Melatonin in the Prophylaxis of SARS-CoV-2 Infection in Healthcare Workers (MeCOVID): A Randomised Clinical Trial

Clinical research and drug regulation in the challenging times of individualized therapies: A pivotal role of clinical pharmacology

Since the 1980s, medical specialists in Clinical Pharmacology have been playing a crucial role in the development of drug regulation in Spain. In this article we report on the activities carried out and the prospects for development in three very relevant areas from the regulatory perspective: 1) the development of stable public infrastructures to facilitate non-commercial clinical research with medicines, 2) the regulatory aspects of individual access to medicines in special situations, beyond their regular access after marketing approval and funding by the National Health System, and 3) the challenges of development and access to advanced therapies, with special reference to the figure of the hospital exemption.

Assessing the antiviral potential of melatonin: A comprehensive systematic review

This review assesses the antiviral potential of melatonin through comprehensive analysis of studies across human subjects, animal models, cell cultures, and in-silico simulations. The search strategy targeted relevant research until 22 June 2023, resulting in 20 primary studies after screening and deduplication. The findings highlight strong evidence supporting antiviral properties of melatonin. In silico studies identify melatonin as a candidate against SARS-CoV-2, reducing cytokine storm-related respiratory responses. Cell culture experiments reveal its multifaceted effects on different viruses including respiratory syncytial virus, anti-dengue virus, transmissible gastroenteritis virus, and encephalomyocarditis virus. Animal studies show melatonin reduces mortality and viral replication in various infections such as Venezuelan equine encephalomyelitis and COVID-19. Clinical trials show how it could be evaluated, but with no conclusive evidence of efficacy and safety so far from large, double-blind placebo-controlled trials. These insights showcase the potential of melatonin as a versatile antiviral agent with immunomodulatory, antioxidant, anti-inflammatory and antiviral properties. In summary, our review highlights melatonin's promising antiviral properties across diverse settings. Melatonin's immunomodulatory and antiviral potential makes it a compelling candidate for further investigation, emphasising the need for rigorous clinical trials to establish its safety and efficacy against viral infections.

Development of indolealkylamine derivatives as potential multi-target agents for COVID-19 treatment

COVID-19 is a complex disease with short-term and long-term respiratory, inflammatory and neurological symptoms that are triggered by the infection with SARS-CoV-2. As many drugs targeting single targets showed only limited effectiveness against COVID-19, here, we aimed to explore a multi-target strategy. We synthesized a focused compound library based on C2-substituted indolealkylamines (tryptamines and 5-hydroxytryptamines) with activity for three potential COVID-19-related proteins, namely melatonin receptors, calmodulin and human angiotensin converting enzyme 2 (hACE2). Two molecules from the library, 5e and h, exhibit affinities in the high nanomolar range for melatonin receptors, inhibit the calmodulin-dependent calmodulin kinase II activity and the interaction of the SARS-CoV-2 Spike protein with hACE2 at micromolar concentrations. Both compounds inhibit SARS-CoV-2 entry into host cells and 5h decreases SARS-CoV-2 replication and M^Pro enzyme activity in addition. In conclusion, we provide a proof-of-concept for the successful design of multi-target compounds based on the tryptamine scaffold. Optimization of these preliminary hit compounds could potentially provide drug candidates to treat COVID-19 and other coronavirus diseases.

The circadian rhythm of viruses and its implications on susceptibility to infection

INTRODUCTION

Circadian genes have an impact on multiple hormonal, metabolic, and immunological pathways and have recently been implicated in some infectious diseases.

AREAS COVERED

We review aspects related to the current knowledge about circadian rhythm and viral infections, their consequences, and the potential therapeutic options.

EXPERT OPINION

Expert opinion: In order to address a problem, it is necessary to know the topic in depth. Although in recent years there has been a growing interest in the role of circadian rhythms, many relevant questions remain to be resolved. Thus, the mechanisms linking the circadian machinery against viral infections are poorly understood. In a clear approach to personalized precision medicine, in order to treat a disease in the most appropriate phase of the circadian rhythm, and in order to achieve the optimal efficacy, it is highly recommended to carry out studies that improve the knowledge about the circadian rhythm.