In a significant shift in their oncology programs, Amgen and Ideaya Biosciences have announced the termination of their collaborative effort to develop a combination therapy using the PRMT5 blocker AMG 193 and MAT2A inhibitor IDE397. The decision, revealed in Ideaya's fourth-quarter business report, marks the end of a partnership that began in July 2022.
The original collaboration focused on targeting solid tumors characterized by MTAP-null status, with Amgen leading Phase I studies while both companies shared external costs and clinical development responsibilities. The partnership operated under a mutually non-exclusive clinical trial and supply agreement, with each company maintaining their respective commercial rights.
Despite the setback in the combination approach, both companies are proceeding with independent development paths. Ideaya has announced plans to redirect its efforts toward studying IDE397 in combination with its proprietary PRMT5 inhibitor IDE892, specifically targeting non-small cell lung cancer (NSCLC).
AMG 193 Monotherapy Shows Promise
Amgen's development program for AMG 193 continues to advance, backed by encouraging early clinical data. In recent first-in-human trials, AMG 193 demonstrated notable efficacy as a monotherapy, achieving a 21.4% objective response rate in evaluable patients. The drug showed activity across eight distinct tumor types, including pancreatic adenocarcinoma and both squamous and non-squamous NSCLC.
Safety Profile and Ongoing Development
The safety assessment of AMG 193 revealed adverse events in approximately half of the study participants. The most frequently reported side effects included:
- Nausea (48.8%)
- Fatigue (31.3%)
- Vomiting (30%)
Eight patients experienced dose-limiting toxicities during the study period.
Expanding Clinical Program
Amgen has broadened its clinical investigation of AMG 193, initiating several key studies:
- A Phase II trial focusing on MTAP-null patients with advanced NSCLC
- A Phase I/Ib/II study in MTAP-null solid tumors
- Two Phase Ib studies evaluating the drug both as monotherapy and in combination regimens for:
- MTAP-null thoracic malignancies
- Gastrointestinal, biliary tract, and pancreatic cancers
