A Phase I Multicenter Open-label Dose-escalation Study of Safety, Tolerability, PK/PD and Immunogenicity of Single/Multiple Subcutaneous PL54 Injection in Adult PKU Patients
The primary objective of this clinical trial is to evaluate the safety and tolerability of single and multiple administrations of PL54 in patients aged 18-55 years. The key questions it aims to answer include: How safe and tolerable is PL54 in PKU patients following single and multiple administrations? Researchers will compare the safety and tolerability profiles between single and multiple dosing regimens to assess PL54. Participants will be required to: Phase Ia (Single Administration): Receive a single subcutaneous injection of PL54 based on body weight. Undergo a 28-day observation period post-injection. Visit the clinic for assessments on: D1 (administration day), D2, D7, D8, D10, D15, D22, and D29. Phase Ib (Multiple Administrations): Receive subcutaneous injections of PL54 every 7 days (4 doses total) based on body weight. Undergo a 35-day observation period after the last injection. Visit the clinic for assessments on: D1 (first administration), D3, D8, D15, D21, D22, D29, D36, D43, and D57 Data to be recorded include: Incidence, severity, seriousness, relationship to PL54 treatment, duration, and outcome of adverse events (AEs). Change from baseline in blood phenylalanine (Phe) concentration.
• Adult patients aged 18 to 55 years, inclusive, regardless of sex.
• Subjects with a prior diagnosis of phenylketonuria (PKU) meeting the following criteria:
‣ Blood Phe concentration ≥600 µmol/L at screening;
⁃ Average blood Phe concentration ≥600 μmol/L within the 12 months prior to screening (with at least two test results available);
⁃ Genetic test report confirming the presence of phenylalanine hydroxylase (PAH) gene defects.
• Ability to maintain dietary stability from 3 days prior to screening through the end of the trial.
• Subjects (including partners) capable of practicing effective contraception during the trial period, with no plans for conception within 3 months after trial completion.
• Voluntarily sign the informed consent form and, in the investigator's judgment, able to comply with all study requirements.