YolTech Therapeutics Announces Positive Clinical Data for YOLT-203, an In Vivo Gene Editing Therapy for Primary Hyperoxaluria Type 1 (PH1)

SHANGHAI, Feb. 25, 2025 /PRNewswire/ -- YolTech Therapeutics, a clinical-stage in vivo gene editing company committed to pioneering the next generation of precision genetic medicines, today reported positive results from the ongoing investigator-initiated trial (IIT) of YOLT-203 in patients with primary hyperoxaluria type 1 (PH1) (ClinicalTrials.gov ID: NCT06511349), with data demonstrating excellent safety and pharmacodynamics profiles and the potential of YOLT-203 to effectively normalize urinary oxalate levels in PH1 patients. YOLT-203 is the first in vivo gene-editing therapy to show positive clinical data for PH1.

YOLT-203 is an investigational in vivo gene-editing therapy designed to be a one-time life-long cure for PH1, a rare genetic disorder that causes kidney stone accumulation and potentially kidney failure. YOLT-203 has the potential to reduce the oxalate overproduction in PH1 patients by deactivating glycolate oxidase (GO), an enzyme encoded by HAO1 gene and suppressing the synthesis of oxalate precursors. YOLT-203 intends to edit the HAO1 gene in hepatocytes by YolTech Therapeutics' proprietary CRISPR/Cas gene-editing system YolCas12HF delivered via proprietary lipid nanoparticles (LNPs).

In August 2024, YOLT-203 was the first investigational in vivo gene-editing therapy to enter clinical trial for PH1. The IIT of YOLT-203 was to evaluate the efficacy, safety, pharmacodynamics of YOLT-203. As of January 2025, seven PH1 patients were enrolled in YOLT-203-IIT and dosed with YOLT-203 via intravenous infusion. For patients received the high dose, nearly 70% reduction of 24-hour urinary oxalate levels was observed and sustained through the 16-week primary observation period. At all dose levels, YOLT-203 was well-tolerated. There have been no serious adverse events (SAEs), treatment discontinuations or patient withdrawals.

In September 2024, YOLT-203 received dual FDA designations, Orphan Drug Designation (ODD) and Rare Pediatric Disease Designation (RPDD).

Dr. Yuxuan Wu, Founder and CEO of YolTech Therapeutics, stated, "The clinical results of YOLT-203 represents a breakthrough in the field of in vivo gene-editing therapies. In this clinical trial, we have proven the potential efficacy of our proprietary gene-editing system YolCas12HF, a system with enhanced editing precision and efficiency compared to conventional platforms and the ability to avoid legal complexities of the ongoing CRISPR/Cas9 patent disputes. Most importantly, it marks the first full-cycle innovation by a Chinese team, spanning from discovery, optimization to clinical translation of next-generation in vivo gene-editing drugs. We fully understand the urgent need for patients with rare diseases to have a treatment addressing the root of their diseases. Exemplified by YOLT-203, we believe one-time treatments for lifelong cure will redefine the standard of care for rare diseases globally."

About Primary Hyperoxaluria (PH)
Primary Hyperoxaluria (PH) is a rare autosomal recessive genetic disorder caused by enzyme deficiencies in hepatic oxalate metabolism, leading to excessive oxalate production and systemic oxalate deposition. PH1, the most common subtype, is triggered by AGXT gene mutations and typically manifests in childhood. Patients often present with kidney stones, nephrocalcinosis, renal insufficiency, and oxalate deposition in other organs. Severe cases progress to end-stage renal disease (ESRD), requiring dialysis, kidney transplantation, or combined liver-kidney transplantation. PH primarily affects children, with symptoms usually appearing between ages 0–3. Without effective intervention, most patients develop ESRD during adolescence, posing life-threatening risks. The estimated prevalence of PH is 1 in 58,000, affecting approximately 10,000 individuals in the U.S. and EU.

About YolTech
YolTech Therapeutics is a clinical-stage in vivo gene editing company committed to pioneering the next generation of precision genetic medicines. Our approach combines innovative gene editing technologies with an advanced lipid nanoparticle (LNP) delivery system, creating a versatile platform designed to address a wide range of serious diseases. Central to our mission is the development of internal capabilities, including end-to-end manufacturing, to ensure the highest standards of quality and scalability. Our lead candidate, targeting ATTR, marks a significant milestone as China's first LNP-mediated in vivo gene editing therapy to enter clinical development. With promising early clinical outcomes, YolTech is also advancing therapies for familial hypercholesterolemia (FH) and primary hyperoxaluria type 1 (PH1). As a company dedicated to transforming the treatment landscape, YolTech continues to push the boundaries of what is possible in gene editing.

For more information, please visit: www.yoltx.com 

SOURCE YolTech Therapeutics