Sixty patients with symptomatic single-level lumbar disc degeneration were randomized to receive high-dose disc progenitor cells (n=20), low-dose cells (n=20), vehicle (n=10), or placebo (n=10). The primary outcome of interest was a ≥30% improvement in visual analog scale (VAS) pain score at 52 weeks. Secondary outcomes included changes in Oswestry Disability Index (ODI), EQ-5D quality of life score, and MRI-assessed disc volume. Outcomes were assessed up to 104 weeks. Overall, the results of the study revealed that only the high-dose group showed a sustained, statistically significant improvement in pain, function, quality of life, and disc volume, with benefits maintained up to two years. These findings suggest high-dose disc progenitor cell therapy is a safe and effective non-surgical treatment for early-to-moderate lumbar disc degeneration.