Impact of the NRF2 activator, stabilised synthetic sulforaphane, on systemic inflammation in COVID19: results from the STAR-COVID19 trial

Introduction: Dysregulated immune responses are implicated in the pathogenesis of severe COVID19 and may be modulated by the transcription factor Nrf2. Hypothesis: Treatment with stabilised, synthetic sulforaphane (S-SFN)-an Nrf2 inducer-improves clinical status in hospitalised patients with suspected COVID19 pneumonia by curbing the inflammatory response. Method(s): Double-blind RCT of S-SFN (300mg, once daily, 14 days;EudraCT 2020-003486-19) in patients hospitalised with confirmed or suspected COVID19, in Dundee, UK. The primary outcome was the 7 point WHO Clinical Status scale at day 15. Blood samples were taken on days 1, 8 and 15 for measurement of 45 serum cytokines using the Olink Target48 panel. Key neutrophil functions were assessed including migration, phagocytosis and bacterial killing. Result(s): 133 participants were randomized (placebo n=68, S-SFN n=65) from Nov 2020 to May 2021. S-SFN treatment did not improve clinical status at day 15 (adjusted OR 0.87 95%CI 0.41-1.83). In serum, Nrf2 target TGFalpha was significantly increased at day 15 in those receiving S-SFN treatment compared with placebo (p=0.004;linear mixed effects model). Other targets implicated in cytokine storm, including IL6, IL1beta and TNFalpha, were unchanged. Patients receiving Tocilizumab (n=20) were excluded from exploratory analyses due to a strong impact upon IL6 levels, leading to significant increases at day 8 across the study population (p=0.015). S-SFN treatment did not significantly affect neutrophil function. Conclusion(s): S-SFN treatment modulated select Nrf2 targets but did not modulate key cytokines. Further analyses to delineate drug activity are ongoing.

Dipeptidyl Peptidase-1 Inhibition in Patients Hospitalized with COVID-19: a Multicentre Randomized Double-Blind Placebo Controlled Trial

Background: Neutrophil serine proteases (NSPs) are involved in the pathogenesis of COVID19 and are increased in severe and fatal infection. We investigated whether treatment with Brensocatib, an inhibitor of dipeptidyl peptidase-1, an enzyme responsible for the activation of NSPs, would improve outcomes in hospitalized patients with COVID19. Method(s): In a randomized, double-blind, placebo-controlled trial, 406 hospitalized patients with COVID19 with at least one risk factor for severe disease were randomized 1:1 to once-daily Brensocatib 25mg (n=192) or placebo (n=214) for 28 days. Primary outcome was the 7-point World Health Organisation Clinical Status scale at day 29. Secondary outcomes included time to clinical improvement, national early warning score, new oxygen and ventilation use, neutrophil elastase activity in blood and mortality. Finding(s): Brensocatib treatment was associated with worse clinical status at day 29 (adjusted odds ratio 0 72, 95%CI 0 57-0 92) compared to placebo. The adjusted hazard ratio (aHR) for time to clinical improvement was 0 87 (95%CI 0 76-1 00) and time to hospital discharge was 0 98 (95%CI 0 84-1 13). During the 28-day follow-up period, 23 (11%) and 29 (15%) patients died in the placebo and Brensocatib treated groups respectively). Oxygen and new ventilation use were greater in the Brensocatib treated patients. Neutrophil elastase activity in blood was significantly reduced in the Brensocatib group from baseline to day 29. Prespecified subgroup analyses of the primary outcome supported the primary results.

Stabilised, synthetic sulforaphane in hospitalized patients with suspected COVID-19 pneumonia: a double-blind, placebo-controlled RCT

Introduction: The transcription factor Nrf2 downregulates key inflammatory cytokines in COVID-19 (IL-6, IL-1b, COX-2 and TNF-a). We investigated the efficacy of S-SFN (stabilised sulforaphane, activator of Nrf2) to improve clinical outcomes in patients hospitalized with suspected COVID-19. Method(s): Randomized, double-blind, placebo-controlled trial, patients hospitalised with suspected or confirmed COVID-19, radiological pneumonia and a CURB65 score of >= 1 were randomized 1:1 to once-daily S-SFN 300mg or placebo for 14 days. The primary outcome was the 7-point WHO Clinical Status (CS) scale at day 15. Key secondary outcomes included time to clinical improvement, national early warning score (NEWS), oxygen and ventilation use, and mortality. Result(s): The trial was terminated due to futility after 133 patients had been enrolled (S-SFN, n=65 and placebo, n=68). 103 had PCR confirmed COVID-19 infection. S-SFN treatment was not associated with improved CS at day 15 (OR 0.87 95%CI (0.41-1.83, p=0.712). There was no difference in time to clinical improvement (HR 1.02 (0.70- 1.49)). S-SFN was not associated with a reduced length of hospital stay (6.2days vs 7.4days (S-SFN)). There were 26 deaths during the 29-day follow-up, 11 (16.2%) and 15 (23.1%) patients died in the placebo and S-SFN treated groups respectively (HR 1.45 (0.67-3.16)). There were no differences between treatment groups with respect to oxygen or ventilation free days. Adverse events were reported in 44.1% of placebo treated and 64.6% of S-SFN treated patients. Conclusion(s): S-SFN treatment did not improve day 15 clinical status in hospitalized patients with suspected or confirmed COVID-19 infection.

