Changes in QTc interval after hydroxychloroquine therapy in patients with COVID-19 infection: a large, retrospective, multicentre cohort study

Cardiac findings in a phase II double-blind randomized placebo-controlled trial of combination therapy (HAZDPac) to treat COVID-19 patients

OBJECTIVE

Hydroxychloroquine paired with Azithromycin, Vitamin C, Vitamin D, and Zinc (HAZDPac), was used as a multidrug therapy method to treat COVID-19 illness and superimposed secondary bacterial pneumonia. Concerns have been raised though about such combinations regarding cardiac QTc interval prolongation and risks of arrhythmias, which we set out to address in this study.

DESIGN

We evaluated cardiac safety in a Phase II Double-Blind Randomized Placebo-Controlled Trial of Combination Therapy to Treat COVID-19 Infections study, conducted by ProgenaBiome. Acutely ill patients with COVID-19 had QTc intervals recorded in an outpatient setting utilizing a continuously worn EKG monitor for the duration of the 10 days treatment. QTc intervals were normally distributed. Two-sample t-tests were used to measure any significant differences in QTc intervals between treatment and placebo groups.

RESULTS

Between March 2020 and June 2021, 118 COVID-19 patients were recruited and signed informed consent, of which 83 were enrolled for a Double-Blind Randomized Placebo-Controlled Trial. Of the 83, 52 patients were randomly assigned to receive HAZDPac treatment, and 31 patients to receive placebo. Overall, and in stratified analysis by gender, maximum QTc values of patients in the treatment arm were normal and no differences were observed when compared to maximum QTc values from patients in the placebo arm (p ≥ 0.15). There were no adverse events related to HAZDPac treatment.

CONCLUSION

We found that the outpatient treatment of COVID-19 patients with HAZDPac which includes Hydroxychloroquine and Azithromycin, was not associated with prolongation of QTc compared to placebo and QTc remained within normal range.

CLINICAL TRIAL

Clinical Trial NCT04482686, clinicaltrials.gov, date of registration 07/21/2020.

Hydroxychloroquine safety in Covid-19 vs non-Covid-19 patients: analysis of differences and potential interactions

BACKGROUND

The use of hydroxychloroquine (HCQ) in the first COVID-19 epidemic wave raised safety concerns.

RESEARCH DESIGN AND METHODS

Adverse reactions (ADR) suspected to be induced by HCQ and submitted to the Spanish Pharmacovigilance Database were studied. A disproportionality analysis was performed to determine adverse effects reported in non-Covid and Covid patients. To explore potential drug-drug interactions, Omega (Ω) statistics was calculated.

RESULTS

More severe cases were reported when used in COVID-19. Main differences in frequency were observed in hepatobiliary, skin, gastrointestinal, eye, nervous system and heart ADRs. During the COVID-19 pandemic, high disproportionality in reports was found for Torsade de Pointes/QT prolongation with a ROR (-ROR) of 132.8 (76.7); severe hepatotoxicity, 18.7 (14.7); dyslipidaemias, 12.1 (6.1); shock, 9.5 (6.9) and ischemic colitis, 8.9 (2.6). Myopathies, hemolytic disorders and suicidal behavior increased their disproportionality during the pandemic. Disproportionality was observed for neoplasms, hematopoietic cytopaenias and interstitial lung disease in the pre-COVID-19 period. Potential interactions were showed between HCQ and azithromycin, ceftriaxone, lopinavir and tocilizumab.

CONCLUSIONS

The use of HCQ during the Covid-19 pandemic changed its ADRs reporting profile. Of particular concern during the pandemic were arrhythmias, hepatotoxicity, severe skin reactions and suicide, but not ocular disorders. Some signals identified would require more detailed analyses.