight on the clinical trials, inventive compositions, and patent literature

Selenium is an indispensable trace element for all living organisms. It is an essential structural component of several selenium-dependent enzymes, which support the human body's defense mechanism. Recently, the significance of selenium in preventing/treating COVID-19 has been documented in the literature. This review highlights the clinical studies, compositions, and patent literature on selenium to prevent/treat COVID-19. Selenium exerts its anti-COVID-19 action by reducing oxidative stress, declining the expression of the ACE-2 receptor, lowering the discharge of pro-inflammatory substances, and inhibiting the 3CLPro (main protease) and PLpro enzyme of SARS-CoV-2. The data of clinical studies, inventive compositions, and patent literature revealed that selenium monotherapy and its compositions with other nutritional supplements/drugs (vitamin, iron, zinc, copper, ferulic acid, resveratrol, spirulina, N-acetylcysteine, fish oil, many herbs, doxycycline, azithromycin, curcumin, quercetin, etc.,) might be practical to prevent/treat COVID-19. The studies have also suggested a correlation between COVID-19 and selenium deficiency. This indicates that adequate selenium supplementation may provide promising treatment outcomes in COVID-19 patients. The authors foresee the development and commercialization of Selenium-based compositions and dosage forms (spray, inhalers, control release dosage forms, etc.) to battle COVID-19. We also trust that numerous selenium-based compositions are yet to be explored. Accordingly, there is good scope for scientists to work on developing novel and inventive selenium-based compositions to fight against COVID-19. However, there is also a need to consider the narrow therapeutic window and chemical interaction of selenium before developing selenium-based compositions.

Antioxidant, Anti-inflammatory, and Immunomodulatory Roles of Nonvitamin Antioxidants in Anti-SARS-CoV-2 Therapy

Viral pathologies encompass activation of pro-oxidative pathways and inflammatory burst. Alleviating overproduction of reactive oxygen species and cytokine storm in COVID-19 is essential to counteract the immunogenic damage in endothelium and alveolar membranes. Antioxidants alleviate oxidative stress, cytokine storm, hyperinflammation, and diminish the risk of organ failure. Direct antiviral roles imply: impact on viral spike protein, interference with the ACE2 receptor, inhibition of dipeptidyl peptidase 4, transmembrane protease serine 2 or furin, and impact on of helicase, papain-like protease, 3-chyomotrypsin like protease, and RNA-dependent RNA polymerase. Prooxidative environment favors conformational changes in the receptor binding domain, promoting the affinity of the spike protein for the host receptor. Viral pathologies imply a vicious cycle, oxidative stress promoting inflammatory responses, and vice versa. The same was noticed with respect to the relationship antioxidant impairment-viral replication. Timing, dosage, pro-oxidative activities, mutual influences, and interference with other antioxidants should be carefully regarded. Deficiency is linked to illness severity.

A Glance at the Development and Patent Literature of Tecovirimat: The First-in-Class Therapy for Emerging Monkeypox Outbreak

Monkeypox disease (MPX) is currently considered a global threat after COVID-19. European Medicines Agency (EMA) approved Tecovirimat in capsule dosage form (200 mg) as the first treatment for MPX in January 2022. This article highlights Tecovirimat’s development and patent literature review and is believed to benefit the scientists working on developing MPX treatments. The literature for Tecovirimat was gathered from the website of SIGA Technologies (developer of Tecovirimat), regulatory agencies (EMA, United States Food and Drug Administration (USFDA), and Health Canada), PubMed, and freely accessible clinical/patent databases. Tecovirimat was first recognized as an anti-orthopoxvirus molecule in 2002 and developed by SIGA Technologies. The USFDA and Health Canada have also recently approved Tecovirimat to treat smallpox in 2018 and 2021, respectively. The efficacy of Tecovirimat was verified in infected non-human primates (monkeys) and rabbits under the USFDA’s Animal Rule. Most clinical studies have been done on Tecovirimat’s safety and pharmacokinetic parameters. The patent literature has revealed inventions related to the capsule, injection, suspension, crystalline forms, amorphous form, and drug combinations (Tecovirimat + cidofovir) and process for preparing Tecovirimat. The authors foresee the off-label use of Tecovirimat in the USA and Canada for MPX and other orthopoxvirus infections. The authors also trust that there is immense scope for developing new Tecovirimat-based treatments (new drug combinations with other antivirals) for orthopoxvirus and other viral diseases. Drug interaction studies and drug resistance studies on Tecovirimat are also recommended. Tecovirimat is believed to handle the current MPX outbreak and is a new hope of biosecurity against smallpox or orthopoxvirus-related bioterrorism attack.

Nanoscale Technologies in the Fight against COVID-19: From Innovative Nanomaterials to Computer-Aided Discovery of Potential Antiviral Plant-Derived Drugs

The last few years have increasingly emphasized the need to develop new active antiviral products obtained from artificial synthesis processes using nanomaterials, but also derived from natural matrices. At the same time, advanced computational approaches have found themselves fundamental in the repurposing of active therapeutics or for reducing the very long developing phases of new drugs discovery, which represents a real limitation, especially in the case of pandemics. The first part of the review is focused on the most innovative nanomaterials promising both in the field of therapeutic agents, as well as measures to control virus spread (i.e., innovative antiviral textiles). The second part of the review aims to show how computer-aided technologies can allow us to identify, in a rapid and therefore constantly updated way, plant-derived molecules (i.e., those included in terpenoids) potentially able to efficiently interact with SARS-CoV-2 cell penetration pathways.