Association and pharmacological synergism of the triple drug therapy baricitinib/remdesivir/rhACE2 for the management of COVID-19 infection

Atopic dermatitis: treatment and innovations in immunotherapy

Atopic dermatitis (AD) is a common inflammatory skin disease characterized by itching and skin barrier dysfunction. Moderate to severe AD is often refractory to first-line topical treatments, and systemic immunosuppressants have been shown to be effective but have significant adverse effects. The paucity of basic treatments has contributed to the development of targeted topical and systemic immunotherapies based on the use of small molecules and biologic drugs which can directly interact with AD pathogenetic pathways. They represent a new era of therapeutic innovation. Additional new treatments are desirable since AD is a heterogeneous disease marked by different immunological phenotypes. This manuscript will review the mechanism of action, safety profile, and efficacy of promising new systemic immunological treatments for AD. Since moderate to severe AD can result in poor quality of life, the development of targeted and well-tolerated immunomodulators is a crucial purpose. The introduction of new pharmacological agents may offer new therapeutic options. However, there is the need to evaluate how "narrow-acting" agents, such as individual interleukin inhibitors, will perform under the safety and efficacy profiles compared with "broad-acting" agents, such as JAK inhibitors.

Comparing Molnupiravir to Nirmatrelvir/Ritonavir (Paxlovid) in the Treatment of Mild-to-Moderate COVID-19 in Immunocompromised Cancer Patients

BACKGROUND

Nirmatrelvir/Ritonavir has been shown to reduce the risk of COVID-19 progression by 88% compared to placebo, while Molnupiravir reduced it by 31%. However, these two agents have not been compared head-to-head. We therefore compared the safety and efficacy of both agents for the treatment of mild-to-moderate COVID-19 in immunocompromised cancer patients.

METHODS

We identified 240 cancer patients diagnosed with COVID-19 and treated with Molnupiravir or Nirmatrelvir/Ritonavir. Patients were matched using a 1:2 ratio based on age group (18-64 years vs. ≥65) and type of cancer. The collected data included demographics, comorbidities, and treatment outcome.

RESULTS

Both groups had comparable characteristics and presenting symptoms. However, dyspnea was more prevalent in the Molnupiravir group, while sore throat was more prevalent in the Nirmatrelvir/Ritonavir group. The rate of disease progression was comparable in both groups by univariate and multivariable analysis. Treatment with Molnupiravir versus Nirmatrelvir/Ritonavir revealed no significant difference in disease progression by multivariable analysis (adjusted OR = 1.31, 95% CI: 0.56-3.14, p = 0.70). Patients who received Nirmatrelvir/Ritonavir, however, were significantly more prone to having drug-drug interactions/adverse events (30% vs. 0%, p < 0.0001).

CONCLUSIONS

In the treatment of mild-to-moderate COVID-19 in cancer patients, Molnupiravir was comparable to Nirmatrelvir/Ritonavir in preventing progression to severe disease/death and rebound events, and it had a superior safety profile.

Inhibition of SARS-CoV-2 3CL protease by the anti-viral chimeric protein RetroMAD1

COVID-19 results from SARS-CoV-2, which mutates frequently, challenging current treatments. Therefore, it is critical to develop new therapeutic drugs against this disease. This study explores the interaction between SARS-CoV-2 3CLpro and RetroMAD1, a well-characterized coronavirus protein and potential drug target, using in-silico methods. The analysis through the HDOCK server showed stable complex formation with a binding energy of -12.3, the lowest among reference drugs. The RetroMAD1-3CLpro complex underwent a 100 ns molecular dynamics simulation (MDS) in an explicit solvation system, generating various trajectories, including RMSD, RMSF, hydrogen bonding, radius of gyration, and ligand binding energy. MDS results confirmed intact interactions within the RetroMAD1-3CLpro complex during simulations. In vitro experiments validated RetroMAD1's ability to inhibit 3CLpro enzyme activity and prevent SARS-CoV-2 infection in human bronchial cells. RetroMAD1 exhibited antiviral efficacy comparable to Remdesivir without cytotoxicity at effective concentrations. These results suggest RetroMAD1 as a potential drug candidate against SARS-CoV-2, warranting further in vivo and clinical studies to assess its efficiency.

