NCT# stands for National Clinical Trial number. This is a unique identification code given to each clinical trial registered on ClinicalTrials.gov. The format is "NCT" followed by an 8-digit number (for example, NCT00000419). Also called the ClinicalTrials.gov identifier.
As a parent, you know the danger that respiratory syncytial virus (RSV) can pose for your little one. Pfizer’s RSV vaccine (called ABRYSVO®) was the first vaccine approved for use in pregnancy to help protect newborns against RSV until they are 6 months old.
We’re currently researching if a single dose of our RSV vaccine given during a pregnancy continues to offer protection in subsequent pregnancies. The Marguerite study will help us determine how long protection lasts from the first maternal dose and whether a second dose is needed during later pregnancies.
If you are pregnant, you may be able to join the Marguerite study if you:
We are also enrolling a group of participants who are not currently pregnant that received a dose of Pfizer’s RSV vaccine during a previous pregnancy.
These are not the only qualifications needed to be in this study. Our study team will be glad to give you all the details to help you decide if the study is right for you.
Condition
Respiratory syncytial virus (RSV)
Vaccination status
Received a dose of Pfizer’s RSV vaccine during a previous pregnancy
Each clinical trial has its own guidelines for who can participate, called eligibility criteria. However, only the research study staff can determine if you qualify to enroll in the study.
If you are eligible and choose to join this study, the visit schedule will vary depending on whether you are pregnant. The research team will explain more about what will happen during the study, including potential benefits and risks, and answer any questions you may have. Participation is completely voluntary, and you can leave the study at any time.
Pregnant Participants and Their Babies
Non-Pregnant Participants
Visit schedule for pregnant participants
A total of 8-9 study visits over about 7-10 months
Visit schedule for non-pregnant participants
A total of 2 study visits over about 2 days
Study-related costs
No cost to participate, and you will be paid for your time in the study
Respiratory syncytial virus (RSV for short) is a serious risk to millions of babies every year. It can lead to symptoms such as:
Babies are more likely to get very sick or be hospitalized with RSV than older children and adults. Those younger than 6 months are the most vulnerable, making up more than half of all RSV-related deaths in hospitals.1 RSV also causes a significant number of illnesses in the first 5 years of life.
Fortunately, there are now maternal vaccines available that can help to prevent serious RSV illness in babies after they are born.
References:
1. Li Y, Wang X, Blau DM, et al. Global, regional, and national disease burden estimates of acute lower respiratory infections due to respiratory syncytial virus in children younger than 5 years in 2019: a systematic analysis. Lancet. 2022;399(10340):2047-2064.
This short video explains what will happen during the Marguerite study to help you decide if joining is right for you and your baby.
It’s important to have vaccines that can prevent infection and illness for all babies. To develop better vaccines for everyone, we need families of all backgrounds to get involved in vaccine research.
Taking part in this study may help improve vaccine protection not only for your baby, but also other babies in the future. Thank you again for considering this clinical trial.
Clinical trials can lead to life-saving vaccines, but they can’t happen without you.
RSV is a risk to millions of babies every year. In a previous study, researchers found that Pfizer’s maternal RSV vaccine was able to prevent serious RSV disease in newborns. Now, we’re evaluating a second dose for expecting mothers who already received the RSV vaccine in their last pregnancy.
Pfizer’s maternal RSV vaccine has been approved to protect newborns after their parent receives 1 dose of the vaccine while pregnant. Additional research is needed to understand if the first dose offers protection for the next baby against serious RSV infection or if another dose will be needed. The Marguerite study will help decide if parents should receive another dose of the RSV vaccine when they are pregnant again.
f you are pregnant and meet the requirements for the study, you will be enrolled into 1 of 2 vaccination groups. All participants in the first group will receive the study vaccine. In the second group, half of participants will receive the study vaccine and half will receive placebo. The placebo looks like the study vaccine but contains no active ingredients. The study team will let you know if you are part of group 1 or group 2 prior to receiving your study vaccination.
As with any vaccine, local reactions at the injection site can be common – such as redness, swelling, or pain. There is also potential for other symptoms like a mild fever or fatigue. The known side effects will be further explained in the informed consent document and discussed with you by the study doctor before you consider joining the study. If there is any new information that we learn about the study vaccine during the clinical trial, the study doctor will share that with you as well.
