CompletedPhase IIInterventional

A research study testing NGM120 in pregnant women with severe nausea and vomiting (Hyperemesis Gravidarum)

Hyperemesis gravidarum (HG) is much more severe than typical morning sickness. It can cause constant nausea, frequent vomiting, weight loss, and repeated hospital admissions. Currently, safe and effective treatment options for HG are very limited. This Phase II study, called EMERALD, is testing a new drug named NGM120 to see if it can safely ease severe sickness during pregnancy. The study is open to pregnant women aged 18 to 45 who are between 9 and nearly 17 weeks pregnant with one baby. Participants continue taking their usual sickness medication while attending four hospital visits over 12 days. During the study, each participant receives one dose of NGM120 and one dose of a dummy treatment (placebo), given one week apart. Expert NHS teams will closely monitor both mother and baby throughout the trial to ensure safety.

At a glance

Status

Completed

Phase

Phase II

Sponsor

NGM Biopharmaceuticals, Inc.

Enrolment target

Start

03 Feb 2025

Estimated completion

10 Apr 2026

Hyperemesis gravidarum

What is this study about?

Hyperemesis gravidarum (HG) is a debilitating pregnancy condition that goes far beyond everyday morning sickness. Women with HG often experience constant, overwhelming nausea and persistent vomiting. This can make keeping food and fluids down nearly impossible, frequently leading to severe dehydration, weight loss, and stays in hospital. It can also cause immense emotional distress and may affect the baby's growth.

At present, doctors have few effective treatments to offer, and many existing medicines do not give enough relief. The EMERALD clinical trial is investigating whether a new medicine, an antibody treatment called NGM120, can help. Researchers want to find out if NGM120 is safe for both mother and baby, and whether it can noticeably reduce nausea and help women manage daily life more comfortably.

Because this is an early-stage study, taking part involves careful monitoring by specialist NHS pregnancy teams. Finding a new, targeted treatment for HG could transform future care for thousands of pregnant women who suffer from severe sickness.

Key takeaways

The EMERALD study tests a new medicine (NGM120) to treat severe pregnancy sickness (hyperemesis gravidarum).
Open to women aged 18–45 who are carrying a single baby and are 9 to 16 weeks pregnant.
You do not stop your current sickness medicines; doses must stay the same for 12 days.
Participation involves four hospital visits over 12 days and two injections (one active, one placebo).
Specialist NHS pregnancy teams will closely monitor your health and your baby's progress.

Who may be eligible?

This study is open to pregnant women aged 18 to 45 who are between 9 weeks and just under 17 weeks pregnant. You must be carrying a single baby and experiencing severe nausea and vomiting, which your study doctor will measure using a standard pregnancy sickness score.

To ensure results are clear, you must be happy to keep your current sickness medicines and dosages exactly the same from three days before the study starts until day 12. You will still receive all of your usual supportive care, such as hospital fluids if you need them.

You cannot take part if your sickness is caused by another condition, such as bowel problems or a stomach disorder. You will also not be able to join if you have certain long-term conditions, including uncontrolled diabetes, kidney disease, serious heart conditions, epilepsy, active hepatitis, HIV, or if there are known chromosomal abnormalities with the baby.

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 between 18 and 45 years old?
Are you pregnant with one baby and between 9 and 16 weeks along?
Are you suffering from severe, daily nausea and vomiting?
Are you willing to keep your current sickness medications at the same dose for about two weeks?
Are you free from other major medical conditions, such as kidney disease, epilepsy, or bowel obstructions?

Answer every question to see your result.

What does participation involve?

Taking part in the trial lasts around 12 days and involves four hospital visits. You will not have to stop your normal sickness medicines, but you must agree to keep the doses stable during this period. Over the course of the study, you will receive two injections: one will be the study medicine (NGM120) and the other will be a dummy medicine (placebo), given seven days apart. This allows doctors to compare how you feel with each treatment. At your hospital visits, the medical team will carry out health checks, take blood samples, and closely check on your baby's development. You will also be asked to track your nausea symptoms and daily activities.

Potential risks and benefits

A potential benefit of joining is that your sickness symptoms may improve, although this cannot be guaranteed. Your participation will also help doctors learn more about treating HG, which could benefit pregnant women in the future. The risks include possible side effects from NGM120, such as headaches or temporary discomfort from injections and blood tests. Because the medicine is new, there may also be unforeseen risks to the pregnancy. To protect you and your baby, an independent group of medical experts will continually review safety data. Taking part is entirely voluntary, and you are free to withdraw at any time without your standard NHS maternity care being affected in any way.

Locations (7)

Birmingham Women's and Children's Hospital
City only
Birmingham, England
Rosie Hospital
Approximate
Cambridge, England
Pinderfields Hospital
Approximate
Wakefield, England
Norfolk & Norwich University Hospital
Approximate
Norwich, England
Royal Free Hospital
Approximate
London, England
King's College Hospital
Unverified
London, England
Northwick Park Hospital
Unverified
Harrow, England

Common questions

Will I have to stop taking my usual sickness medicines?

No. You will continue taking your normal prescribed sickness medicines, but you will need to keep the doses unchanged from three days before the study starts until day 12.

What is a placebo?

A placebo is a harmless dummy treatment that looks just like the real medicine but contains no active ingredients. It helps researchers see whether changes in symptoms are truly caused by the study drug.

Will I definitely receive the new medicine?

Yes. This study is designed so that every participant receives one dose of the study medicine and one dose of the placebo, given a week apart in a random order.

How is my baby's health monitored?

Experienced NHS doctors and midwives will conduct regular health checks and scans to keep a close eye on your baby's growth and wellbeing throughout the trial.

What happens if I feel too ill to continue?

You can leave the study at any point. Your decision will not affect the quality of your regular NHS care or your relationship with your healthcare team.

How to find out more

NGM Study Director

EMERALD@ngmbio.com +1-650-727- 8800 Official trial record

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