AuthorisedPhase I and Phase II (Integrated)- OtherInterventional

A Phase 1/2, Global, Open-Label, Extension Study to Evaluate the Long-Term Safety and Clinical Activity of mRNA-3927 in Participants Previously Enrolled in the mRNA-3927-P101 Study

This research is an 'extension study' for people living with a rare condition called Propionic Acidemia. It's for those who have already taken part in a previous study testing a new medicine called mRNA-3927. The main goal is to understand how safe the medicine is when taken over a longer time and to see if it continues to help patients manage their condition. Researchers will carefully watch for any side effects, both mild and serious. They will also track how often patients have symptom flare-ups, need to go to hospital, or seek urgent medical help related to their Propionic Acidemia. This helps doctors learn more about the long-term effects of this new treatment.

At a glance

Status

Authorised

Phase

Phase I and Phase II (Integrated)- Other

Sponsor

Moderna Inc.

Enrolment target

Start

23 Feb 2026

Propionic Acidemia

What is this study about?

This study is designed for individuals who have Propionic Acidemia, a rare inherited condition where the body cannot properly break down certain proteins and fats. This can lead to a build-up of harmful substances, causing serious health problems. The new medicine being tested, mRNA-3927, aims to help the body process these substances better. This particular study is an 'extension' of an earlier trial, meaning it's for people who have already started taking mRNA-3927 in a previous study.

Now that the initial study has evaluated the short-term effects, this extension study allows researchers to observe the long-term safety and whether the medicine continues to help manage Propionic Acidemia symptoms over a longer period. This is really important because treatments for long-term health conditions often need to be taken for many years, and doctors need to understand their effects over time.

The main focus of this study is on safety – checking for any side effects and how serious they might be. Researchers will also be looking at how often people experience health problems or need medical attention related to their Propionic Acidemia, such as emergency visits or hospital stays. By collecting this information, doctors hope to gain a much clearer picture of how mRNA-3927 works as a long-term treatment option for Propionic Acidemia.

Key takeaways

This study is for adults with Propionic Acidemia who were in a previous trial.
It aims to check the long-term safety and effects of mRNA-3927.
Researchers will closely monitor for any side effects and how often patients experience health issues related to their condition.
Participation involves ongoing clinic visits and health assessments.
You have the right to leave the study at any time.

Who may be eligible?

To be considered for this study, you must have already taken part in the previous study for mRNA-3927 (called mRNA-3927-P101). This means you would have already received the study medicine.

Participants must be at least 18 years old. There is no upper age limit, so adults of any age can potentially join, provided they meet all other criteria. Both men and women are welcome to participate.

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.

I have Propionic Acidemia.
I have previously participated in the mRNA-3927-P101 study.
I am 18 years old or older.

Answer every question to see your result.

What does participation involve?

If you join this study, you will continue to receive the study medicine, mRNA-3927, as before. You will have regular visits to the clinic so the study team can monitor your health, check for any side effects, and see how you are responding to the treatment. These visits will likely include physical examinations, blood tests, and discussions about any symptoms or medical events you experience.

The study team will carefully record any health problems, whether they seem related to the medicine or not. They will also track how often you might need urgent medical care or hospital stays due to your Propionic Acidemia. The total length of your participation will depend on the study design and your individual health, but the aim is to follow participants over a longer period. You will be given a detailed schedule of visits and procedures if you decide to take part.

Potential risks and benefits

A potential benefit of joining this study is continuing to receive mRNA-3927, which may continue to help manage your Propionic Acidemia. Your health will also be closely monitored by a team of medical professionals. However, as with any medicine, there are potential risks, including side effects from mRNA-3927. These will be thoroughly explained to you, and the study team will monitor you closely for them. You have the right to withdraw from the study at any time, for any reason, without it affecting your usual medical care.

Locations (3)

Some site locations are approximate. We're improving this — please verify with the trial team before travelling.

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Unverified
Spain
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Unverified
Netherlands
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Unverified
France

Common questions

What is Propionic Acidemia?

Propionic Acidemia is a rare inherited condition where your body can't properly break down specific proteins and fats, leading to harmful substances building up.

What is mRNA-3927?

mRNA-3927 is a new medicine being tested in a clinical trial to help individuals with Propionic Acidemia manage their condition.

Why is this study called an 'extension' study?

It's an extension study because it's for people who have already been in a previous study for mRNA-3927, allowing doctors to look at the medicine's effects over a longer time.

What are 'side effects'?

Side effects are any unwanted or unexpected effects that a medicine might have on your body. The study team will carefully monitor these.

Will I have to pay to be in this study?

Usually, clinical trials cover the costs of the study medicine and any study-related tests or visits. This will be confirmed to you by the study team.