Renin-angiotensin system inhibitors mitigate radiation pneumonitis by activating ACE2-angiotensin-(1-7) axis via NF-κB/MAPK pathway.

Radiation pneumonitis (RP) affects both patients and physicians during radiation therapy for lung cancer. To date, there are no effective drugs for improving the clinical outcomes of RP. The activation of angiotensin-converting enzyme 2 (ACE2) improves experimental acute lung injury caused by severe acute respiratory syndrome coronavirus, acid inhalation, and sepsis. However, the effects and underlying mechanisms of ACE2 in RP remain unclear. Therefore, this study aimed to investigate the effects of angiotensin-converting enzyme inhibitors and angiotensin II receptor blockers on RP and ACE2/angiotensin-(1-7)/Mas receptor pathway activation. We found that radiotherapy decreased the expression of ACE2 and that overexpression of ACE2 alleviated lung injury in an RP mouse model. Moreover, captopril and valsartan restored ACE2 activation; attenuated P38, ERK, and p65 phosphorylation; and effectively mitigated RP in the mouse model. Further systematic retrospective analysis illustrated that the incidence of RP in patients using renin-angiotensin system inhibitors (RASis) was lower than that in patients not using RASis (18.2% vs. 35.8% at 3 months, p = 0.0497). In conclusion, the current findings demonstrate that ACE2 plays a critical role in RP and suggest that RASis may be useful potential therapeutic drugs for RP.

COVID-19 vaccination perception and uptake among cancer patients in Guangzhou, China.

Patients with cancer are considered at high risk of COVID-19 related complications with higher mortality rates than healthy individuals. This study investigated the perception, acceptance, and influencing factors of COVID-19 vaccination among cancer patients in Guangzhou, China. A cross-sectional survey was conducted in Guangzhou, China from August to November 2021 in two tertiary medical centers. Outpatients were recruited through hospital posters to complete a questionnaire including demographics, medical history, knowledge, and attitude toward COVID-19 vaccines and COVID-19 vaccination status. Chi-square tests and multivariable logistic regression were used to analyze predictors for acceptance of COVID-19 vaccination. In total, only 75 out of 343 patients (21.87%) had received at least one dose of COVID-19 vaccine. Twenty-one patients (6.12%) had received a recommendation about COVID-19 vaccination from their physicians. Patients who were recommended by physicians to get vaccinated (aOR = 11.71 95% CI: 2.71-50.66), with a monthly income of more than CNY 5000 (aOR = 3.94, 95% CI: 1.88-8.26) were more likely to have received COVID-19 vaccination. Cancer patients who had been diagnosed for more than one year (aOR = 0.21, 95% CI: 0.09-0.51), had received multiple cancer treatment strategies (aOR = 0.34, 95% CI: 0.16-0.74), worried about the safety of COVID-19 vaccines (aOR = 0.21, 95% CI: 0.11-0.40), were less likely to have received COVID-19 vaccination. COVID-19 vaccination uptake among cancer patients was insufficient. The proportion of cancer patients receiving vaccination recommendations from physicians remains inadequate. Physicians are expected to play an essential role in patients' knowledge of the safety and effectiveness of COVID-19 vaccines.

Oral famotidine versus placebo in non-hospitalised patients with COVID-19: a randomised, double-blind, data-intense, phase 2 clinical trial.

OBJECTIVE: We assessed whether famotidine improved inflammation and symptomatic recovery in outpatients with mild to moderate COVID-19. DESIGN: Randomised, double-blind, placebo-controlled, fully remote, phase 2 clinical trial (NCT04724720) enrolling symptomatic unvaccinated adult outpatients with confirmed COVID-19 between January 2021 and April 2021 from two US centres. Patients self-administered 80 mg famotidine (n=28) or placebo (n=27) orally three times a day for 14 consecutive days. Endpoints were time to (primary) or rate of (secondary) symptom resolution, and resolution of inflammation (exploratory). RESULTS: Of 55 patients in the intention-to-treat group (median age 35 years (IQR: 20); 35 women (64%); 18 African American (33%); 14 Hispanic (26%)), 52 (95%) completed the trial, submitting 1358 electronic symptom surveys. Time to symptom resolution was not statistically improved (p=0.4). Rate of symptom resolution was improved for patients taking famotidine (p<0.0001). Estimated 50% reduction of overall baseline symptom scores were achieved at 8.2 days (95% CI: 7 to 9.8 days) for famotidine and 11.4 days (95% CI: 10.3 to 12.6 days) for placebo treated patients. Differences were independent of patient sex, race or ethnicity. Five self-limiting adverse events occurred (famotidine, n=2 (40%); placebo, n=3 (60%)). On day 7, fewer patients on famotidine had detectable interferon alpha plasma levels (p=0.04). Plasma immunoglobulin type G levels to SARS-CoV-2 nucleocapsid core protein were similar between both arms. CONCLUSIONS: Famotidine was safe and well tolerated in outpatients with mild to moderate COVID-19. Famotidine led to earlier resolution of symptoms and inflammation without reducing anti-SARS-CoV-2 immunity. Additional randomised trials are required.