RecruitingPhase IIInterventional

A study to test if LACTIN-V, a type of probiotic made from a specific bacteria (Lactobacillus crispatus CTV-05), is safe and effective in lowering the chances of preterm labour in women who are considered at high risk for giving birth early

This study aims to find out if a special probiotic, LACTIN-V, can prevent early births (preterm labour) in women known to be at higher risk. Preterm birth, especially before 34 weeks, can be very serious for newborns. Evidence shows that certain bacteria in the vagina can affect this risk. LACTIN-V contains a 'good' bacteria called Lactobacillus crispatus CTV-05, which has been linked to a lower chance of early birth. Researchers want to see if giving this probiotic during pregnancy can reduce the number of early births. Women who have had a preterm birth before will be invited to take part. Half will receive LACTIN-V, and the other half will get an inactive substance, to compare the results.

At a glance

Status

Recruiting

Phase

Phase II

Sponsor

Imperial College London

Enrolment target

360

Start

13 Apr 2026

Estimated completion

30 Apr 2027

Preterm labour

What is this study about?

This study is looking into ways to prevent babies from being born too early, which doctors call preterm labour. When a baby is born before 37 weeks of pregnancy, it's called a preterm birth. An even earlier birth, before 34 weeks, can cause serious health problems for the baby, and in some sad cases, can lead to a baby not surviving. Finding ways to reduce or prevent preterm births is very important for the health of both mothers and babies.

We know that the types of natural bacteria living inside a woman's vagina during pregnancy can affect the risk of preterm birth. Having plenty of 'good' bacteria, especially one called Lactobacillus crispatus, seems to lower this risk. On the other hand, if there are different types of bacteria, or not enough of these good bacteria, the risk might go up. LACTIN-V is a special probiotic that contains Lactobacillus crispatus CTV-05. Previous research has shown that when LACTIN-V is used during pregnancy, this good bacteria can grow in the vagina, sometimes replacing less helpful bacteria, and stay there throughout the pregnancy.

The main goal of this study is to see if using LACTIN-V can actually reduce the chances of preterm birth in women who are at a higher risk. By understanding this, doctors hope to find new and safe ways to help more babies be born full-term and healthy. Participants will be carefully monitored, and the study will compare LACTIN-V with a dummy treatment to see if it makes a real difference.

Key takeaways

Aims to reduce preterm birth risk in high-risk women.
Tests a probiotic (LACTIN-V) containing 'good' bacteria.
Participants will be randomly assigned to LACTIN-V or a dummy treatment.
Participation involves using the product and some extra tests at routine appointments.
Potential benefits for future women, but no guaranteed direct benefit for you.
Risks are considered low, mainly minor discomforts from tests.

Who may be eligible?

This study is looking for women who are pregnant with one baby and are between 12 and 16 weeks pregnant. You might be able to join if you have been identified as having a higher chance of preterm labour because you've had a baby born early before, or you've had a miscarriage late in a previous pregnancy. You'll need to be attending a special clinic in an NHS hospital that focuses on preventing preterm birth.

There are also some reasons why you might not be able to join the study. For example, if you are living with HIV, are under 17 years old, are expecting twins or more, or if you know you are allergic to any part of the LACTIN-V product. You also can't take part if you're already in another research study that involves a treatment, if your baby has certain known health conditions, or if you have a medical condition that needs you to take antibiotics regularly during the study. The study team will check all these details to make sure it's safe for you to take part.

Could this study suit you?

Answer these quick questions to see if you may be eligible. This is a guide only — the research team makes the final call.

Are you pregnant with one baby?
Are you between 12 and 16 weeks pregnant?
Have you had a previous preterm birth or late miscarriage?
Do you attend a preterm birth prevention clinic at an NHS hospital?
Are you able to give your consent in writing?
Do you have no known allergies to the study product ingredients?

Answer every question to see your result.

What does participation involve?

If you join the study, you'll be put into one of two groups by chance: one group will receive LACTIN-V, and the other will get a 'dummy' product (a placebo) that looks the same but contains no active ingredients. Neither you nor your doctors will know which one you are receiving. You'll apply the product into your vagina during your pregnancy.

Throughout the study, the research team will take occasional vaginal swab samples and blood tests. These tests help them understand how the product might affect the bacteria in your vagina and link it to your risk of preterm birth. Most of these extra tests will happen at your regular ultrasound or postnatal check-ups, so you won't need many additional visits. You might have some scans (transvaginal ultrasound) as part of your care, which will be done by trained staff to ensure comfort. The study is expected to run until December 2027 and aims to recruit participants from four hospitals in London.

Potential risks and benefits

There is no guarantee that taking part in this study will directly benefit you, as we are still testing if LACTIN-V works. However, the information gained from this study could help future pregnant women reduce their risk of preterm birth. The known risks from LACTIN-V are considered low. In previous studies, it was well-tolerated, with very few side effects, mainly some short-term vaginal discharge. Since it's applied locally, no effects on your whole body are expected. You might feel a little discomfort when samples (like vaginal swabs or blood tests) are taken, or if you get a small bruise from a blood test. It's also possible to feel worried or anxious if regular scans show an increased risk of early birth. You are free to withdraw from the study at any time without affecting your medical care.

Locations (4)

St Mary's Hospital
Approximate
London, England
Queen Charlotte's Hospital
Approximate
London, England
Uclh
Approximate
London, England
Chelsea and Westminster Hospital
Approximate
London, England

Common questions

What is preterm labour?

Preterm labour is when a baby is born before 37 weeks of pregnancy. Babies born very early (before 34 weeks) can face serious health challenges.

What is LACTIN-V?

LACTIN-V is a probiotic, which means it contains 'good' bacteria, specifically Lactobacillus crispatus CTV-05. It's being tested to see if it can help prevent early births.

Will I know if I'm getting LACTIN-V or a dummy treatment?

No, neither you nor your doctors will know if you're getting LACTIN-V or an inactive dummy treatment. This is to make sure the results are fair and accurate.

What are the main things I'll have to do if I join?

You'll apply the study product, and have some vaginal swabs and blood tests during your regular pregnancy appointments. This helps researchers understand the effects.

Can I leave the study at any time?

Yes, you are free to leave the study at any point, and your decision will not affect the medical care you receive.

How to find out more

Imperial Clinical Trials Unit

flip2@imperial.ac.uk - Official trial record

Always speak to your GP or specialist before deciding to take part in a study.