NEW YORK – Ideaya Biosciences on Monday said it will begin a Phase I/II clinical trial of its investigational MAT2A inhibitor IDE397 plus Amgen's PRMT5 inhibitor AMG193 in solid cancers harboring MTAP deletions.
The US Food and Drug Administration cleared Ideaya and Amgen's investigational new drug application allowing for the start of a trial, in which the drugmakers will evaluate the combination regimen's safety, tolerability, pharmacokinetics, pharmacodynamics, and preliminary efficacy.
Though Amgen is sponsoring the trial under a previously announced collaboration, the drugmakers will evenly split third-party costs associated with conducting the trial and will be responsible for any internal trial-associated costs. The companies have agreed to share clinical data and intellectual property and to keep the commercial rights to their own agents. Ideaya and Amgen have established a joint oversight committee to address regulatory activities related to the treatment combination.
Ideaya is separately evaluating IDE397 as a monotherapy in MTAP-deleted tumors including squamous cell non-small cell lung, esophageal, and bladder cancer. However, Ideaya and Amgen believe their two agents have synergistic activity. In preclinical studies, the firms demonstrated that inhibiting MAT2A and PRMT5 together can deepen the biological response in MTAP-deleted tumors.
"We have a deep understanding of the underlying biological rationale for this combination of a MAT2A inhibitor and an MTA-cooperative PRMT5 inhibitor," Ideaya CSO Michael White said in a statement. "Combined pharmacological inhibition of MAT2A and PRMT5 deepens the biological response through maximal pathway suppression [and] the enhanced combination effect was observed selectively in MTAP-null models."