Cadila believes it has silver bullet to fight COVID-19

Can Interferon alfa-2b treat COVID-19 effectively?
Sohini Dutt reports.

Ahmedabad-based pharmaceutical major Cadila Healthcare has emerged at the forefront of India's battle to fight the coronavirus disease.

After announcing research on two vaccine candidates, work on developing rapid diagnostic kits and ramping up production of hydroxychloroquine, the company is now exploring the use of a biologic drug Interferon alfa-2b to treat COVID-19.

Recent studies have shown evidence of a direct antiviral effect of Interferon alfa-2b against the new coronavirus.

Cadila Healthcare (Zydus Cadila) has been commercially making Pegylated Interferon alfa-2b under the brand name Pegihep since 2011 for the treatment of Hepatitis B and C, with 150,000 doses being administered.

Pegihep is not yet licensed or approved for the treatment of COVID-19. However, it can be used as a 'compassionate use programme'.

Zydus has approached the department of biotechnology to investigate the role of Pegylated Interferon alfa-2b for COVID-19 and is ready to undertake clinical trials.

In-vitro studies have demonstrated that Interferon alfa-2b has antiviral effect against the novel coronavirus.

One study by the University of Texas Medical, Galveston, demonstrated around 10,000-fold reduction in-virus titre in cells that were pre-treated with Interferon alfa-2b 48 hours earlier.

The second by a group of universities in China, Australia, and Canada retrospectively analysed 77 moderate COVID-19 subjects in Wuhan and observed that those who received Interferon alfa-2b showed significant reduction in the duration of virus-shedding period and even in levels of the inflammatory Cytokine IL-6.

This suggests that if a long-acting molecule like Pegylated Interferon alfa-2b is given early on in the infection, the patient suffering from COVID-19 will have significant benefit, as the viral load is reduced, lesser inflammatory elements are produced, and the virus-eliminating specific immune response is generated.

When the human body contracts an infection due to a viral attack, it produces a group of molecules called Type 1 interferons as a first line of defence.

Interferon alfa-2b is one such Type 1 Interferon molecule that not only slows down the viral replication, but also helps activate the two arms of our immune system -- Innate, for immediate killing of the virus, and Adaptive, for long-lasting immunity.

To make it more effective, the molecule is coupled with polyethylene glycol to produce a new molecule called Pegylated Interferon alfa-2b that has the same functionality as Interferon alfa-2b, but remains in the body longer and therefore, requires only once-a-week injection, thus, providing a much better efficacy profile.

"Pegylated Interferon alfa-2b emerges as one such possibility with its potential to reduce virus titres when given earlier in the disease and offering better clinical outcomes," says Sharvil Patel, managing director, Cadila Healthcare.

"We are working with the US Food and Drug Administration and have opened an investigational new drug filing for Pegylated Interferon alpha-2b for the treatment of COVID-19," says Patel.

Apart from Interferon, the company has already increased its capacity to make both raw material and formulation of hydroxychloroquine after the drug was touted as useful by several countries as a preventive to be used by health care professionals and patient caregivers.

"This month we are making 10 tonnes of the API that can make 100 million tablets and next month we will make 30 tonnes of the API that will make another 150 million tablets," says Pankaj Patel, chairman, Zydus Cadila.

As a temporary measure, production of hydroxychloroquine is happening at its Ahmedabad plant. Pankaj Patel says the Centre has procured around 100 million tablets and states together have procured 60 million to 70 million tablets.

It is also working on an accelerated vaccine development programme which is currently in the animal testing stage and if the results are successful, it should enter clinical studies in the second quarter of this financial year.

Zydus has two vaccine candidates -- a DNA vaccine -- and another, a live weakened recombinant measles vaccine against COVID-19.

Zydus recently got approval to import rapid antibody kits for COVID-19 diagnosis from China, and is working to develop an indigenous kit.