Incidence of QTc interval prolongation in patients treated for covid-19 with Doubase C or Hydroxychloroquine-azithromycin at University Hospital of Kinshasa

Background: QTc prolongation has been described in COVID-19 patients treated with Hydroxychloroquine (HCQ) and Azithromycin (AZT) in western countries. In the Democratic Republic of the Congo (DRC), few studies have assessed the safety of these molecules, and neither have they for new molecules proposed for COVID-19 treatment, such as Doubase C. This study aimed to determine the incidence of QTc prolongation in COVID-19 patients treated with HCQ-AZT or Doubase C. Methods: This study was part of a randomized clinical trial. Data were collected from May 20, 2021, to January 15, 2022. Patients were randomized into two arms; one was treated with Doubase C and the other with HCQ-AZT at standard dosages. Only patients with mild to moderate COVID-19 were included. Results: A total of 261 patients were included. At inclusion, the two groups were comparable (52.5% men, 47.5% women, mean age 41±15 years. The incidence of prolonged QTc interval was 1.5% in the whole group (3.3% on the HCQ-AZT arm and 0% on the Doubase C arm). No ventricular arrhythmias or torsade de pointes, or cardiac arrest were observed. Conclusion: Unlike Doubase C, the HCQ-AZT strategy has a risk of QTc prolongation.