In a recent article posted to Preprints with The Lancet*, investigators assessed the potential of high-dose coenzyme Q10 (CoQ10) treatment for long coronavirus disease (COVID).
The impact of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic on world civilization has been unprecedented, with more than 575 million confirmed COVID 2019 (COVID-19) cases thus far. Several studies illustrated that chronic, debilitating symptoms present among COVID-19 survivors, depicting the long-lasting clinical impact of SARS-CoV-2 infection.
Long COVID, also known as post-COVID-19 condition (PCC), refers to a variety of multi-organ symptoms that persist for over 12 weeks following SARS-CoV-2 infection. Although several theories on PCC pathogenesis exist, the fundamental mechanism is still not fully known. Interestingly, recent reports indicate that the peripheral blood mononuclear cells (PBMCs) from COVID-19 patients exhibit indications of mitochondrial dysfunction.
About the study
In the present phase 2 randomized crossover study, the researchers hypothesized that persistent mitochondrial dysfunction was the root cause of dyspnea, fatigue, muscle symptoms, and neurological symptoms in PCC patients. They investigated whether high-dose CoQ10 can lessen the number or severity of PCC-linked symptoms, offering a potential treatment approach, considering that CoQ10 can enhance mitochondrial function.
The current double-blind, placebo-controlled, 2×2 crossover interventional investigation included participants from two centers at the Gødstrup Hospital and Aarhus University Hospital in Denmark. They were randomized to receive either oral capsules containing 500 mg/day of CoQ10 or a placebo for six weeks and crossover treatment following a four-week washout phase.
The participants completed a PCC-symptom-specific and the EuroQol-5 Dimension (ED-5Q) questionnaire at five sessions during the 20-week trial period. The primary outcome measured the difference between the intervention and placebo groups in six weeks in the number or severity of PCC-associated symptoms. Participants who finished the two-dosing phase were only included in the primary assessment, although the safety evaluation included all subjects who received one dose.
The study results demonstrated that 121 subjects underwent randomization from 25 May 2021 to 22 September 2021, and 119 of them, 59 in group A and 60 in group B, completed both dosing phases. In the beginning, the average EQ-5D health index was 0.66, and the average PCC-linked symptom score was 43.06. The discrepancy between placebo and CoQ10 was not relevant where the mean-variance for the change in EQ-5D health index was 0.01, and the PCC-associated symptom score was -1.18.
The scientists found that overall health conditions and symptoms connected to PCC across subjects were not significantly different between the impacts of high-dose CoQ10 and placebo. Further, they discovered no discernible disparity between CoQ10 and placebo in how the EQ-5D health index changed.
The team showed that the receipt of CoQ10 relative to placebo reduced the score for PCC-related symptoms by an extra 1.18 points. When they looked at seven sets of symptoms to determine whether CoQ10 has any organ-specific benefits, none of the outcomes were statically relevant. Besides, it had the highest positive effects on neurological complaints. Overall, the investigators discovered no significant differences between CoQ10 and placebo in reducing PCC-related symptoms, although they noticed a slight pattern toward CoQ10 possessing potentially positive effects.
Remarkably, independent of the treatment plan, the researchers discovered a significant 5.85-point decrease in the average PCC-associated symptom scores between the initial and the second visit. This finding could be explained by the subjects’ acknowledgment of PCC-linked symptoms and enrollment in a clinical interventional trial, which may have led to a placebo-driven improvement in their symptoms.
The authors also observed that the entire cohort experienced a significant overall improvement in the EQ-5D health index from 0·66 to 0·71 between the index and the final week 20 follow-up timestamps. Similarly, PCC-associated symptom scores also improved from 42·63 to 35·80. Indeed, both enhancements were driven mainly by the initial progress in both arms.
The authors claimed that the current research was the first placebo-controlled randomized crossover study to examine whether a registered medical product will lessen the frequency or intensity of PCC-associated symptoms.
The study findings showed that CoQ10 therapy compared to placebo does not significantly lessen the frequency or intensity of PCC-linked symptoms. The researchers noted that most subjects were recruited several months following the acute COVID-19 episode.
Since mitochondrial dysfunction was established relatively early during and after COVID-19 and CoQ10 medication was implemented too late in the PCC course to reverse the putative malfunction could be one explanation for the current poor outcomes. Another possibility could be that a six-week treatment period was too brief to determine CoQ10’s effects.
Preprints with The Lancet publishes preliminary scientific reports that are not peer-reviewed and, therefore, should not be regarded as conclusive, guide clinical practice/health-related behavior, or treated as established information.