Dr Hanna on Elraglusib Plus Chemotherapy and Immunotherapy in Advanced Salivary Gland Cancer

“When you start to look at a couple of key subgroups, like those patients who had non-adenoid cystic–type salivary [gland] cancer and those who had a little bit of higher expression of GSK 3β staining, there was actually a higher response rate.”

Glenn J. Hanna, MD, director of the Center for Cancer Therapeutic Innovation (Early Drug Development Program) and director of the Center for Salivary and Rare Head and Neck Cancers at Dana-Farber Cancer Institute; as well as an associate professor of medicine at Harvard Medical School, discussed efficacy outcomes from a phase 2 trial (NCT05010629) investigating the GSK 3β inhibitor elraglusib (9-ING-41) plus chemotherapy with or without immunotherapy in patients with advanced salivary gland cancer.

This single-arm, single-center, open-label trial enrolled patients with any primary site of salivary gland cancer. Patients needed to have recurrent or metastatic, incurable disease and could have received any number of prior systemic therapies. They also needed to have measurable disease per RECIST 1.1 criteria with progression in the preceding 12 months, an ECOG performance status of 0 or 1, and adequate bone marrow and organ function.

In part 1, patients received intravenous (IV) elraglusib at 15 mg/kg on days 1 and 4 plus IV carboplatin at an area under the curve of 5 on day 1 of 21-day cycles. In part 2, patients received IV pembrolizumab (Keytruda) at 200 mg on day 1 of cycles 1 and 2, followed by the same elraglusib/carboplatin regimen used in part 1 in cycles 3 and beyond.

In the full population (n = 32), the primary end point of best overall response rate (ORR) per RECIST 1.1 criteria was not met. The ORR in this population was 9.4% (95% CI, 2%-25%). However, among the key subgroup of patients with non-adenoid cystic disease—which was associated with higher nuclear expression of GSK 3β—the ORR was 18%, he said. This outcome is exciting, as an ORR of approximately 20% is typically a signal that a drug or combination regimen might have antitumor activity, he explained.