New Delhi: A phase 1 randomised clinical trial of a novel Nipah virus vaccine, led by US researchers, may soon pave the way to prevent the deadly infection. 

All three doses and regimens of the vaccine named HeV-sG-V demonstrated to be safe and generated an immune response, according to the researchers in the study published in the journal The Lancet.

"The induction of antibodies within 1 month of vaccination, along with the persistence afforded by two dosages, suggests the vaccine candidate has potential for reactive outbreak control and preventive use," said the team from Cincinnati Children's Hospital Medical Center (CCHMC).

First discovered in 1999 in Malaysia, Nipah virus (NiV) causes yearly outbreaks throughout south and southeast Asia, especially in India, with associated mortality rates of 40–75 per cent.

The World Health Organization has listed the Nipah virus as a high-priority pathogen because it kills up to 82 per cent of people who are infected, and there are no approved treatments or vaccines to prevent it.

The findings represent a “milestone” in the development of Nipah vaccines, said scientists from the Indian Council of Medical Research-National Institute of Virology in Uttar Pradesh, India, in an accompanying editorial in The Lancet.

The phase 1 trial included 192 healthy participants aged between 18 and 49 years.

While a single dose was not sufficient, two doses were immunogenic, with the highest response rates observed among vaccinees that received two doses of the 100 microgram of HeV-sG-V 28 days apart.

The neutralising antibody titres rose dramatically 7 days after the second investigational product dose.

Mild-to-moderate injection site pain was the most commonly reported adverse event. No serious adverse events, hospitalisations, or deaths were reported.

In the editorial, experts from the ICMR-NIV said the new vaccine should be tested in a larger, phase 2 trial, which could shed more light on safety, as well as how much protection the vaccine might provide.

Nipah virus disease is an emerging zoonotic infectious disease caused by the Nipah virus (NiV). It can cause acute encephalitis, severe respiratory illness, and, in many cases, death.