Effect of parenteral L-carnitine in hospitalized patients with moderate to severe COVID-19: A randomized double-blind clinical trial

Introduction: Proinflammatory responses have an important role in developing coronavirus disease 2019 (COVID-19). L-carnitine (LC) has been known to possess anti-inflammatory, anticoagulant, and antiviral effects. So, we aimed to evaluate the efficacy of LC in hospitalized patients with moderate-to-severe COVID-19. Methods: This double-blind, placebo-controlled, randomized clinical trial was conducted on hospitalized patients with moderate to severe COVID-19. The patients were randomized (1:1) to receive LC (n = 50) at a dose of 20 mg/kg or matching placebo (n = 51) from normal saline once daily for 14 days or until hospitalization and standard care. The primary outcome was hospital mortality and disease severity according to the World Health Organization's clinical progression scale. We also assessed the free carnitine level at baseline and the end of the study. C-reactive protein (CRP), ferritin, D-dimer, lactate dehydrogenase (LDH), and improvement of respiratory conditions were chosen as secondary outcomes. Results: From 104 patients who met the inclusion criteria, 101 individuals' data were analyzed. The LC group showed a significant reduction in LDH levels (P = 0.003), although CRP, ferritin, and D-dimer levels did not significantly differ from the placebo group. Also, no significant difference was observed in disease severity, oxygenation status, hospital mortality, or hospital stay between the two groups. Additionally, there was no increase in serum-free carnitine levels in the LC group (P > 0.05 for all). Conclusion: The results of the current study did not support the superiority of LC over placebo in improving oxygenation, decreasing mortality, and hospital stay, as well as CRP, ferritin, and D-dimer in moderate to severe COVID-19 patients. Trial Registration: IRCT20170609034406N10; https://en.irct.ir/trial/60306.