A population pharmacokinetic model of remdesivir and its major metabolites based on published mean values from healthy subjects

Remdesivir is a direct-acting anti-viral agent. It was originally evaluated against filoviruses. However, during the COVID-19 pandemic, it was investigated due to its anti-viral activities against (SARS-CoV-2) virus. Therefore remdesivir received conditional approval for treatment of patients with severe coronavirus disease. Yet, its pharmacokinetic properties are inadequately understood. This report describes the population pharmacokinetics of remdesivir and its two plasma-detectable metabolites (GS-704277 and GS-441524) in healthy volunteers. The data was extracted from published phase I single escalating and multiple i.v remdesivir dose studies conducted by the manufacturer. The model was developed by standard methods using non-linear mixed effect modeling. Also, a series of simulations were carried out to test suggested clinical doses. The model describes the distribution of remdesivir and each of its metabolites by respective two compartments with sequential metabolism between moieties, and elimination from central compartments. As individual data were not available, only inter-cohort variability could be assessed. The estimated point estimates for central (and peripheral) volumes of distribution for remdesivir, GS-704277, and GS-441524 were 4.89 L (46.5 L), 96.4 L (8.64 L), and 26.2 L (66.2 L), respectively. The estimated elimination clearances of remdesivir, GS704277, and GS-441524 reached 18.1 L/h, 36.9 L/h, and 4.74 L/h, respectively. The developed model described the data well. Simulations of clinically approved doses showed that GS-441524 concentrations in plasma exceeded the reported EC₅₀ values during the complete duration of treatment. Nonetheless, further studies are needed to explore the pharmacokinetics of remdesivir and its relationship to clinical efficacy, and the present model may serve as a useful starting point for additional evaluations.

Comparative evaluation of authorized drugs for treating Covid-19 patients

Background and Aims

Vaccines are the first line of defense against coronavirus disease 2019 (Covid-19). However, the antiviral drugs provide a new tool to fight the Covid-19 pandemic. Here we aimed for a comparative evaluation of authorized drugs for treating Covid-19 patients.

Methods

We searched in PubMed and Google Scholar using keywords and terms such as Covid, SARS-CoV-2, Coronavirus disease 2019, therapeutic management, hospitalized Covid-19 patients, Covid-19 treatment. We also gathered information from reputed newspapers, web portals, and websites. We thoroughly observed, screened, and included the studies relevant to our inclusion criteria. We included only the United States Food and Drug Administration (FDA) authorized drugs for this review.

Results

We found that molnupiravir and paxlovid are available for oral use, and remdesivir is for only hospitalized patients. Paxlovid is a combination of nirmatrelvir and ritonavir, nirmatrelvir is a protease inhibitor (ritonavir increases the concentration of nirmatrelvir), and the other two (remdesivir and molnupiravir) are nucleoside analog prodrugs. Remdesivir and molnupiravir doses do not need to adjust in renal and hepatic impairment. However, the paxlovid dose adjustment is required for mild to moderate renal or hepatic impaired patients. Also, the drug is not allowed for Covid-19 patients with severe renal or hepatic impairment. Preliminary studies showed oral antiviral drugs significantly reduce hospitalization or death among mild to severe patients. Moreover, the US FDA has approved four monoclonal antibodies for Covid-19 treatment. Studies suggest that these drugs would reduce the risk of hospitalization or severity of symptoms. World Health Organization strongly recommended the use of corticosteroids along with other antiviral drugs for severe or critically hospitalized patients.

Conclusion

All authorized drugs are effective in inhibiting viral replication for most SARS-CoV-2 variants. Therefore, along with vaccines, these drugs might potentially aid in fighting the Covid-19 pandemic.

