Benzinga | Jan 18, 2022 04:03PM EST

Chimerix Announces Publication Of ONC201 Data From Phase 2 Study In Neuroendocrine Tumors In Clinical Cancer Research

Chimerix (NASDAQ:CMRX), a biopharmaceutical company whose mission it is to develop medicines that meaningfully improve and extend the lives of patients facing deadly diseases, today announced that a peer-reviewed article entitled, "Phase 2 Study of ONC201 in Neuroendocrine Tumors including Pheochromocytoma-Paraganglioma (PC-PG) and Desmoplastic Small Round Cell Tumor (DSRCT)," has been published in the journal, Clinical Cancer Research. The article can be accessed here. An interim summary of select cohorts from this study was previously presented at the annual meeting of the American Society of Clinical Oncology (ASCO) in 2021.

ONC201 is an orally administered small molecule dopamine receptor D2 (DRD2) antagonist and caseinolytic protease (ClpP) agonist.

"Given ONC201's demonstrated biological activity with DRD2, we took a deliberate approach to explore its potential utility in neuroendocrine tumors," said Peter Anderson, MD, PhD., Principal investigator and professor, Department Pediatric Hematology/Oncology/BMT at Cleveland Clinic Children's and Case Comprehensive Cancer Center. "Metastatic PC-PG and DSRCT patients had meaningful responses by RECIST criteria, and some were treated for years with improvements in their disease-related symptoms."

"Patients with metastatic neuroendocrine cancers are in need of more effective and well-tolerated treatment options. This efficacy and safety data supports further investigation of ONC201's activity beyond recurrent H3 K27M-mutant diffuse midline glioma," said Allen Melemed, MD, MBA, Chief Medical Officer of Chimerix. "We look forward to continuing to explore additional tumors where ONC201 may provide therapeutic benefit to existing standards of care."

This open-label Phase 2 investigator-initiated study treated 30 patients with rare neuroendocrine tumors. Paraganglioma patients were separated in to two separate cohorts of the study receiving ONC201 either once or twice weekly. A third cohort included patients with other neuroendocrine tumors, including desmoplastic small round cell tumor (DSRCT), dosed weekly with ONC201. The primary endpoint was radiographic response as measured by RECIST criteria.

In the cohort of paraganglioma patients receiving ONC201 once weekly, 50% (5/10) of patients exhibited a partial response (PR) and two additional patients had stable disease (SD) that lasted longer than three months. Five of the 10 patients in this cohort were treated longer than one year. Among the cohort of paraganglioma patients receiving ONC201 twice weekly one PR and seven SD were observed; this cohort includes four of eight patients who crossed over from the weekly dosing cohort. The third cohort of other neuroendocrine tumors included one PR (DSRCT) and two SD (DSRCT; neuroblastoma) that lasted longer than three months. Importantly, across all cohorts there was no decline in Karnofsky Performance Status (KPS) at week 12 for 93% of patients (28/30) and no dose modification due to treatment-related adverse events.