Hengrui's HRS-4642 Granted Breakthrough Therapy Designation: Unveiling the High Value of a Global First-in-Class KRAS G12D Inhibitor for Pancreatic Cancer

Hengrui's HRS-4642 Receives Breakthrough Therapy Designation in China for KRAS G12D-Mutant Pancreatic Cancer

In February 2026, China's Center for Drug Evaluation (CDE) added HRS-4642 injection to its Breakthrough Therapy Designation list. The drug, developed by Jiangsu Hengrui Pharmaceuticals Co., Ltd., combines with AG regimen (gemcitabine plus nab-paclitaxel) for first-line treatment of advanced or metastatic pancreatic cancer harboring KRAS G12D mutations.

This designation marks a significant milestone in tackling one of oncology's most formidable challenges: the "king of cancers," pancreatic cancer, which has long resisted targeted therapies.

The Deadly Reality of Pancreatic Cancer

Pancreatic cancer carries the worst prognosis among common malignancies. Global cancer statistics from 2022 show approximately 510,000 new cases and 467,000 deaths worldwide, making it the sixth leading cause of cancer death globally, accounting for roughly 5% of all cancer deaths.

In China, the situation is equally grim: about 119,000 new cases and 106,000 deaths in 2022, ranking 10th in incidence and 6th in mortality among all cancers. The disease's insidious onset means 80% of patients are diagnosed at locally advanced or metastatic stages, missing surgical opportunities. The overall five-year relative survival rate hovers around just 10%.

For years, first-line treatment for advanced pancreatic cancer has relied on chemotherapy. International guidelines recommend FOLFIRINOX (leucovorin, 5-fluorouracil, irinotecan, and oxaliplatin), NALIRIFOX (liposomal irinotecan, oxaliplatin, leucovorin, and 5-fluorouracil), or AG regimen for patients with good performance status, while gemcitabine monotherapy serves those with poorer status. Though these options offer some survival benefit, overall efficacy remains limited, accompanied by varying degrees of hematologic and gastrointestinal toxicity.

KRAS G12D: The "Undruggable" Target

The KRAS oncogene mutates in up to 90% of pancreatic ductal adenocarcinomas (PDAC). Among these, KRAS G12D represents the most common variant at approximately 44%, followed by G12V at 34% and G12R at 20%. For decades, KRAS mutations were considered "undruggable," and no effective targeted therapy existed for the primary driver mutation.

Hengrui developed HRS-4642 as a KRAS G12D inhibitor that specifically binds to the mutant protein, inhibiting MEK and ERK phosphorylation, thereby blocking tumor cell proliferation, invasion, and metastasis. No similar drug has been approved globally.

Promising Phase Ib/II Results

At the 2025 European Society for Medical Oncology (ESMO) Congress in Berlin, Hengrui presented results from a Phase Ib/II study of HRS-4642 combined with chemotherapy in advanced KRAS G12D-mutant pancreatic cancer. The study results have been accepted by Nature Medicine (Impact Factor: 52.5) with Fast Track designation.

The trial enrolled 31 patients, with four in the dose-escalation phase experiencing no dose-limiting toxicities. As of the data cutoff on July 8, 2025, with a median follow-up of 7.5 months, the combination regimen showed impressive efficacy in first-line treatment:

• Objective Response Rate (ORR): 63.3%
• Disease Control Rate (DCR): 93.3%
• Durable Response: Among 19 patients achieving partial response, 18 maintained ongoing response; median duration of response not yet reached
• 6-Month Progression-Free Survival Rate: 89.3%

The data demonstrate that this combination not only achieves deep tumor shrinkage in the short term but also holds promise for translating into long-term survival improvement.

Molecular Clearance and Safety Profile

HRS-4642 combined with AG regimen also showed significant and sustained clearance of KRAS G12D mutant alleles. Among 20 patients with positive baseline circulating tumor DNA (ctDNA), over half (52.6%) achieved complete mutant allele clearance by week 3 of treatment (Cycle 2 Day 1). By week 9 (Cycle 4 Day 1), this proportion climbed to 88.9% (16 patients).

Safety analysis revealed that most Grade 3 or higher treatment-related adverse events were hematologic toxicities. Notably, no treatment-related adverse events led to discontinuation or death.

Breaking New Ground

HRS-4642 represents more than a me-too approach to the RAS space. Rather than following global trends, Hengrui selected KRAS G12D, the most clinically relevant mutation in pancreatic cancer. The development strategy reflects localization based on Chinese patient epidemiology, advancement into first-line combination therapy rather than later-line monotherapy, and progression to randomized Phase III validation.

The CDE's Breakthrough Therapy Designation carries significant weight in China's regulatory system, representing official recognition of clinical value, accelerated development pathways, market potential, and capital validation. This designation marks a critical step forward for Chinese innovative drugs in conquering previously "undruggable" targets.

However, the long-term value of combination strategies requires further rigorous clinical validation, including rational dose exploration, precise timing optimization, and biomarker-based patient stratification. As evidence accumulates, multi-mechanism, multi-dimensional synergistic intervention may build a more effective and durable treatment model for KRAS G12D-mutant patients, ultimately transforming this once "undruggable" target into clinical reality.

References: CDE Breakthrough Therapy Designation Announcement (2020 No. 82); GLOBOCAN 2022 Global Cancer Statistics; 2026 CSCO Pancreatic Cancer Diagnosis and Treatment Guidelines; ESMO 2025 Oral Presentation 2215O; Nature Medicine (Fast Track acceptance).