Ongoing, recruitingTherapeutic confirmatory (Phase III)Interventional

A Phase 3, Randomized, Crossover, Open-Label, Active-Controlled Study of Sepiapterin versus Sapropterin in Participants With Phenylketonuria ≥2 years of Age

This research study is investigating a new medication called sepiapterin for adults aged 18 and older who have a genetic condition called phenylketonuria, or PKU. PKU means your body can't break down a substance called phenylalanine properly, which can build up and cause health problems if not managed. The study aims to find out if sepiapterin is effective at lowering phenylalanine levels in the blood, and how it compares to an already available medicine called sapropterin (also known as Kuvan). Participants will take both medicines at different times during the study to allow doctors to directly compare their effects. Researchers will carefully check blood phenylalanine levels as the main way to see if the new medicine works, and they'll also monitor for any side effects to make sure it's safe.

At a glance

Status

Ongoing, recruiting

Phase

Therapeutic confirmatory (Phase III)

Sponsor

PTC Therapeutics Inc.

Enrolment target

119

Start

15 Apr 2024

Phenylketonuria

What is this study about?

This study is about an important health condition called Phenylketonuria, or PKU for short. PKU is a rare condition that people are born with, where their body can't properly process a part of protein called phenylalanine. If too much phenylalanine builds up in the blood, it can cause serious health problems, especially affecting the brain. People with PKU usually need to follow a special diet and sometimes take medication to keep their phenylalanine levels in a safe range.

In this study, researchers are looking at a new medicine called sepiapterin. They want to see how well it works to lower phenylalanine levels in the blood and if it's a good alternative or improvement to an existing medicine, sapropterin (which you might know as Kuvan). The study is designed so that participants will try both medicines during different periods, allowing doctors to directly compare how each one affects their phenylalanine levels. This type of study, where you try both treatments, is often called a 'crossover' study.

This is a 'Phase 3' study, which means it's one of the final steps before a new medicine might become widely available. Doctors are keen to understand if sepiapterin can help people with PKU manage their condition more effectively and safely. By taking part, people could help bring a new treatment option to others living with PKU.

Key takeaways

This study evaluates a new PKU medicine, sepiapterin, against an existing one.
It's for adults (18+) with Phenylketonuria (PKU).
Participation involves taking blood tests and having regular health checks.
You will receive both medicines at different times during the study.
The main goal is to see how well the new medicine lowers phenylalanine levels.

Who may be eligible?

To be able to join this study, participants must be at least 18 years old. Both men and women are welcome to take part.

It's important to have phenylketonuria (PKU) to be considered for this study. The study focuses specifically on this condition and how new treatments might help managing it. Researchers will also check your current health and medical history to make sure the study is a safe and suitable option for you.

Sometimes, other health conditions or taking certain medications might mean you can't join a study, even if you meet the main criteria. This is always to protect your safety and ensure the study results are as clear as possible. A doctor involved in the study will discuss all the requirements with you.

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 18 years old or older?
Do you have a diagnosis of Phenylketonuria (PKU)?
Are you able to attend regular clinic appointments?
Are you willing to potentially take a new medication that is still under investigation?

Answer every question to see your result.

What does participation involve?

If you decide to take part in this study, you would first have a screening visit to make sure you're a good fit. After that, the study involves two main treatment periods where you'll take either sepiapterin or sapropterin. You'll switch between the two medicines, so everyone gets a chance to try both and we can compare them directly.

During each treatment period, you'll have regular visits to the clinic. At these visits, doctors and nurses will take blood samples to measure your phenylalanine levels, perform physical check-ups, measure your blood pressure and heart rate, and do other routine tests like an ECG (a test for your heart) and standard blood tests. These checks are important to see how the medicine is working and to monitor your general health and safety.

The specific duration of the treatment periods and follow-up will be explained by the study team, but generally, studies like this involve several weeks of treatment with each medicine, plus follow-up appointments. The total duration of your participation, from start to finish, will be clearly outlined.

Potential risks and benefits

Taking part in this study could offer some potential benefits, such as receiving expert medical care and close monitoring of your PKU. You might also have access to a new medicine (sepiapterin) that isn't yet widely available, which could potentially help manage your phenylalanine levels. However, as with any medication, there are always potential risks; you might experience side effects from the study medicines, which will be carefully monitored. The study team will explain all known potential side effects. Please remember, participating is entirely voluntary, and you have the right to withdraw from the study at any time, for any reason, without it affecting your usual medical care.

Locations (9)

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

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Unverified
Denmark
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Unverified
Spain
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Unverified
Italy
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Unverified
France
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Unverified
Germany
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Unverified
Slovenia
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Unverified
Czechia
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Unverified
Poland
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Unverified
Netherlands

Common questions

What is Phenylketonuria (PKU)?

PKU is a rare inherited condition where your body can't break down a substance called phenylalanine, which is found in many foods. Too much phenylalanine can lead to health problems.

What is the new medicine being tested?

The new medicine is called sepiapterin. It's being compared to an existing medicine, sapropterin (Kuvan), to see if it's effective at lowering phenylalanine levels for people with PKU.

Will I have to stop my current PKU treatment?

The study team will discuss your current treatment and whether any changes would be needed for you to participate safely. This will be explained in detail before you decide to join.

What does 'crossover study' mean?

It means you will receive both medicines being tested (sepiapterin and sapropterin) at different times during the study. This helps compare them directly within the same person.

Can I leave the study if I change my mind?

Yes, your participation is completely voluntary. You can choose to leave the study at any time, for any reason, without it affecting your medical care.