We are recruiting for a first in man clinical trial

Chelsea and Westminster Hospital NHS Foundation Trust and Imperial College London are recruiting for a first in man clinical trial, ‘RAB- Vac’, which is testing an investigational RNA based Rabies vaccine.

The aim of the study is to understand how safe the vaccine is and how well it stimulates an immune response. At this early stage of development, it is not designed to test whether the vaccine prevents rabies infection.

The trial will enrol healthy adults aged 18-50 years. Volunteers must meet strict eligibility criteria, including availability for all follow-up visits, avoidance of other vaccines during specified periods and agreement to use effective contraception. Importantly, they should not have previously received any type of rabies vaccine.

This study has been funded by the Coalition for epidemic preparedness innovations (CEPI) and this study has received infrastructure support in part by the NIHR Imperial Biomedical Research Centre (BRC).

Rabies remains one of the most recognised zoonotic infections worldwide and continues to cause significant loss of life despite being entirely preventable. In this post Dr Maithili Varadarajan, from Imperial’s Department of Infectious Disease, explains how a new RNA-based Rabies vaccine is being developed and trialled by Imperial College London and Chelsea and Westminster Hospital Foundation NHS Trust to address this.

What is Rabies and why is this still a problem today?

Rabies is a viral disease that attacks the brain and nerves, usually spreading to humans through the bite or scratch of an infected mammal, most often a dog. Early symptoms such as fever, headache, and tiredness resemble those of many other common illnesses, but as the virus reaches the brain, it causes severe neurological problems, including agitation, confusion, hallucinations, and difficulty swallowing. At that stage, the disease is almost always fatal.

Although preventable, rabies remains a significant global health problem today, causing approximately 60,000 cases each year, with most infections occurring in Asia and Africa. Here the virus is widespread in dog populations and access to affordable vaccines is limited. Children are particularly vulnerable, accounting for around 40% of deaths, and the global economic burden (including medical costs, lost income and psychological impacts) is estimated at about US$8.6 billion annually.

Why are new vaccines are needed?

Rabies vaccines used today work well, but they are difficult and expensive to manufacture, which can limit supplies in places where they are needed most. This has encouraged researchers to explore new types of vaccines that could be produced more easily and at lower cost.

How does the new vaccine work?

Our vaccine uses self‑amplifying RNA containing instructions for producing a key rabies virus protein. This protein stimulates the immune system to generate antibodies. Because the vaccine contains only this protein and not the whole virus, there is no risk of contracting rabies from it. The RNA briefly copies itself inside the muscle, allowing smaller doses to be used. It naturally breaks down within hours to days. A similar RNA platform was previously evaluated in the COVAC‑1 COVID‑19 study (https://www.imperial.ac.uk/covid-19-vaccine-trial/), which involved more than 200 participants and demonstrated a favourable safety profile.

What might the side effects be?

Side effects are expected to resemble those seen with other RNA vaccines. Common reactions include pain, redness or swelling at the injection site, as well as fever, chills, headache, tiredness or muscle aches. These typically resolve within a few days. Less common effects may include stomach discomfort, swollen lymph nodes or mild allergic reactions. 

If you are interested in taking part

Individuals who meet the eligibility criteria and are interested in contributing to this important research are welcome to contact the study team at Chelsea and Westminster Hospital quoting ‘RAB-Vac’ by email: chelwest.crfvaccines@nhs.net or telephone: 02033155601.

 You will be paid up to £2800 for your time, travel and inconvenience.