Investigators line up Keytruda, cancer vax combo trial in glioblastoma

Keytruda is set for testing as part of a combo with Agenus’ cancer vaccine Prophage in glioblastoma.

In what could see another use added to Merck & Co.’s immuno-oncology star Keytruda, the checkpoint inhibitor is set for testing in glioblastoma as part of a combo with Agenus’ cancer vaccine Prophage.

Investigators will test the combo against a Keytruda monotherapy in a total of 45 patients with newly diagnosed glioblastoma (GBM). In previous trials, Prophage, a heat shock protein-based vaccine, has shown improved progression-free survival against the brain cancer.

The phase 2 trial will be done in collaboration with the National Cancer Institute, according to a release. Academic centers of the Brain Tumor Trials Collaborative will conduct the study.

Glioblastoma is notoriously known for being the most aggressive brain tumor with almost a certainty of fast recurrence and a comparatively shorter length of survival than other cancers.

A three-way immuno-oncology battle between Keytruda, Bristol-Myers' Opdivo and Roche's Tecentriq is due to heat up, and the three companies are busy looking at opportunities for a potential boost to sales. Among those opportunities are pairing with cancer vaccines as each looks to get ahead of the competition.

Merck has already combined Keytruda with Genexine’s cancer vaccine GX-188E in clinical tests for HPV-induced cancers, and Bristol-Myers kicked off testing of Opdivo with Bavarian Nordic’s CV301 in non-small cell lung cancer. Roche’s Genentech is exploring the possibility of Tecentriq with BioNTech’s personalized cancer vaccine platform.

But Keytruda’s competition might not just come from Opdivo and Tecentriq. In a potentially landmark study published in the New England Journal of Medicine at the end of last year, a complete response was observed in a patient with recurrent multifocal GBM who was treated with a CAR-T therapy. Remission was sustained for seven-and-a-half months.

At the same time, Bethesda, Maryland-based Northwest Biotherapeutics has been working for years in GBM with its therapeutic cancer vaccine candidate DCVax-L. The company delisted from Nasdaq in December because of rule violations.