The Royal Free London is looking for pregnant women to join the RSVoyage trial, a clinical trial for an investigational vaccine that aims to prevent respiratory syncytial virus (RSV) infection in babies.

The purpose of the trial is to evaluate the safety and immune response of a messenger RNA (mRNA) – based investigational vaccine aimed at preventing RSV in babies. An investigational vaccine is a vaccine not yet approved by a country’s regulatory agency.

RSV is a common respiratory virus that infects the lungs and breathing passages and can cause bronchiolitis and other chest infections. Globally in 2019, RSV caused 6.6 million respiratory infections in infants six months of age and younger. Young children are at greater risk for severe RSV infection, especially those under six months of age, because their respiratory and immune systems are not fully developed. 

Who can join? 

This clinical trial is looking for pregnant participants. To join, you must be: 

•    18 to less than 40 years of age 
•    In good health 
•    28 to 36 weeks pregnant at the time of the vaccination visit* 

*You can still contact us if you are earlier than 28 weeks pregnant. 

What to expect 

Participation in the RSVoyage trial will last up to 15 months. This includes up to three months before you give birth and 12 months after you give birth. 

•    You will have approximately eight in-person visits and four phone calls with the clinical trial team. After delivery, these visits and phone calls will include both you and your baby.
•    You will be given one injection in the upper arm 
•    You must complete electronic diary (eDiary) entries for seven days after the injection, starting on and including the day of injection. Once your baby is born, you will complete eDiary entries regularly 
•    Enrolling in this clinical trial is completely your choice. You may stop participating in the trial at any time, and you do not have to give a reason for doing so
•    Qualified participants will receive payment for their trial-related time and travel 

Interested in participating? 

Participating in this clinical trial will help advance research that may potentially change how we protect babies from RSV. 

The trial will be conducted at the Royal Free Hospital but pregnant women planning to give birth at Barnet Hospital can also take part. Participants will be reimbursed for taking part in the trial.

To learn more about the RSVoyage trial, including payment information and how to join, call us on 020 7272 6426 or 07974 388732 or e-mail us at