Single-shot rabies vaccine shows promising immune response, researchers say

A new single-shot rabies vaccine shows promising results in protecting against the disease, early research suggests.

Phase 1 clinical trial results also indicate the jab is safe.

The new vaccine aims to address some of the main problems with existing rabies vaccines, which is that they are expensive and require multiple doses.

Researchers say a new rabies vaccine could help prevent thousands of deaths from the disease every year.

We’re very hopeful that expanded trials... could enable routine, affordable, single-dose vaccination against this devastating disease

Associate Professor Sandy Douglas, chief investigator of the trial at the Jenner Institute, University of Oxford, said: “We’re absolutely delighted with these early results – the vaccine has performed even better than we had expected.

“The problems with existing rabies vaccines are that they are expensive and require multiple doses.

“We’re very hopeful that expanded trials in countries affected by rabies will prove that this new vaccine could enable routine, affordable, single-dose vaccination against this devastating disease for people living in such areas.”

The trial was conducted at the University of Oxford and it was the first time the novel rabies vaccine had been used in human volunteers.

The aim of the study was to look at safety and measure immune responses from the vaccine.

Twelve volunteers were recruited, with three receiving a low dose, three receiving a medium dose and six receiving a high dose of the ChAdOx2 RabG jab.

Researchers found strong immune responses against rabies were generated by the vaccine, with all volunteers who received a medium or high dose developing levels of rabies-neutralising antibodies above the World Health Organisation protective threshold within two months.

There were no serious side effects or safety concerns reported during the trial.

The study also looked at the longer term effects of the vaccine.

It found six of the seven middle and high-dose recipients who returned for an additional follow-up one year after vaccination maintained neutralising antibody levels above the protective threshold.

According to the researchers, this demonstrates the immune response from the vaccine persists over time.

Dr Daniel Jenkin, lead clinical research fellow of the trial, said: “New rabies vaccines based on modern vaccine technologies could become important tools in preventing the tens of thousands of rabies deaths that occur annually.

“Our strong early clinical trial data with ChAdOx2 RabG supports further development of this approach.”

Researchers hope the findings, published in The Lancet Microbe, will support further development of the vaccine and allow larger clinical trials to take place in the future.