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Recruiting Phase 4 NCT07477691

NCT07477691 Immune Modulation During Palynziq® Treatment in Adults (IMPALA)

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Clinical Trial Summary
NCT ID NCT07477691
Status Recruiting
Phase Phase 4
Sponsor BioMarin Pharmaceutical
Condition Phenylketonuria
Study Type INTERVENTIONAL
Enrollment 12 participants
Start Date 2026-05-29
Primary Completion 2027-09-30

Eligibility & Interventions

Sex All sexes
Min Age 18 Years
Max Age 65 Years
Study Type INTERVENTIONAL
Interventions
PegvaliaseMethotrexate

Eligibility Fast-Check

Enter your details for a quick preliminary check. This does not replace medical advice.

What to Expect as a Participant

You will actively receive the study intervention — which may be a drug, biologic, device, or procedure.

Phase 4 studies follow an already-approved treatment in real-world conditions to monitor long-term safety and effectiveness.

This trial targets 12 participants in total. It began in 2026-05-29 with a primary completion date of 2027-09-30.

⚠ This information is for research awareness only. Always consult your physician before joining any clinical trial. Participation is voluntary and you may withdraw at any time.

Brief Summary

Study 165-401 is a Phase 4, open-label study designed to examine the concomitant use of methotrexate (MTX) to suppress immune responses to Palynziq and improve tolerability and efficacy in adults with PKU.

Eligibility Criteria

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

Contact & Investigator

Central Contact

Trial Specialist

✉ medinfo@bmrn.com

📞 1-800-983-4587

Principal Investigator

Medical Director, MD

STUDY DIRECTOR

BioMarin Pharmaceutical

Frequently Asked Questions

Who can join the NCT07477691 clinical trial?

This trial is open to participants of all sexes, aged 18 Years or older, up to 65 Years, studying Phenylketonuria. Full inclusion and exclusion criteria are listed in the Eligibility Criteria section. Always confirm your eligibility with the research team before applying.

What phase is the NCT07477691 trial and what does that mean for participants?

Phase 4 studies are conducted after a treatment has been approved. They monitor long-term safety and real-world effectiveness in a broader patient population.

Is NCT07477691 currently recruiting?

Yes, NCT07477691 is actively recruiting participants. Contact the research team at medinfo@bmrn.com for enrollment information.

Where is the NCT07477691 trial being conducted?

This trial is being conducted at Los Angeles, United States, Aurora, United States, Tampa, United States, Chicago, United States and 8 additional locations.

Who is sponsoring the NCT07477691 clinical trial?

NCT07477691 is sponsored by BioMarin Pharmaceutical. The principal investigator is Medical Director, MD at BioMarin Pharmaceutical. The trial plans to enroll 12 participants.

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ClinicalMetric — Independent clinical trial intelligence platform. Not affiliated with NIH, ClinicalTrials.gov, the U.S. FDA, or any pharmaceutical company, hospital, or clinical research organization. Trial data is sourced from ClinicalTrials.gov for informational purposes only and does not constitute medical advice. Do not make any treatment, enrollment, or health decisions based solely on information found here — always consult a qualified healthcare professional. Full Disclaimer  ·  Last Reviewed: April 2026  ·  Data Methodology