GRWD5769 Shrinks Tumors 30% in 15 Patients Across 6 Cancers in Phase 1 Trial

2 articles · Updated · The Guardian · Jun 1

83 patients whose cancers had stopped responding to treatment received GRWD5769 plus cemiplimab, and 26 saw tumors shrink; 15 had reductions of at least 30%.
GRWD5769 works by inhibiting ERAP1, stripping tumor cells of an “invisibility cloak” that had prevented T-cells—and immunotherapy—from detecting and attacking them.
The phase 1 trial found activity in cervical, bladder, liver, bowel, lung, and head and neck cancers, with disease held for at least six months in 18% to 55% of patients depending on tumor type.
Researchers said the tablet drug was generally well tolerated and notable for showing efficacy this early in development, especially in patients with few or no remaining options.
The results were presented at ASCO in Chicago, and a larger study is planned as investigators test whether the early benefits can translate into durable clinical gains.

Sources

The Guardian12d ago

Experimental Drug GRWD5769 Shrinks Tumors by 30% in Early Cancer Trial, Exposing Hidden Cancer Cells

The Guardian11d ago

Pat Brogan's Lung Cancer Tumors Shrink by Third with Smart Drug GRWD5769

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This 'smart drug' disables cancer's invisibility cloak. How many other hard-to-treat cancers could it now conquer?

Promising Phase 1 Data for GRWD5769: Oral Antigen Modulation Therapy Targets Hard-to-Treat Cancers

Overview

The early-stage clinical trial of GRWD5769, reported on June 1, 2026, showed encouraging results for patients with advanced cancers that had stopped responding to previous treatments. The study observed unusual positive outcomes across several hard-to-treat cancer types, highlighting the drug’s potential broad applicability. These initial findings mark a significant step forward in understanding GRWD5769’s impact, as its ability to elicit responses in refractory cases is a key indicator of its promise. Overall, the results suggest that GRWD5769 could become an important option for patients with resistant cancers.

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