Juncell Therapeutics’ GC101 TIL Therapy Achieves Primary Endpoint in the Pivotal Phase II Trial for PD-1 Antibody Failed Advanced Melanoma

On June 3, 2026 Shanghai Juncell therapeutics, reported a Late-Breaking Abstract (LBA) oral presentation at the 2026 American Society of Clinical Oncology (ASCO) (Free ASCO Whitepaper) Annual Meeting, Professor Lu Si from Peking University Cancer Hospital presented the results of a Pivotal Phase 2 clinical study (MIZAR-003) conducted in China evaluating the efficacy and safety of GC101 TIL therapy (Nolgileucel), developed by Shanghai Juncell Therapeutics Co., Ltd. for PD-1 antibody failed patients with advanced melanoma. Comparing with the control group who received chemotherapy, GC101 TIL therapy demonstrated statistically significant and clinically meaningful efficacy improvement, potentially to benefit patients with advanced melanoma who failed PD-1 antibody.

Schedule your 30 min Free 1stOncology Demo!
Discover why more than 1,500 members use 1stOncology™ to excel in:

Early/Late Stage Pipeline Development - Target Scouting - Clinical Biomarkers - Indication Selection & Expansion - BD&L Contacts - Conference Reports - Combinatorial Drug Settings - Companion Diagnostics - Drug Repositioning - First-in-class Analysis - Competitive Analysis - Deals & Licensing

                  Schedule Your 30 min Free Demo!

Addressing the Unmet Need in the Treatment of Advanced Melanoma

Unlike cutaneous melanoma which is predominant in Western population, melanoma in East Asia is primarily composed of acral melanoma and mucosal melanoma. The differences in subtypes result in distinct patient outcomes. For instance, the objective response rate (ORR) and duration of response (DoR) of PD-1 antibody as the first treatment setting for advanced melanoma in China are only around 1/3 of those in Western population.

Conventional TIL therapies can offer deep and durable clinical benefits, but the requirements of high-intensity lymphodepletion chemotherapy and high-dose IL-2 administrations may lead to severe adverse events and even mortality.

The MIZAR-003 study selected for this ASCO (Free ASCO Whitepaper) LBA is an open-label, randomized, active-controlled, multicenter pivotal Phase II clinical trial. Initiated in December 2024 and led by Professor Jun Guo of Peking University Cancer Hospital. The trial was conducted across 25 leading cancer centers in China. The study aims to evaluate the efficacy and safety of GC101 in patients with advanced melanoma who have failed prior PD-1 antibody therapy, with the primary endpoint being progression-free survival (PFS).

Juncell’s GC101 TIL Therapy Demonstrates Exceptional Efficacy

All enrolled patients in MIZAR-003 had advanced melanoma that failed prior PD-1 antibody therapy. The median number of prior systemic therapy lines was 2, acral and mucosal melanoma accounted for 81.8% of patients, the median sum of the diameters (SOD) of target lesions was 68.4 mm, 89.9% of patients had distant metastasis, with more than half of the patients having metastases involving ≥ 3 organs. Among these, 66.7% had metastases to vital organs including the liver, lungs, and bones. After randomization, baseline characteristics were balanced between the GC101 treatment group and the control group.

As the first registrational randomized controlled trial (RCT) of a TIL therapy in late-line melanoma globally, MIZAR-003 met its primary endpoint, achieving clinical trial success. According to the data presented, the median progression-free survival (PFS) in the GC101 treatment group was 4.3 months, which was significantly superior to 1.6 months in the chemotherapy control group (HR=0.43,95% CI 0.26~0.68,P=0.0002), representing a 57% reduction in the risk of progression or death. Overall survival (OS) data are not yet mature but have shown a clear trend of benefit.

The ORR in the GC101 treatment group was 42.0%, representing a substantial improvement over the 6.1% observed in the control group. Moreover, some patients in the treatment group converted from long-term partial response (PR) to complete response (CR), demonstrating excellent efficacy.

Juncell’s GC101 TIL Therapy Exhibits Favorable Safety Profile

Unlike conventional TIL therapy which requires high-intensity lymphodepletion chemotherapy and high-dose IL-2 administration, GC101 TIL therapy adopts an innovative regimen featuring low-intensity preconditioning and no IL-2 administration, thereby reducing related adverse events.

In terms of safety profile, compared with conventional TIL therapies, adverse events following GC101 treatment were substantially lower in both incidence and grade, with shorter duration. The median duration was 8 days.

(Press release, Juncell Therapeutics, JUN 3, 2026, View Source;juncell-therapeutics-gc101-til-therapy-achieves-primary-endpoint-in-the-pivotal-phase-ii-trial-for-pd-1-antibody-failed-advanced-melanoma-302790931.html [SID1234666414])