No evidence IV vitamin C aids critically ill COVID-19 patients

IV drop

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Intravenous (IV) vitamin C does not reduce the need for life support or all-cause mortality for critically ill COVID-19 patients, according to a study published today in JAMA.

The findings come from two harmonized global studies, the Lessening Organ Dysfunction with Vitamin C for COVID-19 (LOVIT-COVID) trial and the Randomized, Embedded, Multifactorial Adaptive Platform Trial for Community-Acquired Pneumonia (REMAP-CAP). Both trials investigated the usefulness of vitamin C among hospitalized COVID patients after reports that the widely available vitamin lowered mortality rates from sepsis and some anecdotal evidence the vitamin helped minimize COVID-19 symptoms.

The LOVIT-COVID trial was blinded and placebo-controlled, whereas the REMAP-CAP trial was open label without placebo. In both trials, all participants received an IV infusion of vitamin C (50 mg/kg of body weight administered every 6 hours for 96 hours) and were followed for at least 21 days.

The trial enrollees came from 90 intensive care units (ICUs) on four continents and were treated from July 23, 2020, to July 15, 2022. In total, the LOVIT-COVID trial included 1,568 critically ill patients (1,037 in the vitamin C group and 531 in the control group; median age, 60 years; 35.9% were female).

Vitamin C potentially harmful

The median number of organ support–free days was 7 for the vitamin C group, compared with 10 for the control group (adjusted proportional odds ratio [OR], 0.88 [95% credible interval [CrI], 0.73 to 1.06]), and the posterior probabilities were 8.6% (efficacy), 91.4% (harm), and 99.9% (futility), the authors said.

For patients who were not critically ill and received vitamin C, the median number of organ support–free days was 22, the same as the placebo group.

Among critically ill patients, survival to hospital discharge was 61.9% for the vitamin C group, compared to 64.6% for the control group (adjusted OR, 0.92 [95% CrI, 0.73 to 1.17].

The results from this trial suggest that the use of vitamin C in hospitalised COVID-19 patients should be de-adopted.

"The results from this trial suggest that the use of vitamin C in hospitalised COVID-19 patients should be de-adopted," Francois Lamontagne, MD, of the University de Sherbrooke and co-lead investigator of these trials, said in a press release. "The results underscore the health and economic benefits of identifying and abandoning readily available interventions that are ineffective and potentially harmful to patients."

In an editorial on the study, the authors said the findings were concerning, as they showed the
"possibility that vitamin C is detrimental in patients with COVID-19 because the probability of harm exceeded 90% for organ support–free days in both critically ill patients and those who were not critically ill."

During the LOVIT trial, vitamin C was also shown to be futile for sepsis patients, leading to potentially dangerous organ dysfunction.

"Although the allure of vitamin C may continue to tempt clinicians, the results from the harmonized LOVIT-COVID and REMAP-CAP trials should lead clinicians to use therapies that have been demonstrated to be beneficial in patients with COVID-19 as opposed to one that is almost certainly ineffective and potentially harmful," the editorial authors wrote.

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