Clinical Exploration Study of YOLT-203 in the Treatment of Type 1 Primary Hyperoxaluria (PH1)
This study is a single-arm, open-label, single-dose, dose-escalation, and dose-expansion trial, aiming to assess the safety and tolerability of YOLT-203 in Chinese patients with Primary Hyperoxaluria Type 1 (PH1), and to preliminarily evaluate the effect of a single dose of YOLT-203 on plasma oxalate levels. In this study, the maximum duration of the screening period is 60 days, with the treatment day being Day 1 (D1), and the safety follow-up period extending to the 52nd week after dosing. Additionally, in the dose-escalation phase, after the first dose cohort, investigators will conduct a comprehensive evaluation based on safety, pharmacokinetic (PK), and pharmacodynamic (PD) data, and following discussion at the Safety Review Committee (SRC) meeting, subjects may voluntarily receive a second administration of the study drug at an effective dose level. After the completion of the main study, subjects will undergo long-term follow-up. In accordance with the requirements of the Technical Guidance for Clinical Research on Long-term Follow-up of Gene Therapy Products (Trial) issued by the Center for Drug Evaluation (CDE), long-term follow-up will be conducted for up to 15 years after dosing.
• The age is ≥ 2 years old at the time of signing the informed consent.
• Have AGXT gene mutations and be diagnosed with primary hyperoxaluria (PH1); eGFR ≥ 30 ml/min/1.73m2.
• At least 2 times of 24-hour urinary oxalate excretion ≥ 0.7 mmol/1.73m2/day or the ratio of urinary oxalate to creatinine in a single urine collection must be higher than the upper limit of normal (ULN) for the corresponding age.
• If treated with vitamin B6, the treatment has been stable for 90 days before enrollment in the study and is willing to maintain the stable treatment plan unchanged during the study.
• The patient himself/herself or the guardian voluntarily signs the informed consent.