Pharmacotherapy Based on ACE2 Targeting and COVID-19 Infection

The new SARS-CoV-2 coronavirus is responsible for the COVID-19 pandemic. A massive vaccination campaign, which is still ongoing, has averted most serious consequences worldwide; however, lines of research are continuing to identify the best drug therapies to treat COVID-19 infection. SARS-CoV-2 penetrates the cells of the host organism through ACE2. The ACE2 protein plays a key role in the renin–angiotensin system (RAS) and undergoes changes in expression during different stages of COVID-19 infection. It appears that an unregulated RAS is responsible for the severe lung damage that occurs in some cases of COVID-19. Pharmacologically modifying the expression of ACE2 could be an interesting line of research to follow in order to avoid the severe complications of COVID-19.

The role of angiotensin-converting enzyme 2 (ACE2) genetic variations in COVID-19 infection: a literature review

Background

The angiotensin-converting enzyme-2 (ACE2) is recognized to be the fundamental receptor of severe acute respiratory syndrome coronavirus-2 (SARS-CoV2), responsible for the worldwide Coronavirus Disease-2019 (COVID-19) epidemic. However, genetic differences between people besides racial considerations and their relation to disease susceptibility are still not fully elucidated.

Main body

To uncover the role of ACE2 in COVID-19 infection, we reviewed the published studies that explore the association of COVID-19 with the functional characteristics of ACE2 and its genetic variations. Notably, emerging studies tried to determine whether the ACE2 variants and/or expression could be associated with SARS-CoV/SARS-CoV2 have conflicting results. Some researchers investigated the potential of "population-specific" ACE2 genetic variations to impact the SARS-CoV2 vulnerability and suggested no ethnicity enrichment for ACE2 polymorphisms that could influence SARS-CoV2 S-protein binding. At the same time, some studies use data mining to predict several ACE2 variants that could enhance or decline susceptibility to SARS-CoV. On the other hand, fewer studies revealed an association of ACE2 expression with COVID-19 outcome reporting higher expression levels of ACE2 in East Asians.

Conclusions

ACE2 gene variants and expression may modify the deleterious consequences of SARS-CoV2 to the host cells. It is worth noting that apart from the differences in gene expression and the genetic variations of ACE2, many other environmental and/or genetic factors could modify the disease outcome, including the genes for the innate and the adaptive immune response.

A Unique Robust Dual-Promoter-Driven and Dual-Reporter-Expressing SARS-CoV-2 Replicon: Construction and Characterization

The severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2, SARS2) remains a great global health threat and demands identification of more effective and SARS2-targeted antiviral drugs, even with successful development of anti-SARS2 vaccines. Viral replicons have proven to be a rapid, safe, and readily scalable platform for high-throughput screening, identification, and evaluation of antiviral drugs against positive-stranded RNA viruses. In the study, we report a unique robust HIV long terminal repeat (LTR)/T7 dual-promoter-driven and dual-reporter firefly luciferase (fLuc) and green fluorescent protein (GFP)-expressing SARS2 replicon. The genomic organization of the replicon was designed with quite a few features that were to ensure the replication fidelity of the replicon, to maximize the expression of the full-length replicon, and to offer the monitoring flexibility of the replicon replication. We showed the success of the construction of the replicon and expression of reporter genes fLuc and GFP and SARS structural N from the replicon DNA or the RNA that was in vitro transcribed from the replicon DNA. We also showed detection of the negative-stranded genomic RNA (gRNA) and subgenomic RNA (sgRNA) intermediates, a hallmark of replication of positive-stranded RNA viruses from the replicon. Lastly, we showed that expression of the reporter genes, N gene, gRNA, and sgRNA from the replicon was sensitive to inhibition by Remdesivir. Taken together, our results support use of the replicon for identification of anti-SARS2 drugs and development of new anti-SARS strategies targeted at the step of virus replication.