Treatment of COVID-19 pneumonia with low-dose radiotherapy plus standard of care versus standard of care alone in frail patients : The SEOR-GICOR IPACOVID comparative cohort trial

PURPOSE

To assess the efficacy of lung low-dose radiotherapy (LD-RT) in the treatment of patients with COVID-19 pneumonia.

MATERIALS AND METHODS

Ambispective study with two cohorts to compare treatment with standard of care (SoC) plus a single dose of 0.5 Gy to the whole thorax (experimental prospective cohort) with SoC alone (control retrospective cohort) for patients with COVID-19 pneumonia not candidates for admission to the intensive care unit (ICU) for mechanical ventilation.

RESULTS

Fifty patients treated with LD-RT were compared with 50 matched controls. Mean age was 85 years in both groups. An increase in arterial oxygen partial pressure (PaO2)/fraction of inspired oxygen (PAFI) in the experimental LD-RT-treated group compared to the control group could not be found at 48 h after LD-RT, which was the primary endpoint of the study. However, PAFI values significantly improved after 1 month (473 vs. 302 mm Hg; p < 0.0001). Pulse oxymetric saturation/fraction of inspired oxygen (SAFI) values were also significantly higher in LD-RT-treated patients than in control patients at 1 week (405 vs. 334 mm Hg; p = 0.0157) and 1 month after LD-RT (462 vs. 326 mm Hg; p < 0.0001). All other timepoint measurements of the respiratory parameters were similar across groups. Patients in the experimental group were discharged from the hospital significantly earlier (23 vs. 31 days; p = 0.047). Fifteen and 26 patients died due to COVID-19 pneumonia in the experimental and control cohorts, respectively (30% vs. 48%; p = 0.1). LD-RT was associated with a decreased odds ratio (OR) for 1‑month COVID-19 mortality (OR = 0.302 [0.106-0.859]; p = 0.025) when adjusted for potentially confounding factors. Overall survival was significantly prolonged in the LD-RT group compared to the control group (log-rank p = 0.027). No adverse events related to radiation treatment were observed.

CONCLUSION

Treatment of frail patients with COVID-19 pneumonia with SoC plus single-dose LD-RT of 0.5 Gy improved respiratory parameters, reduced the period of hospitalization, decreased the rate of 1‑month mortality, and prolonged actuarial overall survival compared to SoC alone.

SARS-CoV-2 Serum Viral Load and Prognostic Markers Proposal for COVID-19 Pneumonia in Low-Dose Radiation Therapy Treated Patients

Several studies have shown that the plasma RNA of SARS-CoV-2 seems to be associated with a worse prognosis of COVID-19. In the present study, we investigated plasma RNA in COVID-19 patients treated with low-dose radiotherapy to determine its prognostic value. Data were collected from the IPACOVID prospective clinical trial (NCT04380818). The study included 46 patients with COVID-19 pneumonia treated with a whole-lung dose of 0.5 Gy. Clinical follow-up, as well as laboratory variables, and SARS-CoV-2 serum viral load, were analyzed before LDRT, at 24 h, and one week after treatment. The mean age of the patients was 85 years, and none received any of the SARS-CoV-2 vaccine doses. The mortality ratio during the course of treatment was 33%. RT-qPCR showed amplification in 23 patients. Higher mortality rate was associated with detectable viremia. Additionally, C-reactive protein, lactate dehydrogenase, and aspartate aminotransferase were significant risk factors associated with COVID-19 mortality. Our present findings show that detectable SARS-CoV-2 plasma viremia 24 h before LDRT is significantly associated with increased mortality rates post-treatment, thus downsizing the treatment success.

The Paradox of COVID-19 in Sub-Saharan Africa: Why it is More Unethical Not to Investigate Low Dose Radiotherapy for COVID-19

An accumulating body of evidence shows that various ethnicities are differentially affected by SARS-COV-2 infection. Moreover, some evidence shows that due to the vaccine inequity and millions of people living with HIV, a major catastrophe could occur in African countries that possibly affects the whole world. Given the possibility that Neanderthal genes confer a slight increase in susceptibility, this difference, at least to some extent, might possibly decrease the risk of the emergence of new SARS-CoV-2 variants among black people in Africa. Recent studies show less death and fewer cases among the ethnic group classified as “Black Africans”. Although Neanderthal DNA might explain some differences in morbidity and mortality of COVID-19, a multitude of confounders complicate things to where drawing definite conclusions is hard or even impossible. Using selective-pressure-free treatments (e.g. low dose radiotherapy) for COVID-19 pneumonia would be of crucial importance everywhere, but particularly in sub-Saharan Africa, where “long COVID” in millions of people with HIV paves the road for the more frequent emergence of new variants.

