MC Explains I Tecovirimat, a promising drug for monkeypox; will India need it? 

A child affected by monkeypox, sits on his father's legs while receiving treatment at the centre of the International medical NGO Doctors Without Borders (Medecins sans frontieres - MSF), in Zomea Kaka, in the Lobaya region, in the Central African Republic. (Image for representation)

With a Delhi resident who had no history of international travel being confirmed to be suffering from monkeypox, concerns have been raised about the likelihood of the disease’s wider transmission in the community.

Experts say that unlike COVID-19, cases of monkeypox may not surge; it does not spread through airborne transmission of aerosols and droplets produced by an infected person, but through close skin contact and body fluids, and the transmission may be far easier to control.

But governments across the globe are now looking at vaccines and therapeutics that may be required to curb the outbreak that has now affected over 70 countries. The World Health Organisation (WHO) has declared monkeypox a “Public Health Emergency of International Concern”.

While smallpox vaccines are also considered to be effective against monkeypox, a drug that has caught everyone’s attention is Tecovirimat. How effective can this be against the viral illness and how can it be made available in India? Moneycontrol explains.

How does the drug work and how effective is it against monkeypox?

Tecovirimat, sold under the brand name Tpoxx and others, is an antiviral with activity against orthopoxviruses like smallpox and monkeypox. It is the first antipoxviral drug approved by the US Food and Drug Administrator and among the only two drugs—the other is brincidofovir— approved for treating monkeypox in the US and European Union.

In the US, two million doses of the drug, developed by Siga Technolohoes, are available as part of the strategic national stockpile in preparation for a potential bioterror attack.

The medicine, mostly administered orally, works by blocking cellular transmission of the virus, preventing the disease and has been effective in laboratory testing. It has been shown to protect animals from monkeypox and rabbitpox and causes no serious side-effects in humans.

No large-scale clinical trials have been conducted to prove its efficacy, but a small study in the UK showed that it was more effective in treating monkeypox than Brincidofovir, an antiviral drug used to treat smallpox.

The study suggested carrying out more studies to examine its usefulness in treating monkeypox, a disease that had largely been endemic to parts of Africa before 2011.

Also read: Government rushes to raise lab capacity as first case of monkeypox without international travel history is reported in India

Indian experts such as Dr Parinita Kaur, an internal medicine specialist with Aakash Healthcare, pointed out that while data is not available on the effectiveness of Tecovirimat in treating monkeypox, data from tests done on animal species have shown that it is effective in treating diseases caused by orthopoxviruses, a genus of viruses.

“Clinical trials on humans show that the drug is generally safe with very few side effects,” she said.

Will the drug be required in India?

Dr Sushil Jain, consultant pulmonologist with Masina Hospital in Mumbai, said at least a limited stock of the medicine may be required.

Monkeypox spreads very slowly, unlike COVID-19, but there is some chance of it spreading, he said.

“So in some cases, when those immunocompromised contract the infection they may be required to be given this medicine to prevent complications in people with high risk,” said Jain. “Every person may not require some amount of stock. It will be required, but not too large a stock.”

It is important that India keep some stock ready so that it is available to those who need it at the right time, he said.

Jain, however, also said that as prevention is more important than treatment, preventative steps such as early diagnosis and quick isolation are also crucial and the option of vaccination should also be explored.

Dr Laxman Jessani, an infectious disease specialist with Apollo Hospitals in Navi Mumbai, too, said Tecovirimat is the drug of choice for treating monkeypox and will be useful in treatment of confirmed cases of the disease.

“But it is more important to focus on vaccination against monkeypox as it could be more beneficial,” he said.

How can the drug be made available in India if needed? 

Officials at the apex drug regulator, Central Drugs Standard Control Organisation, said that for a drug to be made available in India, in case it is under patent, companies need to enter into a licensing agreement with the innovator.

“Alternatively, if the innovator company is looking to sell the drug in India on its own, it can also apply for approval based on the clinical trial data,” said an official.

Also read: Monkeypox in India: No need to panic, say experts; call for stepped up diagnostics, preparation with smallpox vaccine

But whether or not emergency use authorisation is granted to the drug under the New Drug and Clinical Trial rules, 2019, without bridging studies, will depend on an assessment of monkeypox situation as a public health emergency locally, the official said.

Sandeep Rathod, a pharma legal expert who is with JB Chemicals, said a possible route to make the drug available in India can be on the lines of Remdesivir, an Ebola drug manufactured by Gilead Sciences that was repurposed for treating moderate to severe COVID-19 patients in many countries, including India.

Over 10 drugmakers from India entered into a licensing agreement with Gilead Sciences to make the generic version of the injectable drug and market it in India and several other low and middle-income countries during the peak of the COVID-19 pandemic.