Condition

Phenylketonuria clinical trials and research

• 11Clinical trials
• 9NIH research projects
• 14Countries

Newest Phenylketonuria clinical trials

All recruiting trials (11)

• Impact of a Phenylalanine-Restricted Diet on Gut Health in Children with PKU

  This study looks at how a Phe-restricted diet, with or without sapropterin or sepiapterin, might affect gut health in kids with PKU.

  Recruiting Birmingham Women's and Children's NHS Foundation Trust · Birmingham · NCT07728032

• How Repinatrabit is processed in adults with liver or kidney impairment versus normal function

  This study tests how Repinatrabit is handled by the body in adults with moderate liver impairment or severe kidney impairment compared to adults with normal liver function.

  Recruiting Phase 1 Otsuka Pharmaceutical Development & Commercialization, Inc. · Miami, Florida · NCT07713758

• Eating disorders in people with phenylketonuria

  This study looks at whether eating disorders and BMI issues are more common in people with phenylketonuria who are followed at a French hospital.

  Recruiting Central Hospital, Nancy, France · Nancy · NCT07698743

• GenSci144 tablets early-dose study for phenylketonuria treatment

  This early-phase trial tests a single dose of GenSci144 tablets in healthy adults to see if it is safe and tolerable, while also looking at how the body processes the drug.

  Recruiting Phase 1 Changchun GeneScience Pharmaceutical Co., Ltd. · Jinan, Shandong · NCT07685210

• Immune Modulation During Palynziq Treatment in Adults

  This study tests whether adding low-dose methotrexate can help people with PKU tolerate Palynziq better and achieve better blood levels of phenylalanine.

  Recruiting at 10 sites Phase 4 BioMarin Pharmaceutical · Los Angeles, California and 11 other locations · NCT07477691

• AG-181 safety and tolerability in people with phenylketonuria

  This trial will test AG-181 for safety and tolerability in people with PKU who have high blood phenylalanine and at least one R408W PAH mutation.

  Recruiting at 5 sites Phase 1 Agios Pharmaceuticals, Inc. · Indianapolis, Indiana and 4 other locations · NCT07241234

• JNT-517 treatment for adults with phenylketonuria (PKU)

  This study will test whether taking JNT-517 pills twice daily lowers high blood phenylalanine and is safe for adults with PKU.

  Recruiting at 26 sites Phase 3 Otsuka Pharmaceutical Development & Commercialization, Inc. · Los Angeles, California and 25 other locations · NCT06971731

• GMP-based powdered protein substitutes for phenylketonuria and tyrosinemia

  This will test whether GMP-based powdered protein substitutes can replace regular amino-acid formulas for people with phenylketonuria or tyrosinemia to improve taste and diet adherence while keeping blood amino acids stable.

  Recruiting Nutricia UK Ltd · Birmingham · NCT06941532

• Evaluating sepiapterin for children with phenylketonuria

  This study is testing if sepiapterin can help children with phenylketonuria keep their brain function and development healthy over time.

  Recruiting at 14 sites Phase 3 PTC Therapeutics · Indianapolis, Indiana and 13 other locations · NCT06302348

• Understanding how families react when PKU is announced after newborn screening

  This study tests how parents and clinicians experience the PKU announcement after newborn screening and how to improve the support given at diagnosis.

  Recruiting Assistance Publique - Hôpitaux de Paris · Paris · NCT06289348

• Educational and nutritional support for women with Phenylketonuria during pregnancy

  This study tests whether a special camp that offers education and support can help women with PKU or MSUD have healthier pregnancies and improve their overall well-being.

  Recruiting Emory University · Atlanta, Georgia · NCT01659749

NIH-funded research (9)

Early-stage science funded by the US National Institutes of Health. Most of these projects don't enroll patients, but they show what is being worked on.

• LNP-based adenine base editing for PKU and urea cycle disorders

  A front-line, patient-focused research project aims to develop safe gene-editing therapies that could lessen or correct the biochemical problems in PKU and related urea cycle disorders.

  NIH research Children's Hosp of Philadelphia · Philadelphia, United States · NIH-11421632

• PKU: a new gene-editing treatment for a common PAH mutation

  A new therapy using lipid nanoparticles to correct a common PKU mutation could reduce the need for strict diets and dangerous enzyme injections.

  NIH research Children's Hosp of Philadelphia · Philadelphia, United States · NIH-11389354

• A new gene-editing approach to treat phenylketonuria (PKU)

  A medical research project is testing a gene-editing strategy using AAV-delivered CRISPR tools to correct PAH gene defects in PKU patients.

  NIH research University of Pennsylvania · Philadelphia, United States · NIH-11332257

• Phenylalanine and brain function in PKU carriers and non-carriers

  We’re exploring how a single elevated nutrient (phenylalanine) affects thinking and brain function in adults who carry a PKU gene variant compared with those who don’t.

  NIH research University of Missouri-Columbia · Columbia, United States · NIH-11326741

• Gene-editing treatment for phenylketonuria caused by the P281L PAH mutation

  A lipid nanoparticle-delivered adenine base editor to correct the P281L PAH mutation in people with phenylketonuria.

  NIH research Children's Hosp of Philadelphia · Philadelphia, United States · NIH-11145249

• Using gene editing to treat phenylketonuria

  This study is exploring a new way to use gene editing to help people with phenylketonuria (PKU) by fixing the genetic issues that cause the condition, aiming to offer a better treatment than the current strict diets and medications.

  NIH research University of Pennsylvania · Philadelphia, United States · NIH-11103130

• Investigating how elevated phenylalanine affects brain and cognitive function in adults who carry the PKU gene.

  This study is looking at how higher levels of phenylalanine (Phe) might affect thinking and brain function in adults who carry the PKU gene but don’t have the condition, to help us understand if they might face any challenges related to Phe.

  NIH research University of Missouri-Columbia · Columbia, United States · NIH-11057253

• Understanding how long noncoding RNAs affect phenylketonuria

  This study is looking at how certain molecules in our genes, called lncRNAs, might help find new ways to treat phenylketonuria (PKU), a condition caused by changes in a specific gene, and it could lead to better options for people living with PKU.

  NIH research University of Tx Md Anderson Can Ctr · Houston, United States · NIH-11015069

• A new treatment approach for phenylketonuria (PKU).

  This study is working on a new treatment for people with phenylketonuria (PKU) who have a specific gene mutation, aiming to make managing the condition easier and safer than current methods, and they hope to start testing it in patients soon.

  NIH research Children's Hosp of Philadelphia · Philadelphia, United States · NIH-10896260

Related topics

Quick answers

How many Phenylketonuria clinical trials are recruiting right now?

11, as of November 12, 2026. We update this list each time we refresh our data from ClinicalTrials.gov.

Where are these trials running?

In 14 countries. The most sites are in United States (6 trials), France (4 trials), Poland (3 trials), United Kingdom (3 trials), Australia (2 trials). Each study page lists its sites and which ones are recruiting.

What phases are they in?

Phase 1: 3, Phase 3: 2, Phase 4: 1. Trials with no phase listed are usually device, behavioural or observational studies.

How do I join one?

Open a study, check the "Is this trial a fit for you?" section, then contact the study team listed on the page. They will ask a few screening questions. Asking is free and does not commit you to anything. Talk it over with your doctor first.

Find the studies that fit you

A list is a starting point. Tell us your situation in your own words and we'll rank the studies that match and explain why. It's free and needs no account.

Describe your situation →