Rationale and design of ENDEAVOR: A sequential phase 2b-3 randomized clinical trial to evaluate the effect of myeloperoxidase inhibition on symptoms and exercise capacity in heart failure with preserved or mildly reduced ejection fraction.

AIMS: Mitiperstat (formerly AZD4831) is a novel selective myeloperoxidase inhibitor. Currently, no effective therapies target comorbidity-induced systemic inflammation, which may be a key mechanism underlying heart failure with preserved or mildly reduced ejection fraction (HFpEF/HFmrEF). Circulating neutrophils secrete myeloperoxidase, causing oxidative stress, microvascular endothelial dysfunction, interstitial fibrosis, cardiomyocyte remodelling and diastolic dysfunction. Mitiperstat may therefore improve function of the heart and other organs, and ameliorate heart failure symptoms and exercise intolerance. ENDEAVOR is a combined, seamless phase 2b-3 study of the efficacy and safety of mitiperstat in patients with HFpEF/HFmrEF. METHODS: In phase 2b, approximately 660 patients with heart failure and ejection fraction >40% are being randomized 1:1:1 to mitiperstat 2.5 mg, 5 mg or placebo for 48 weeks. Eligible patients have baseline 6-min walk distance (6MWD) of 30-400 m with a <50 m difference between screening and randomization and Kansas City Cardiomyopathy Questionnaire total symptom score (KCCQ-TSS) ≤90 points at screening and randomization. The dual primary endpoints are change from baseline to week 16 in 6MWD and KCCQ-TSS. The sample size provides 85% power to detect placebo-adjusted improvements of 21 m in 6MWD and 6.0 points in KCCQ-TSS at overall two-sided alpha of 0.05. Safety is monitored throughout treatment, with a focus on maculopapular rash. In phase 3 of ENDEAVOR, approximately 820 patients will be randomized 1:1 to mitiperstat or placebo. CONCLUSION: ENDEAVOR is the first phase 2b-3 study to evaluate whether myeloperoxidase inhibition can improve symptoms and exercise capacity in patients with HFpEF/HFmrEF.

The Impact of COVID-19 on the Initiation of Clinical Trials in Europe and the United States.

The coronavirus disease 2019 (COVID-19) pandemic has a major impact not only on public health and daily living, but also on clinical trials worldwide. To investigate the potential impact of the COVID-19 pandemic on the initiation of clinical trials, we have descriptively analyzed the longitudinal change in phase II and III interventional clinical trials initiated in Europe and in the United States. Based on the public clinical trial register EU Clinical Trials Register and clinicaltrials.gov, we conducted (i) a yearly comparison of the number of initiated trials from 2010 to 2020 and (ii) a monthly comparison from January 2020 to February 2021 of the number of initiated trials. The analyses indicate that the COVID-19 pandemic affected both the initiation of clinical trials overall and the initiation of non-COVID-19 trials. An increase in the overall numbers of clinical trials could be observed both in Europe and the United States in 2020 as compared with 2019. However, the number of non-COVID-19 trials initiated is reduced as compared with the previous decade, with a slightly larger relative decrease in the United States as compared to Europe. Additionally, the monthly trend for the initiation of non-COVID-19 trials differs between regions. In the United States, after a sharp decrease in April 2020, trial numbers reached the levels of 2019 from June 2020 onward. In Europe, the decrease was less pronounced, but trial numbers mainly remained below the 2019 average until February 2021.