Kourosh H. Ebrahimi

Bio: Kourosh H. Ebrahimi is an academic researcher from King's College London. The author has contributed to research in topics: Randomized controlled trial & Nafamostat. The author has co-authored 1 publications.

Randomised Controlled Trial of Intravenous Nafamostat Mesylate in COVID Pneumonitis: Phase 1b/2a Experimental Study to Investigate Safety, Pharmacokinetics and Pharmacodynamics (preprint)

Abstract: Background: Many repurposed drugs have progressed rapidly to Phase 2 and 3 trials in COVID19 without characterisation of Pharmacokinetics /Pharmacodynamics including safety data. One such drug is Nafamostat Mesylate. Methods: We present the findings of a phase Ib/II open label, platform randomised controlled trial 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. Nafamostat was administered as an intravenous infusion at a dose of 0.2mg/kg/hour for a maximum of seven days. The analysis population included those who received any dose of the trial drug and all patients randomised to SoC. Results: Data is reported from 42 patients, 21 of which were randomly assigned to receive intravenous Nafamostat. 78% of Nafamostat-treated patients experienced at least one AE compared to 57% of the SoC group. The Nafamostat group developed significantly higher plasma creatinine levels and had a lower number of oxygen free days (posterior mean difference 10.57 micromol/L, 95% HPD interval 2.43 - 18.92, rate ratio 0.55- 95% HPD interval 0.31- 0.99 respectively). There were no other statistically significant differences in endpoints between Nafamostat and SoC. PK data demonstrated that intravenous Nafamostat was rapidly broken down to inactive metabolites. We observed no significant anticoagulant effects in thromboelastometry. Participants in the Nafamostat group had higher D-Dimers. Interpretation: In hospitalised patients with COVID-19, we did not observe evidence of anti-inflammatory, anticoagulant or antiviral activity with intravenous Nafamostat. Further evaluation of Nafamostat delivered via a different route may be warranted. Clinical Trial Registration Details: This trial has been registered on ISRCTN (https://www.isrctn.com/) ISRCTN14212905, and Clinicaltrials.gov (https://www.clinicaltrials.gov/) NCT04473053. Funding Information: DEFINE was funded by LifeArc (an independent medical research charity under the STOPCOVID award to the University of Edinburgh. We also thank the Oxford University COVID-19 Research Response Fund (BRD00230). Declaration of Interests: The authors report no conflict of interests. Ethics Approval Statement: The DEFINE trial has received full ethical approval from Scotland A REC (20/SS/0066), the MHRA (EudraCT 2020-002230-32) and NHS Lothian. Written informed consent was taken by trial clinicians prior to any trial procedures being performed. If a patient lacked capacity, consent could be provided by their next of kin.

Comparison of Preprint Postings of Randomized Clinical Trials on COVID-19 and Corresponding Published Journal Articles: A Systematic Review.

Abstract: Importance Randomized clinical trials (RCTs) on COVID-19 are increasingly being posted as preprints before publication in a scientific, peer-reviewed journal. Objective To assess time to journal publication for COVID-19 RCT preprints and to compare differences between pairs of preprints and corresponding journal articles. Evidence Review This systematic review used a meta-epidemiologic approach to conduct a literature search using the World Health Organization COVID-19 database and Embase to identify preprints published between January 1 and December 31, 2021. This review included RCTs with human participants and research questions regarding the treatment or prevention of COVID-19. For each preprint, a literature search was done to locate the corresponding journal article. Two independent reviewers read the full text, extracted data, and assessed risk of bias using the Cochrane Risk of Bias 2 tool. Time to publication was analyzed using a Cox proportional hazards regression model. Differences between preprint and journal article pairs in terms of outcomes, analyses, results, or conclusions were described. Statistical analysis was performed on October 17, 2022. Findings This study included 152 preprints. As of October 1, 2022, 119 of 152 preprints (78.3%) had been published in journals. The median time to publication was 186 days (range, 17-407 days). In a multivariable model, larger sample size and low risk of bias were associated with journal publication. With a sample size of less than 200 as the reference, sample sizes of 201 to 1000 and greater than 1000 had hazard ratios (HRs) of 1.23 (95% CI, 0.80-1.91) and 2.19 (95% CI, 1.36-3.53) for publication, respectively. With high risk of bias as the reference, medium-risk articles with some concerns for bias had an HR of 1.77 (95% CI, 1.02-3.09); those with a low risk of bias had an HR of 3.01 (95% CI, 1.71-5.30). Of the 119 published preprints, there were differences in terms of outcomes, analyses, results, or conclusions in 65 studies (54.6%). The main conclusion in the preprint contradicted the conclusion in the journal article for 2 studies (1.7%). Conclusions and Relevance These findings suggest that there is a substantial time lag from preprint posting to journal publication. Preprints with smaller sample sizes and high risk of bias were less likely to be published. Finally, although differences in terms of outcomes, analyses, results, or conclusions were observed for preprint and journal article pairs in most studies, the main conclusion remained consistent for the majority of studies.