A randomised, double-blind, placebo-controlled, multicentre clinical trial of AZD1656 in diabetic patients hospitalised with COVID-19: The ARCADIA Trial - implications for therapeutic immune modulation

BACKGROUND

A potential immunotherapeutic role for AZD1656 (a glucokinase activator) in the treatment of COVID-19 was hypothesized. The ARCADIA trial investigated the safety and efficacy of AZD1656 in diabetic patients admitted to hospital with COVID-19.

METHODS

The ARCADIA trial was a Phase II randomised, double-blind, placebo-controlled clinical trial. Adult diabetic patients, admitted with COVID-19, were recruited at 28 hospitals in the UK, Romania and Czech Republic and randomly assigned (1:1) to receive AZD1656 tablets (100mg twice a day), or matched placebo, for up to 21 days, in addition to usual care. All involved were masked to treatment allocation. The primary endpoint was clinical improvement measured at Day 14. The Full Analysis Set (FAS) included all patients who received at least one dose of assigned treatment. ARCADIA is complete and registered with ClinicalTrials.gov (NCT04516759).

FINDINGS

Between 29 September 2020 to 16 April 2021, 170 patients were screened and 156 patients were randomised, three of whom did not commence treatment. Of the remaining 153, 80 were assigned to AZD1656 and 73 were assigned to placebo and included in the Full Analysis Set (FAS). The primary analysis showed no statistically significant difference between groups (AZD1656: 76·3%; Placebo: 69·9%, p=0·19). There was no difference in the number of adverse events between groups (AZD1656: 35·7%; Placebo: 33·3%). Mortality was lower in the AZD1656 group compared to the placebo group (AZD1656: four (5%); Placebo: nine (12·3%), p=0·090)). At Day 7 there were zero deaths in the AZD1656 group compared to six deaths in the placebo group (p=0·011, post hoc). A difference between groups in time to hospital discharge was also seen (p=0·16). Immunophenotyping data suggested that AZD1656-treated patients had a less pro-inflammatory immune response and a better adaptive immune response than those treated with placebo.

INTERPRETATION

Although the trial did not achieve its primary endpoint, AZD1656 was associated with a decrease in deaths and a reduction in the duration of hospitalisation, as compared to Placebo. Immunophenotyping and immunochemistry indicated an immunomodulatory effect of AZD1656. The trial suggests a beneficial therapeutic effect of AZD1656 and identifies a new therapeutic concept: small molecule activation of endogenous homeostatic immune cells which themselves become the therapeutic agent within the body. Phase 2 trials of this size carry the risk of false positive results and confirmation of these results in a larger clinical trial is now required.

FUNDING

UK Research and Innovation (UKRI) 'Innovate UK' programme and Excalibur Medicines Ltd.

ARCADIA study protocol: a phase II, randomised, double-blind, placebo-controlled clinical trial to assess the safety and efficacy of AZD1656 in patients with diabetes hospitalised with suspected or confirmed COVID-19

INTRODUCTION

COVID-19, caused by SARS-CoV-2, remains a global pandemic that has affected more than 100 million people worldwide with over 4.8 million deaths as of October 2021. Patients with diabetes have both an increased susceptibility to SARS-CoV-2 infection, enhanced disease severity and increased risk of mortality. The challenge presented in these patients is both to improve glycaemic control-which itself may confer a survival advantage-and to help maintain or restore immunological homeostasis. The specific glucokinase activator AZD1656 may address both of these challenges via its glucose-lowering effect and its immunological mechanism of action. The aim of the Alleviation of cardioRespiratory complications in patients with COVID-19 And DIAbetes (ARCADIA) trial is to investigate this hypothesis and determine whether AZD1656 can improve clinical outcomes for these patients.

METHODS AND ANALYSIS

ARCADIA is a double-blind, placebo-controlled, interventional study of AZD1656 in 150 patients with either type 1 or type 2 diabetes who have been admitted to hospital with COVID-19. Eligible, consented patients will be randomised in a 1:1 manner to receive either active drug or matched placebo tablets while they are in hospital. All patients will receive the usual and current standard of care for patients with COVID-19 in that hospital. Clinical and laboratory data will be collected and assessed at baseline and throughout their participation in the study. Data will be captured in the case report form, which will be electronically archived at the end of the trial in the trial master file. The WHO 8-point Ordinal Scale for Clinical Improvement will be used to measure clinical outcome for the primary endpoint of the trial.

ETHICS AND DISSEMINATION

Ethical approval has been obtained from the East Midlands-Leicester South Ethics Committee (REC 20/EM/0198) in the UK, from the National Bioethics Committee of Medicines and Medical Devices in Bucharest, Romania, and from the Ethics Committee IKEM a TN in Prague, Czech Republic. All study-related data will be used by the sponsor in accordance with local data protection law. In the UK, all patient identifiable data will be stored on a password-protected National Health Service N3 network with full audit trail. Anonymised data will be stored in an ISO27001 certificated data warehouse.

TRIAL REGISTRATION NUMBER

EudraCT 2020-002211-21, NCT04516759.

Clinical evaluation of a novel on-strip calibration method for blood glucose measurement

This study evaluated a novel technology for improving accuracy of self-monitoring of blood glucose (SMBG). The technology calibrates each and every test by measuring the response from a predetermined amount of glucose present in the sample chamber of each test strip. SMBG test strips were modified to include a lid coated with a fast dissolving formulation containing glucose. These test strips were characterized for hematocrit (Hct) and temperature induced error response to develop a calibration algorithm. The modified test strips were used in a clinical evaluation involving fingerstick blood samples from 160 subjects. Experiments involving Hct and temperature induced errors show that the technology generates a signal characteristic of the error conditions in any particular test, but independent of glucose concentration, allowing a correction algorithm to be derived. The approach substantially reduced Hct and temperature derived errors. Clinical evaluation using fingerstick blood directly applied to prototype strips showed the error (measured as MARD) was reduced from 11.1 to 5.9% by the on-strip correction approach and the number of outliers reduced by approximately 90%. This technology could improve the accuracy and precision of glucose monitoring systems and so reduce decision errors particularly in clinical situations where hematocrit and temperature may be significant confounders.