This commonly-prescribed antibiotic for COVID-19 treatment does not reduce hospitalization risk, death [details]

Antibiotics cannot cure viral diseases. Why? Because they are meant for the treatment of bacterial ailments. However, virus-caused respiratory illnesses can often leave the lungs vulnerable to secondary bacterial infections which can worsen the individual's prognosis. This is the case with COVID-19 as well. Now, a new study has found that azithromycin—an antibiotic commonly prescribed to patients battling the SARS-CoV-2 virus—does not prevent mild-to-moderate cases of the novel coronavirus infection from progressing to hospitalization or death.

According to a multi-institutional team of researchers, azithromycin was not effective in decreasing the risk of hospital admission or death among patients with mild-to-moderate COVID-19, in comparison to standard care. They also called for the ceasing of azithromycin's use for tackling the SARS-COV-2 virus in order to prevent the development of resistance towards the drug. The study was published in the journal The Lancet Respiratory Medicine.

"Our findings in mild-to-moderate COVID-19 managed in ambulatory care, taken together with trials in early disease in primary care and from trials in patients admitted to hospital with severe disease, suggest that azithromycin does not reduce hospital admissions, respiratory failure, or death compared with standard care, and should not be used in the treatment of COVID-19," the authors wrote.

Pinning Hopes on Existing Drugs

Since the beginning of the COVID-19 pandemic, a section of the scientific community has turned to existing medications to tackle the SARS-CoV-2 and the complications given rise by it. Compounds such as hydroxychloroquine, interferon and remedesiver have been looked at as potential treatment options, with only remedesiver receiving approval. Other drugs such as azithromycin have also been considered for the treatment of symptoms and infections accompanying COVID-19.

Azithromycin is an antibiotic that is used to treat a wide range of infections. These include trachoma, sinus infections, skin infections, Lyme disease, certain sexually transmitted infections, and most importantly, chest infections such as drug-resistant tuberculosis and pneumonia.

Due to its anti-inflammatory, antibacterial, and potential antiviral properties, it has been suggested that azithromycin can aid in the management of COVID-19. However, along with the lack of data from randomised controlled trials, several studiesAzithromycin COVID-19 have stated that azithromycin may not do much for patients with the viral infection.

Ascertaining Benefits of Azithromycin

The randomized clinical trial was conducted across 19 sites in the UK. 1192 patients were screened for the trial. They had presented to hospitals after being clinically diagnosed for highly probable or confirmed COVID-19 infection; with less than 14 days of symptoms, and considered ideal for hospital assessment initially, followed by assessment then observation and/or treatment at home.

Between 3 June 2020 and 29 January 2021, 298 patients—who were 18 years of age or above (mean age of 45·9 years)—were enrolled in the study. Among them, 292 were included in the final study. The participants were randomized to azithromycin group (1:1, 500 mg daily orally for 14 days) or to the home observation group. For the study, the difference in the proportion of patients with hospital admission or death from any cause during the course of 28 days was the outcome.

No Reduction in Risk of Death or Hospitalization

As anticipated, the authors found no difference between the control or azithromycin groups in the risk of progression of COVID-19 cases to death or hospitalization. According to the researchers, in comparison to previous studies, a higher dose of the drug (500mg per day) and longer duration (14 days) was chosen in order to guarantee that the current study sufficiently evaluated potential antibacterial, antiviral and anti-inflammatory benefits of azithromycin.

In some individuals, COVID-19 is said to have a viraemic phase (presence of virus in the bloodstream) accompanied by a high viral load and a late inflammatory phase. Thus, the evaluation of antiviral activity was required to be conducted at the preliminary stage of the infection before severe disease set in.

However, the exact dosage required for the triggering of an appropriate anti-inflammatory effect remains unknown. Therefore, long duration with a high dose of the drug was necessary for ensuring that the anti-inflammatory effect was tested. Especially, during the later stages of the innate/ acute phase of dysregulation of cytokines known as cytokine storms. A cytokine storm is an erratic response of the immune system where immune cells attack the body.

According to the authors, the findings of the current study, along with those of similar older studies, suggest that the widespread prescription of azithromycin must be curbed or stopped altogether. "We now know it is not effective against COVID-19 and we need urgently to protect against the very real threat of driving drug resistance to this precious class of antibiotics," they wrote.