Immunomodulatory agents for COVID-19 treatment: possible mechanism of action and immunopathology features.

The novel coronavirus pandemic has emerged as one of the significant medical-health challenges of the current century. The World Health Organization has named this new virus severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Since the first detection of SARS-CoV-2 in November 2019 in Wuhan, China, physicians, researchers, and others have made it their top priority to find drugs and cures that can effectively treat patients and reduce mortality rates. The symptoms of Coronavirus Disease 2019 (COVID-19) include fever, dry cough, body aches, and anosmia. Various therapeutic compounds have been investigated and applied to mitigate the symptoms in COVID-19 patients and cure the disease. Degenerative virus analyses of the infection incidence and COVID-19 have demonstrated that SARS-CoV-2 penetrates the pulmonary alveoli's endothelial cells through Angiotensin-Converting Enzyme 2 (ACE2) receptors on the membrane, stimulates various signaling pathways and causes excessive secretion of cytokines. The continuous triggering of the innate and acquired immune system, as well as the overproduction of pro-inflammatory factors, cause a severe condition in the COVID-19 patients, which is called "cytokine storm". It can lead to acute respiratory distress syndrome (ARDS) in critical patients. Severe and critical COVID-19 cases demand oxygen therapy and mechanical ventilator support. Various drugs, including immunomodulatory and immunosuppressive agents (e.g., monoclonal antibodies (mAbs) and interleukin antagonists) have been utilized in clinical trials. However, the studies and clinical trials have documented diverging findings, which seem to be due to the differences in these drugs' possible mechanisms of action. These drugs' mechanism of action generally includes suppressing or modulating the immune system, preventing the development of cytokine storm via various signaling pathways, and enhancing the blood vessels' diameter in the lungs. In this review article, multiple medications from different drug families are discussed, and their possible mechanisms of action are also described.

Alirocumab as Add-On to Atorvastatin Versus Other Lipid Treatment Strategies: ODYSSEY OPTIONS I Randomized Trial.

CONTEXT: Despite current standard of care, many patients at high risk of cardiovascular disease (CVD) still have elevated low-density lipoprotein cholesterol (LDL-C) levels. Alirocumab is a fully human monoclonal antibody inhibitor of proprotein convertase subtilisin/kexin type 9. OBJECTIVE: The objective of the study was to compare the LDL-C-lowering efficacy of adding alirocumab vs other common lipid-lowering strategies. DESIGN, PATIENTS, AND INTERVENTIONS: Patients (n = 355) with very high CVD risk and LDL-C levels of 70 mg/dL or greater or high CVD risk and LDL-C of 100 mg/dL or greater on baseline atorvastatin 20 or 40 mg were randomized to one of the following: 1) add-on alirocumab 75 mg every 2 weeks (Q2W) sc; 2) add-on ezetimibe 10 mg/d; 3) double atorvastatin dose; or 4) for atorvastatin 40 mg regimen only, switch to rosuvastatin 40 mg. For patients not achieving protocol-defined LDL-C goals, the alirocumab dose was increased (blinded) at week 12 to 150 mg Q2W. MAIN OUTCOME MEASURE: The primary end point was percentage change in calculated LDL-C from baseline to 24 weeks (intent to treat). RESULTS: Among atorvastatin 20 and 40 mg regimens, respectively, add-on alirocumab reduced LDL-C levels by 44.1% and 54.0% (P < .001 vs all comparators); add-on ezetimibe, 20.5% and 22.6%; doubling of atorvastatin dose, 5.0% and 4.8%; and switching atorvastatin 40 mg to rosuvastatin 40 mg, 21.4%. Most alirocumab-treated patients (87.2% and 84.6%) achieved their LDL-C goals. Most alirocumab-treated patients (86%) maintained their 75-mg Q2W regimen. Treatment-emergent adverse events occurred in 65.4% of alirocumab patients vs 64.4% ezetimibe and 63.8% double atorvastatin/switch to rosuvastatin (data were pooled). CONCLUSIONS: Adding alirocumab to atorvastatin provided significantly greater LDL-C reductions vs adding ezetimibe, doubling atorvastatin dose, or switching to rosuvastatin and enabled greater LDL-C goal achievement.

Statin-induced immunomodulation alters peripheral invariant natural killer T-cell prevalence in hyperlipidemic patients.

PURPOSE: To assess the difference in the prevalence of invariant Natural Killer T (iNKT) lymphocytes between hyperlipidemic and control individuals and to evaluate changes in iNKT cell levels after 6 months lipid lowering therapy. METHODS: A total of 77 hyperlipidemic individuals (54 ± 5 years) were assigned to simvastatin 40 mg or ezetimibe 10 mg daily for 6 months. Fifty individuals with normal cholesterol levels were used as control. iNKT cells were measured by flow cytometry in peripheral blood. RESULTS: Patients with hypercholesterolemia had significantly lower iNKT cell levels (percentage on the lymphocyte population) compared to control group (0.16 ± 0.04% vs 0.39 ± 0.08%, p = 0.03). iNKT cells significantly increased after 6 months treatment with simvastatin (from 0.15 ± 0.04% to 0.28 ± 0.11%, p = 0.03) but not with ezetimibe (from 0.16 ± 0.05% to 0.17 ± 0.06%, p = 0.55). Simvastatin treatment did not alter the activation status of iNKT cells as measured by HLA-DR expression. Changes of iNKT cells were independent from changes in total (r(2) = 0.009, p = 0.76) or LDL cholesterol (r(2) = 0.008, p = 0.78) reached by simvastatin. CONCLUSIONS: Hyperlipidemic patients have reduced numbers of iNKT in peripheral circulation compared to individuals with normal cholesterol levels. Their number is increasing after long term administration of simvastatin 40 mg but not after ezetimibe.