New Delhi: With India witnessing a super-surge in Omicron-triggered Covid cases, people across age groups are now rushing to hospitals and healthcare providers asking for a dose of the monoclonal antibody cocktail therapy -- popularised by former US President Donald Trump in 2020.

Promising to reduce the severity of Covid-19 disease in a certain high-risk age-group with co-morbidities, this antibody cocktail, however, is not for everyone -- not at all for those infected with Omicron, warn health experts.

A single dose of the cocktail therapy costs nearly Rs 65,000.

Delhi-based Lakshmikant (name changed upon request), aged 64, recently got his dose of monoclonal antibody cocktail therapy at Max Hospital in Saket.

Infected with the Delta variant in the month of December -- when India was yet to see Omicron surge -- he was administered the dose after much consultation, and is safe at home now.

Flooded with calls for antibody cocktail therapy, Vivek Nangia, head of the pulmonology department at Max Super Speciality Hospital in Saket, said that the therapy is not effective against the Omicron variant as there is no data available yet.

"The awareness about antibody cocktail therapy has gone up significantly in India. And people do ask for it. However, it is not effective against Omicron," Nangia told IANS.

"If a patient is not improving in five days' time and continues to experience significant symptoms, that is when we consider monoclonal antibody therapy for the patient," he informed.

We have seen the emergence of several such alternative methods to treat severe Covid-19 in the past, like Remdesivir, Tocilizumab, Hydroxychloroquine and plasma therapy, which faded away with new and deadly mutants arriving on the scene.

Monoclonal antibody therapy, once hailed as 100 per cent effective in stopping Covid-19 in its tracks, has been defeated by the new super-mutant Omicron variant, according to a latest global study involving researchers from the US, Japan and Switzerland.

Monoclonal antibodies are proteins designed to attach to a specific target, in this case the spike protein of SARS-CoV-2, which the virus uses to enter human cells. Several studies have shown that monoclonal antibody therapy can stop Covid infection's progression to ICU admissions and death.

The global team of researchers analysed the efficacy of monoclonal antibody treatments from major pharma companies.

The findings, posted on preprint server biorxiv, and not peer-reviewed yet, revealed that the therapy developed by pharma giants like Regeneron, Lilly, and Celltrion "completely lost neutralising activity" when faced with Omicron.

However, monoclonal antibody treatments by AstraZeneca and Vir Biotechnology were "minimally affected", or in other words, "retained partial activity".

The recent emergence of the highly-transmissible B.1.1.529 Omicron variant is especially concerning because of the number of mutations -- more than 30 in the spike protein.

"Our results suggest that several, but not all, of the antibody products in clinical use will lose efficacy against the B.1.1.529 Omicron variant and related strains," wrote corresponding author Michael S. Diamond, from the Washington University's school of Medicine, in the study.

According to Arunesh Kumar, Senior Consultant and Head, Department of Pulmonology, Paras Hospitals, Gurugram, with the Omicron variant coming into the picture, the efficacy of monoclonal antibody has come into question as it was useful with Delta variant in preventing severe disease and hospitalisation.

"People with co-morbidities and early symptoms, however, are getting this treatment. It remains to be seen how effective it will be with Omicron. Another oral drug, Molnupiravir, is also being used in Covid-positive patients with mild symptoms and comorbidities," Kumar told IANS.

Another latest study led by researchers from Columbia University in the US, in collaboration with scientists at the University of Hong Kong, said that Omicron has the potential to evade the immune protection conferred by vaccines and natural infection, as well as render most monoclonal antibody therapies ineffective.

The study suggested that all of the monoclonal antibody therapies currently in use and most in development are much less effective against Omicron, if they work at all.

Nangia said that a monoclonal antibody dose should basically be administered to someone who's been at a very high risk of developing a severe disease.

"It is for people above the age of 60, or somebody who has uncontrolled diabetes and hypertension and heart disease and there is a strong suspicion of the Delta variant," he told IANS.

(IANS)