RESUMO
RationaleHigh galectin-3 levels predict poor outcomes in patients with COVID-19. Galectin-3 activates monocytes and macrophages which are directly implicated in COVID-19 immunopathology and the cytokine storm. GB0139 is a potent thiodigalactoside galectin-3 inhibitor and may reduce the severe effects of the disease. We report safety and pharmacokinetics and pharmacodynamics of the inhaled galectin-3 inhibitor, GB0139, and assess clinical outcomes and key systemic inflammatory biomarkers in hospitalised patients with COVID-19 (ClinicalTrials.gov/EudraCT identifier: NCT04473053/2020-002230-32). MethodsAdults with COVID-19 requiring oxygen, and with pneumonitis on x-ray, were randomised to receive standard of care (SOC; including dexamethasone; n=21) or SOC plus 10 mg GB0139 twice daily for 48 hours, then once daily for [≤]14 days (n=20). ResultsPatients aged 27-87 years were enrolled from July 2020; the final patient completed the 90-day follow-up in April 2021. GB0139+SOC was well tolerated with no treatment-related serious adverse events reported. Incidences of adverse events were similar between treatment arms (40 with GB0139+SOC vs 35 with SOC). Plasma GB0139 was measurable in all patients after inhaled exposure, with moderate interpatient variability, and demonstrated target engagement with decreased circulating galectin (overall treatment effect post-hoc over days 2-7: p=0{middle dot}0099 vs SOC). Rate of decline in fraction of inspired oxygen (%) requirement was significantly greater in the GB0139+SOC arm with a posterior mean difference of -1{middle dot}51 (95% highest posterior density: -2{middle dot}90, -0{middle dot}189) versus SOC. Plasma levels of biomarkers associated with inflammation, coagulopathy, major organ function and fibrosis showed a downward trend versus SOC. ConclusionsGB0139+SOC was well tolerated and achieved clinically relevant plasma concentrations and target engagement. This, and the reduction in markers associated with inflammatory, coagulation, fibrosis, and reduction in inspired oxygen (%) over SOC alone, indicates the therapeutic potential for inhaled GB0139 in hospitalised patients with COVID-19.
RESUMO
Despite the success of vaccines and selected repurposed treatments, COVID-19 is likely to remain a global health problem and further chemotherapeutics are required. Many repurposed drugs have progressed rapidly to Phase 2 and 3 trials without characterisation of Pharmacokinetics (PK)/Pharmacodynamics (PD) including safety in COVID-19. One such drug is Nafamostat Mesylate (Nafamostat), a synthetic serine protease inhibitor with anticoagulant and anti-inflammatory properties. Preclinical data has demonstrated that it is has potent antiviral activity against SARS-CoV-2 by directly inhibiting the transmembrane protease serine 2 (TMPRSS2) dependent stage of host cell entry. MethodsWe present the findings of a phase Ib/II open label, platform randomised controlled trial (RCT), exploring the safety of intravenous Nafamostat in hospitalised patients with confirmed COVID-19 pneumonitis. Patients were assigned randomly to standard of care (SoC), Nafamostat or an alternative therapy. Secondary endpoints included clinical endpoints such as number of oxygen free days and clinical improvement/ deterioration, PK/PD, thromboelastometry, D Dimers, cytokines, immune cell flow cytometry and viral load. ResultsData is reported from 42 patients, 21 of which were randomly assigned to receive intravenous Nafamostat. The Nafamostat group developed significantly higher plasma creatinine levels, more adverse events and a lower number of oxygen free days. There were no other statistically significant differences in the primary or secondary endpoints between Nafamostat and SoC. PK data demonstrated that intravenous Nafamostat was rapidly broken down to inactive metabolites. We observed an antifibrinolytic profile, and no significant anticoagulant effects in thromboelastometry. Participants in the Nafamostat group had higher D Dimers compared to SoC. There were no differences in cytokine profile and immune cell phenotype and viral loads between the groups. ConclusionIn hospitalised patients with COVID-19, we did not observe evidence of anti-inflammatory, anticoagulant or antiviral activity with intravenous Nafamostat. Given the number of negative trials with repurposed drugs, our experimental medicine trial highlights the value of PK/PD studies prior to selecting drugs for efficacy trials. Given the mechanism of action, further evaluation of Nafamostat delivered via a different route may be warranted. This trial demonstrates the importance of experimental trials in new disease entities such as COVID-19 prior to selecting drugs for larger trials.
