5 minOn June 8, 2026, the clinical-stage biotechnology company Tango Therapeutics announced a major breakthrough in its lead research program. A combination therapy comprising the PRMT5 inhibitor vopimetostat and the RAS(ON) inhibitor daraxonrasib demonstrated a remarkable 92% objective response rate (ORR) in patients with second/third-line pancreatic ductal adenocarcinoma (PDAC). This clinical figure is exceptionally rare in the pancreatic cancer landscape and is being hailed as a potential turning point for the field.
Key Data: A Dual Breakthrough in Efficacy and Durability
The data released are from an ongoing Phase 1/2 study, which enrolled 59 patients with heavily pre-treated MTAP-deleted and RAS-mutant PDAC or non-small cell lung cancer (NSCLC). These patients presented with advanced disease, with over 70% exhibiting liver metastases and more than half receiving the combination as a third-line treatment.
In the highly anticipated "vopimetostat + daraxonrasib" combination arm, patients demonstrated an extraordinary response to treatment:
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92% Objective Response Rate (ORR): Of the 12 evaluable PDAC patients, 11 achieved tumor regression, with 9 responses confirmed.
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100% Disease Control Rate (DCR): All patients in the evaluable group achieved disease control.
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Durable Clinical Benefit: The combination was not only fast-acting but showed significant durability. Data indicated a 90% 6-month progression-free survival (PFS) rate, with the median PFS not yet reached, signaling powerful therapeutic potential.
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Favorable Safety Profile: The combination was well-tolerated across all dosage levels. The majority of adverse events were Grade 1 or 2; no related Grade 4 or 5 adverse events were observed, and there were no discontinuations due to adverse events.
Cracking the "King of Cancers": A Synthetic Lethality Paradigm
Pancreatic ductal adenocarcinoma (PDAC) has long been regarded as one of the most intractable malignancies in oncology. Epidemiological data indicates that pancreatic cancer remains one of the leading causes of cancer-related mortality globally, with a 5-year survival rate that has stagnated around 10% for years. For patients with metastatic disease, standard treatments like FOLFIRINOX or gemcitabine plus albumin-bound paclitaxel offer limited benefit and are often accompanied by significant, debilitating toxicities.
The core challenge in treating pancreatic cancer lies in its complex genetic background and robust drug-resistance mechanisms. Tango Therapeutics is addressing this through a precision medicine approach based on synthetic lethality.
Vopimetostat is a PRMT5 inhibitor designed specifically for MTAP-deleted tumor cells, which selectively blocks cancer cell survival pathways. When combined with RAS(ON) inhibitors—developed by Revolution Medicines, such as daraxonrasib—the therapy effectively launches a "pincer movement" against the oncogenic signaling network.
"Chemotherapy has long been the standard of care for pancreatic cancer, yet it presents significant tolerability challenges and overall limited efficacy," said Dr. Brian Wolpin, Director of the Hale Family Center for Pancreatic Cancer Research at Dana-Farber Cancer Institute. "These early combination data demonstrate the potential to meaningfully reshape how we treat this disease with a precision-guided, chemotherapy-free approach."
Strategic Acceleration: Aiming for Phase 3 and First-Line Development
Given the strength of the clinical data, Tango Therapeutics has rapidly pivoted its strategic focus, planning to advance the vopimetostat and daraxonrasib combination directly into Phase 3 development. The company aims to establish this as a first-line treatment regimen for patients with MTAP-deleted pancreatic cancer.
Upcoming Milestones:
- 2H 2026: Finalize the design of the Phase 3 randomized-controlled trial for the first-line combination approach.
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2H 2026: Present comprehensive data on the vopimetostat + RAS(ON) inhibitor combination in second/third-line PDAC patients at an international scientific conference.
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Pipeline Expansion: Initiate a combination study of vopimetostat plus ERAS-0015 and continue monitoring the monotherapy data in lung cancer.
While the data for the vopimetostat and daraxonrasib combination remain in the early stages, the 92% ORR, 90% 6-month PFS rate, and the favorable safety profile constitute one of the most promising signals in pancreatic cancer research in recent years.
More importantly, this research demonstrates not just the success of a single drug, but the clinical viability of a new therapeutic paradigm: "Synthetic Lethality + RAS Inhibition." For the approximately 40% of pancreatic cancer patients harboring MTAP deletions, a precision therapy guided by molecular profiling and freed from the limitations of traditional chemotherapy is moving from concept to reality.
