Amgen Advances Xaluritamig Into Early-Stage Trial for Hard-to-Treat Ewing Sarcoma

Amgen Inc (AMGN) announced an update on their ongoing clinical study.

Amgen’s latest clinical update centers on a first‑in‑human Phase 1b study titled “A Phase 1b Study to Evaluate the Safety, Tolerability, Pharmacokinetics, and Efficacy of Xaluritamig in Adult, Adolescent and Pediatric Participants With Relapsed or Refractory Ewing Sarcoma.” The trial focuses on patients whose Ewing sarcoma has returned or not responded to prior treatment. Its main goals are to find a suitable dose of Xaluritamig for further testing, understand its safety profile, and get an early read on how well it may work, a key step before any larger, late‑stage programs that could shift the treatment landscape.

The study tests Xaluritamig (also known as AMG 509), an experimental cancer drug given by short intravenous infusion. It is designed to target Ewing sarcoma tumors that have few effective options today. The aim is not just to see if the drug can shrink or slow tumors, but also to identify a dose and schedule that can be used safely across adults, teens, and children with advanced disease.

This is an interventional Phase 1 study run by Amgen, using a non‑randomized, sequential design. In Part 1 (dose confirmation), patients receive different dose levels or dosing schedules of Xaluritamig to find one or more doses that appear safe. In Part 2 (dose expansion), more patients are treated at those doses to better understand early anti‑tumor activity and side effects. There is no placebo or comparison arm, and no masking; all participants and investigators know they are receiving Xaluritamig. The main purpose is exploratory and science‑driven, to build a foundation for future development rather than to prove final clinical benefit.

The study is listed as “Not Yet Recruiting,” with initial submission to the registry dated December 9, 2025. This signals that site activation and patient enrollment are still ahead, and that no outcome data are available yet. The latest update to the record was posted on February 5, 2026, showing that Amgen is actively maintaining the listing as the program moves toward startup. Primary completion and overall completion dates are not yet specified, which is typical at this early stage and means investors should view this as a long‑dated asset with results likely several years out.

For investors, this update reinforces Amgen’s push into innovative oncology, particularly in rare and hard‑to‑treat cancers like Ewing sarcoma. While Phase 1 studies rarely move a large‑cap stock on their own, they support the broader narrative around pipeline depth and scientific reach, which can underpin valuation multiples over time. Success here could strengthen Amgen’s position in targeted oncology and immuno‑oncology, areas where peers such as Roche, Novartis, and smaller biotech players are also active. However, the trial remains high risk and early stage, so near‑term stock impact is likely limited; the main takeaway is incremental confidence that Amgen continues to invest in differentiated assets that could, if successful, open future niche oncology revenue streams. The study is currently ongoing at the setup phase with details and future updates available on the ClinicalTrials portal.

To learn more about AMGN’s potential, visit the Amgen Inc drug pipeline page.