Impact of X-radiation in the management of COVID-19 disease

Coronaviruses are a diverse group of viruses that infect both animals and humans. Even though the existence of coronavirus and its infection to humans is not new, the 2019-novel coronavirus (nCoV) caused a major burden to individuals and society i.e., anxiety, fear of infection, extreme competition for hospitalization, and more importantly financial liability. The nCoV infection/disease diagnosis was based on non-specific signs and symptoms, biochemical parameters, detection of the virus using reverse-transcription polymerase chain reaction (RT-PCR), and X-ray-based imaging. This review focuses on the consolidation of potentials of X-ray-based imaging modality [chest-X radiography (CXR) and chest computed tomography (CT)] and low-dose radiation therapy (LDRT) for screening, severity, and management of COVID-19 disease. Reported studies suggest that CXR contributed significantly toward initial rapid screening/diagnosis and CT- imaging to monitor the disease severity. The chest CT has high sensitivity up to 98% and low specificity for diagnosis and severity of COVID-19 disease compared to RT-PCR. Similarly, LDRT compliments drug therapy in the early recovery/Less hospital stays by maintaining the physiological parameters better than the drug therapy alone. All the results undoubtedly demonstrated the evidence that X-ray-based technology continues to evolve and play a significant role in human health care even during the pandemic.

Effect of Low-Dose Radiotherapy on the Circulating Levels of Paraoxonase-1-Related Variables and Markers of Inflammation in Patients with COVID-19 Pneumonia

The aim of our study was to investigate the changes produced by low-dose radiotherapy (LDRT) in the circulating levels of the antioxidant enzyme paraoxonase-1 (PON1) and inflammatory markers in patients with COVID-19 pneumonia treated with LDRT and their interactions with clinical and radiological changes. Data were collected from the IPACOVID prospective clinical trial (NCT04380818). The study included 30 patients treated with a whole-lung dose of 0.5 Gy. Clinical follow-up, as well as PON1-related variables, cytokines, and radiological parameters were analyzed before LDRT, at 24 h, and 1 week after treatment. Twenty-five patients (83.3%) survived 1 week after LDRT. Respiratory function and radiological images improved in survivors. Twenty-four hours after LDRT, PON1 concentration significantly decreased, while transforming growth factor beta 1 (TGF-β1) increased with respect to baseline. One week after LDRT, patients had increased PON1 activities and lower PON1 and TGF-β1 concentrations compared with 24 h after LDRT, PON1 specific activity increased, lactate dehydrogenase (LDH), and C-reactive protein (CRP) decreased, and CD4+ and CD8+ cells increased after one week. Our results highlight the benefit of LDRT in patients with COVID-19 pneumonia and it might be mediated, at least in part, by an increase in serum PON1 activity at one week and an increase in TGF-β1 concentrations at 24 h.

Revisiting the Paradox of Smoking: Radioactivity in Tobacco Smoke or Suppressing the SARS-CoV-2 Receptor, Angiotensin-Converting Enzyme 2, via Aryl-Hydrocarbon Receptor Signal?

Despite current controversies, some reports show a paradoxical mitigating effect associated with smoking in individuals with symptomatic COVID-19 compared to the general population. To explain the potential mechanisms behind the lower number of hospitalized COVID-19 patients, it has been hypothesized that cigarette smoking may reduce the odds of cytokine storm and related severe inflammatory responses through cholinergic-mediated anti-inflammatory mechanisms. Japanese scientists have recently identified a potential mechanism behind the lower numbers of COVID-19 cases amongst smokers compared to non-smokers. However, we believe that this mitigative effect may be due to the relatively high concentration of deposited energy of alpha particles emitted from naturally occurring radionuclides such as Po-210 in cigarette tobacco. Regarding COVID-19, other researchers and our team have previously addressed the anti-inflammatory and immune-modulating effects of low doses of ionizing radiation. MC-simulation using the Geant4 Monte Carlo toolkit shows that the radiation dose absorbed in a spherical cell with a radius of .9 μm for a single 5.5 MeV alpha particle is about 5.1 Gy. This energy deposition may trigger both anti-inflammatory and anti-thrombotic effects which paradoxically lower the risk of hospitalization due to COVID-19 in smokers.