COVID-19 outcomes among hospitalized men with or without exposure to alpha-1-adrenergic receptor blocking agents (preprint)

Importance: Alpha-1-adrenergic receptor antagonists (1-blockers) can abrogate pro-inflammatory cytokines and may improve outcomes among patients with respiratory infections. Repurposing readily available drugs such as 1-blockers could augment the medical response to the COVID-19 pandemic. Objective: To evaluate the association between 1-blocker exposure and COVID-19 mortality Design: Real-world evidence study Setting: Patient level data with 32,355 records tested for SARS-CoV-2 at the Mount Sinai Health System including 8,442 laboratory-confirmed cases extracted from five member hospitals in the New York City metropolitan area. Participants: 2,627 men aged 45 or older admitted with COVID-19 between February 24 and May 31, 2020 Exposures: 1-blocker use as an outpatient or while admitted for COVID-19 Main Outcomes and Measures: In-hospital mortality Results: Men exposed to 1-blockers (N=436) were older (median age 73 vs. 64 years, P<0.001) and more likely to have comorbidities than unexposed men (N=2,191). Overall, 758 (28.9%) patients died in hospital, 1,589 (60.5%) were discharged, and 280 (10.7%) were still hospitalized as of May 31, 2020. Outpatient exposure to 1-blockers was not associated with COVID-19 hospital outcomes, though there was a trend towards significance (OR 0.749, 95% CI 0.527-1.064; P=0.106). Conversely, inpatient use of 1-blockers was independently associated with improved in-hospital mortality in both multivariable logistic (OR 0.633, 95% CI 0.434-0.921; P=0.017) and Cox regression analyses (HR 0.721, 95% CI 0.572-0.908; P=0.006) adjusting for patient demographics, comorbidities, and baseline vitals and labs. Age-stratified analyses suggested greater benefit from inpatient 1-blocker use among younger age groups: Age 45-65 OR 0.384, 95% CI 0.164-0.896 (P=0.027); Age 55-75 OR 0.511, 95% CI 0.297-0.880 (P=0.015); Age 65-89 OR 0.810, 95% CI 0.509-1.289 (P=0.374). Conclusions and Relevance: Inpatient 1-blocker use was independently associated with improved COVID-19 mortality among hospitalized men. Clinical trials to assess the therapeutic value of 1-blockers in COVID-19 are warranted.

Alpha-1 adrenergic receptor antagonists to prevent hyperinflammation and death from lower respiratory tract infection (preprint)

In severe viral pneumonia, including Coronavirus disease 2019 (COVID-19), the viral replication phase is often followed by hyperinflammation, which can lead to acute respiratory distress syndrome, multi-organ failure, and death. We previously demonstrated that alpha-1 adrenergic receptor ($\alpha_1$-AR) antagonists can prevent hyperinflammation (cytokine storm syndrome) in mice. Here, we conducted retrospective analyses in two cohorts of patients with acute respiratory distress (ARD, n=18,547) and three cohorts with pneumonia (n=400,907). Federated across two ARD cohorts, we find that patients exposed to $\alpha_1$-AR antagonists, as compared to unexposed patients, had a 34% relative risk reduction for mechanical ventilation and death (OR=0.70, p=0.021). We replicated these methods on three pneumonia cohorts, all with similar effects on both outcomes. All results were robust to sensitivity analyses. These results highlight the urgent need for prospective trials testing whether prophylactic use of $\alpha_1$-AR antagonists ameliorates lower respiratory tract infection-associated cytokine storm syndrome, as observed in COVID-19.

Targeting the catecholamine-cytokine axis to prevent SARS-CoV-2 cytokine storm syndrome (preprint)

The mortality of Coronavirus disease 2019 (COVID-19) appears to be driven by acute respiratory distress syndrome (ARDS) and a dysregulated immune response to SARS-CoV-2. Emerging evidence suggests that a subset of COVID-19 is characterized by the development of a cytokine storm syndrome (CSS), and interleukin (IL)-6 levels are predictors of COVID-19 severity and in-hospital mortality. Targeting hyper-inflammation in COVID-19 may be critical for reducing mortality. Catecholamines enhance inflammatory injury by augmenting the production of IL-6 and other cytokines through a self-amplifying feed-forward loop in immune cells that requires alpha-1 adrenergic receptor (1-AR) signaling. Prophylactic inhibition of catecholamine synthesis with the 1-AR antagonist prazosin reduced catecholamines and cytokine responses in mice, and resulted in markedly increased survival following various hyper-inflammatory stimuli. These findings offer a rationale for studying 1-AR antagonists in the prophylaxis of patients with COVID-19-CSS and ARDS. As high infection rates threaten to overwhelm hospital capacity during this pandemic, preventative approaches that ameliorate COVID-19 severity and reduce excessive mortality are desperately needed. We hypothesize that treatment with prazosin of individuals who test positive for SARS-CoV-2 could reduce catecholamine surges, secondary cytokine dysregulation, and mortality. To investigate a potential role for 1-AR antagonists in preventing poor outcomes in ARDS, we conducted a retrospective analysis of hospitalized patients diagnosed with ARDS. Using data from the Truven Health MarketScan Research Database (2010-2017), we identified 13,125 men (age 45-64) with ARDS, of whom 655 patients (5.0%) were prescribed 1-AR antagonists in the previous year. Applying logistic regression models, we found that patients with prior use of 1-AR antagonists had lower odds of invasive mechanical ventilation compared to non-users (adjusted OR=0.75, 95% CI 0.59-0.95, p=0.019). Perhaps more importantly, those patients had a ~36% lower incidence of both being ventilated and dying in the hospital (adjusted OR=0.59, 95% CI 0.34-0.95, p=0.042). By contrast, prior use of beta-adrenergic receptor ({beta}-AR) antagonists was not correlated with either outcome. We extended these analyses to patients admitted with pneumonia. Of 108,956 subjects in this cohort, 5,498 patients (5.0%) were taking 1-AR antagonist. Similar to ARDS, patients with pneumonia on 1-AR antagonists (but no {beta}-AR antagonists) had a lower odds of mechanical ventilation (adjusted OR=0.83, 95% CI 0.75-0.92, p<0.001) and of both being ventilated and dying in the hospital (adjusted OR=0.77, 95% CI 0.62-0.94, p=0.014) compared to non-users. Mirroring findings from pre-clinical models, these data support a clinical rationale to study 1-AR antagonists in the prevention of severe complications of pneumonia, ARDS, and COVID-19. Prospective, randomized clinical trials of alpha-1 receptor antagonists (e.g. prazosin) administered prior to the onset of severe symptoms are needed to assess their efficacy in preventing CSS and reducing mortality in COVID-19.