Thai-American COVID vaccine enters phase 3 human trial

A vaccine jointly developed by New York’s Mt. Sinai Hospital, Thailand’s National Vaccine Institute and the University of Texas has entered a phase 3 human trial in northern Thailand to determine its safety and efficacy as a potential anti-COVID-19 booster shot.

Should the trial prove successful, it could be a major step toward achieving vaccine equity – making effective formulations just as available in developing and lower-income countries as in wealthier, more advanced nations.

The collaboration underscores Thailand’s strengths in public health, the medical sector, and research. The Kingdom has earned a sterling reputation by undertaking massive phase 3 human trials for other vaccines, including candidate vaccines for HIV, and by building a public health system that has been praised by the United Nations.

The new COVID vaccine uses NDV technology, which makes it easier and more economical to produce than mRNA vaccines. Scientists believe that it should be just as effective. It also does not require the strong refrigeration needed to store mRNA vaccines. Many developing countries lack cold-chain storage, making it a challenge to use the mRNA versions.

If the above trial produces positive results, Thailand would be in a position to manufacture and distribute the NDV vaccine to lower-income nations struggling to access, pay for or provide the logistics for mRNA vaccines. Thailand could help boost global vaccine security in the inevitable event of another pandemic.

Kriangkrai Prasert, Research Director for the project, said that phase 2 trials for safety showed the vaccine, named HXP-GPOVac, caused fewer side effects than the mRNA versions while indicating that it is just as effective.

NDV stands for Newcastle Disease Virus, and the vaccine uses cells from a bird virus. NDV technology has shown promise for treating a wide range of diseases, including some cancers.

This NDV-based vaccine project was the result of a collaboration with the PATH Center for Vaccine Innovation and Access, Icahn School of Medicine at Mount Sinai in New York, NY; the University of Texas at Austin in the United States; and three vaccine manufacturers in Brazil, Viet Nam, and Thailand.

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