Even as Covid-19 cases across the world cross 7.41 million, including 4,18,000 deaths, two of the leading names in the development of a vaccine — US firm Moderna Inc and China’s Sinovac Biotech Ltd — have made discernible progress with their experimental candidate.

In latest developments, Moderna Inc said a series of studies in mice of its mRNA-1273 vaccine has lent some assurance that it may not increase the risk of more severe disease even as the US firm prepares for the pivotal late-stage testing next month.

On the other hand, Chinese firm Sinovac Biotech’s inactivated vaccine — CoronaVac — is also set to enter phase 3 clinical trials in Brazil.

More than 100 potential Covid-19 vaccines are in various stages of development around the world. Among front runners currently in human trials are the Covid-19 vaccines being developed by AstraZeneca, Pfizer, BioNtech, Johnson & Johnson, Merck, Moderna, Sanofi and China’s CanSino Biologics.

US firm Moderna Inc, which has already started phase II trials for its vaccine candidate mRNA-1273, has finalised the phase III study protocol, which will include approximately 30,000 participants. The randomized, placebo-controlled trial is expected to begin in July.

The vaccine, being jointly developed by the US National Institutes of Health, has lent some assurance in studies on mice that it may not increase the risk of more severe disease and that one dose may provide protection against the novel coronavirus.

“The company remains on track to be able to deliver approximately 500 million doses per year, and possibly up to 1 billion doses per year, beginning in 2021 from the company’s internal US manufacturing site and strategic collaboration with Lonza,” the company said in a press release.

The vaccine also appeared to protect against infection by the coronavirus in the lungs and noses without evidence of toxic effects, the team wrote.

They noted the mice that received just one dose before exposure to the virus seven weeks later were “completely protected against lung viral replication,” suggesting a single vaccination prevented the virus from replicating in the lungs.

On May 6, the US Food and Drug Administration (FDA) completed its review of the company’s investigational new drug (IND) application for mRNA-1273 vaccine and on May 11, the FDA granted it fast track designation.

On May 18, Moderna announced initial data from the Phase 1 study of mRNA-1273 led by National Institute of Allergy and Infectious Diseases (NIAID). Last month, Moderna had released early-stage data that showed the vaccine successfully produced protective antibodies in a small group of healthy volunteers.

Sinovac Biotech vaccine status

Chinese firm Sinovac Biotech has signed an agreement with a drugmaker in Brazil to conduct the final phase of the three-part human testing of its CoronaVac vaccine, a Bloomberg report said.

Once approved by Brazilian authorities, Sinovac and Instituto Butantan will kick off the trial involving 9,000 people in July. The Brazilian drugmaker will get to license the Chinese vaccine and make it available in the South American country, Sinovac said.

Meanwhile, in preliminary findings, the Sinovac Biotech vaccine is found to be safe and capable of eliciting an immune response from human trials.

The CoronaVac vaccine hasn’t caused severe side effects and more than 90 per cent of people administered with the shot on a 14-day interval have induced neutralizing antibodies two weeks after inoculation, Sinovac said in a press release on Sunday.

Using a killed version of the coronavirus, Sinovac’s vaccine is among five Chinese experimental shots that have reached the crucial final stage of human testing before they can be approved for public use.

Oxford-AstraZeneca vaccine status

The AZD1222 vaccine, being jointly developed by British pharma giant AstraZeneca and Oxford University, is presently undergoing phase II trials with 10,000 volunteers. The late-stage trials of the vaccine will be conducted in Brazil.

Testing of the experimental Covid-19 vaccine in healthy volunteers had begun in Britain in April with over 1,000 people aged 18 to 55.

Meanwhile, AstraZeneca has struck a deal with Europe’s Inclusive Vaccines Alliance to supply up to 400 million doses. The alliance, forged by Germany, France, Italy and the Netherlands to speed up production of a vaccine, will take delivery of the vaccine by the end of 2020.

Earlier this month, AstraZeneca stated it had started to mass-produce its experimental vaccine and planned to roll out up to two billion doses in September.

The Cambridge-based firm has signed deals to produce 400 million doses for the US and 100 million for the UK if it is successful in human trials.

Johnson & Johnson vaccine status

Initially planned for September, American firm Johnson & Johnson said it had fast-tracked the start of human clinical trials for its recombinant Ad26.COV2-S vaccine by two months to the second half of July. The decision may allow J&J to take part in the massive clinical trials program — Operation Warp Speed — planned by the US government.

In March, J&J signed deals with the US government to create enough manufacturing capacity to produce more than 1 billion doses of its vaccine through 2021, Reuters reported.

“Based on the strength of the pre-clinical data we have seen so far and interactions with the regulatory authorities, we have been able to further accelerate the clinical development,” said Chief Scientific Officer Paul Stoffels.

The study will test the vaccine for safety and early signs of efficacy in 1,045 healthy volunteers aged 18 to 55 years, and in those aged 65 and older. The trial will take place in the United States and Belgium.

The company is also in talks with the National Institutes of Allergy and Infectious Diseases(NIAID) to start larger, late-stage trials ahead of schedule.

For developing the Covid-19 vaccine, the technology being applied is similar to the one used to develop their investigational Ebola vaccine, as well as vaccine candidates for the Zika virus, RSV and HIV.

Source: The Indian Express