Altered neutrophil proteomes in COVID19 patients 29-days post hospital admission are associated with delayed recovery: results from the PREDICT-COVID19 study

Introduction and ObjectivesNeutrophils are increasingly recognised for a role in acute COVID19, contributing to hyperinflammatory responses, immunothrombosis and tissue damage. However, less is known about the cellular changes occurring within neutrophils in acute disease, as well as neutrophil function in patients recovering from COVID19. Mass spectrometry-based proteomics of neutrophils from hospitalised COVID19 patients sampled longitudinally was utilised to characterise these cells in both acute and long COVID19 (i.e. symptoms for ≥4 weeks).MethodsProspective observational study of hospitalised patients with PCR-confirmed SARS-CoV-2 infection (May 2020–December 2020). Patients were enrolled within 96 hours of admission, with longitudinal sampling up to day 29. Control groups comprised hospitalised patients with non-COVID19 acute respiratory infection and age-matched non-infected controls. Neutrophils isolated from peripheral blood were processed for mass spectrometry. COVID19 severity was defined using the WHO 7-point ordinal scale.Results84 COVID19 patients were included (mean age±SD 65.5±14.6 years;52.4% male), 91 non-COVID19 respiratory infection patients (age 65.7±16.7 years;49.5% male) and 42 non-infected controls (age 58.5±17.9;40% male). 1,748 proteins were significantly different (q-value≤0.05) in COVID19 neutrophils compared to those of non-infected controls. Major differences included a robust interferon response at baseline, with markers of neutrophil immaturity (CD10, CD71), increased neutrophil activation (CD64), and changes in metabolism which associated with COVID19 disease severity. Delayed recovery (WHO score 2–3) at day 29 was associated with significant changes in 1,107 proteins compared to the control population. Features of non-recovery included significantly reduced abundance of migratory receptors (e.g. C3AR1, LTB4R), integrins (CD11b, CD18), inhibitory molecules (e.g. SHP-1, SHIP-1) and indications of increased activation (CD64). Overall, ficolin and specific granule content was decreased in COVID19 patient neutrophils at day 29 compared with controls, however, comparing those who had recovered and those who had not, granule content was found to be significantly lower in the non-recovery group.ConclusionNeutrophils undergo significant changes in acute COVID19 associated with disease severity. Neutrophil proteomics revealed that these cells may have an ongoing role in non-recovered patients, including profiles associated with increased potential for neutrophil activation and reduced migratory capacity, highlighting neutrophils as potential therapeutic targets in long COVID19.

Results from the STAR-COVID19 trial, a double-blind RCT of stabilised, synthetic sulforaphane in hospitalised patients with suspected COVID19

Introduction and ObjectivesThe transcription factor, Nrf2, can directly promote beneficial anti-oxidant and anti-inflammatory responses. In the STAR-COVID19 trial, hospitalised patients with confirmed or suspected COVID19 were treated with stabilised, synthetic sulforaphane (S-SFN)—an Nrf2 inducer—to evaluate impact on clinical status and systemic inflammation.MethodsDouble-blind, randomised, placebo-controlled trial of S-SFN (300 mg S-SFN or placebo once daily for 14 days;allocation ratio 1:1;EudraCT 2020–003486-19) in Dundee, UK. Inclusion criteria were age ≥18 years, suspected or confirmed COVID19 or pneumonia and CURB65 score ≥1. The primary outcome was the 7-point WHO Clinical Status scale at day 15. Secondary outcomes included time to clinical improvement, length of hospital stay, and mortality. Blood samples were taken on days 1, 8 and 15 for exploratory analyses. To assess Nrf2 activity and inflammation, 45 serum cytokines were measured using the Olink Target48 panel and mRNA sequencing of peripheral blood leukocytes performed. Further, as key immune cells in COVID19 responses, select neutrophil functions such as migration, phagocytosis and extracellular trap formation were evaluated.Results133 participants (77.4% PCR-confirmed SARS-CoV-2 infection) were randomized from Nov 2020 to May 2021. 68 received placebo (61.8% male;age 63.6±13.8) and 65 received S-SFN (53.8% male;age 61.6±12.7).S-SFN treatment did not improve clinical status at day 15 (Intention-to-treat population;adjusted OR 0.87, 95%CI 0.41–1.83, p=0.712) and the trial was terminated due to futility. Time to clinical improvement (adjusted HR 1.02(0.70–1.49)), length of hospital stay (aHR 0.84(0.56–1.26)), or 29-day mortality (aHR 1.45(0.67–3.16)) were not improved with S-SFN treatment.230 samples in total were utilised for serum cytokine measurement;Nrf2 targets implicated in cytokine storm, including IL6, IL1β and TNFα, were not significantly changed by S-„SFN treatment. Interestingly, serum TGFα was significantly increased at day 15 in those receiving S-SFN compared with placebo (p=0.004;linear mixed effects model). S-SFN treatment did not significantly affect neutrophil functions investigated.ConclusionS-SFN treatment did not improve clinical status at day 15 or modulate key inflammatory cytokines—however, changes in other factors were indicated. Further analyses, including transcriptomics, to delineate drug activity are currently ongoing.