Immune Modulation During Palynziq Treatment in Adults

Is this trial a fit for you?

A plain-English reading of the study's rules. Only the study team can confirm whether you qualify.

What this trial studies

This is a Phase 4, open-label study evaluating the use of methotrexate concurrently with Palynziq in adults with phenylketonuria (PKU). Up to 12 participants are enrolled across two cohorts to see if MTX suppresses immune responses to Palynziq, potentially improving tolerability and efficacy. Cohort A includes Palynziq-naïve individuals with very high phenylalanine levels, while Cohort B includes Palynziq-experienced patients who have uncontrolled Phe despite ongoing Palynziq. MTX is given at 15 mg/week with Palynziq, starting with a tolerability period, and Palynziq dosing follows standard guidelines. Key outcomes focus on safety, tolerability, and changes in PKU-related biomarker responses.

Why it matters

Who can join: the full rules

Inclusion Criteria:

* Adults between 18 and 65 years old
* Have a confirmed diagnosis of phenylketonuria (PKU)
* Are in generally good health based on medical evaluation
* Are willing and medically eligible to receive Palynziq and methotrexate (MTX) Cohort A: Have never taken Palynziq before and are willing to start it during the study Cohort B: Have blood \> 600 μmol/L after taking Palynziq for at least 24 weeks, are on a daily dose of at least 20mg and unable to increase the dose further
* Agree to use required contraception if they or their partner could become pregnant
* Are willing to carry two epinephrine devices at all times during Palynziq treatment

Exclusion Criteria:

* Pregnant, breastfeeding, planning to become pregnant, planning to father a child, or not using effective birth control if applicable
* Have a known severe allergy or hypersensitivity reaction to methotrexate (MTX), Palynziq, or other PEG-containing medications
* Have a serious active infection or a history of severe or recurrent infections
* Have significant medical conditions that may affect safety or participation (such as serious heart, lung, liver, kidney, immune, neurological, psychiatric, or cancer-related conditions)
* Have a history of substance or alcohol abuse within the past 12 months
* Have had an organ transplant or are taking chronic immunosuppressive medications
* Are currently taking medications that are not allowed in the study, including other PKU treatments besides Palynziq
* Are using, or plan to use, injectable PEG-containing medications other than Palynziq during the study
* Have major surgery planned during the study participation period
* Are currently participating in another clinical study involving Palynziq
* In the opinion of the study doctor, are not a suitable candidate for the study or may have difficulty complying with study requirements

Where it's running

• UCLA Dept. of Human Genetics
  Los Angeles, California, United States Recruiting
• Children's Hospital Colorado
  Aurora, Colorado, United States Recruiting
• University Of South Florida Medical Center
  Tampa, Florida, United States Recruiting
• Ann & Robert H. Lurie Children's Hospital of Chicago
  Chicago, Illinois, United States Recruiting
• Indiana University School of Medicine
  Indianapolis, Indiana, United States Recruiting
• University of Minnesota Medical School
  Minneapolis, Minnesota, United States Recruiting

Study contacts

• Study coordinator: Trial Specialist
• Email: medinfo@bmrn.com
• Phone: 1-800-983-4587

Similar studies

Other studies for the same condition or treatment. Recruiting studies are listed first.

• 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

• 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

How to take part

1. Review the eligibility criteria above with your treating physician.
2. Check the official listing on ClinicalTrials.gov for the latest contact details and recruitment status.
3. Contact the study coordinator or principal investigator to ask for pre-screening. Pre-screening is free and never obligates you to enroll.