1. INTRODUCTION
Coronavirus is a member of the Coronaviridae family, a coated RNA virus,
causing a common pathogenesis between humans and animals [1]. The
coronavirus family can cause different forms of disease varying from
simple cold and gastrointestinal symptoms to pneumonia and bronchitis or
acute respiratory distress syndrome (ARDS) [2-7].
Severe Acute Respiratory Syndrome-related Coronavirus (SARS-CoV) and
Middle East Respiratory Syndrome-related Coronavirus (MERS-CoV) were
some of the most important epidemics caused by coronaviruses in the form
of severe pneumonia leading to ARDS [2, 8, 9]. COVID-19, in
compression with other coronaviruses, has been reported to have a high
prevalence and rapid transmission ability which caused the current
pandemic in a very short time [10].
COVID-19 causes asymptomatic and symptomatic infections; symptomatic
patients may present with broad manifestations from dry cough, sore
throat, fever, myalgia, and shortness of breath to respiratory failure
leading to intubation and mechanical ventilation [11]. In severe
cases of COVID-19 infection, progression to sepsis and multiple organ
failure has been reported [12-16]. The pathogenesis of COVID-19
infection combines primary viraemia and secondary inflammation resulting
from cytokine storm; in patients with lung involvement this can lead to
inflammation and destruction of the alveoli. Therefore, prevention of
cytokine storm seems to be rational in the treatment of moderate to
severe COVID-19 infection. Some medications such as hydroxychloroquine
(HCQ) with anti-inflammatory properties and antiviral medications like
lopinavir/ ritonavir have been reported to be effective in the treatment
of SARS-CoV-2 [17-19]. Pentoxifylline is a well-known medication
with anti-inflammatory properties, prescribing in the treatment of many
clinical conditions [14, 19].
The anti-inflammatory effects of Pentoxifylline (PTX) include decreasing
in the production of proinflammatory cytokines and inflammatory
parameters such as TNF and IFN-gamma IL-6, and IL-1 which help suppress
the inflammation [20, 21]. Moreover, PTX enhances the blood flow
within narrow arteries, resulting in better circulation and oxygenation
[22]. In the current study, the efficacy and safety of PTX in the
treatment and recovery of patients with moderate to severe COVID-19
infection was investigated in a randomized controlled clinical trial.