Sirtex Medical has today announced that is has received US Food and Drug Administration (FDA) approval for its SIR-Spheres Y90 resin microspheres for the treatment of unresectable hepatocellular carcinoma (HCC) in the USA.
With this approval, SIR-Spheres is the only radioembolization therapy approved for the treatment of both metastatic colorectal cancer (mCRC) of the liver and HCC in the USA.
HCC is the most common form of liver cancer in adults in the USA, according to the American Cancer Society. Radioembolization, commonly referred to as selective internal radiation therapy (SIRT), with SIR-Spheres uses personalised dosimetry to deliver the optimal dose of radiation directly to tumours in patients with HCC. This approval gives clinicians expanded flexibility in selecting a liver-directed therapy that aligns with patient-specific needs and treatment goals, states a company press release.
“The expanded indication makes SIR-Spheres the only Y90 treatment approved in the USA for both HCC and mCRC,” said Matt Schmidt, chief executive officer of Sirtex. “This milestone reflects our ongoing commitment to delivering flexible, personalised therapies—with multiple dose options available daily—that empowers physicians to treat patients when and where it works best.”
This regulatory milestone is supported by results from the DOORwaY90 study, a prospective, multicentre, open-label clinical trial evaluating the safety and efficacy of SIR-Spheres in treating HCC. The study enrolled 100 patients across 18 US centres, with 65 patients included in the interim primary efficacy cohort. DOORwaY90 met its prespecified co-primary endpoints, demonstrating a best overall response rate (ORR) of 98.5% as assessed by independent central review. All evaluable patients demonstrated a response, indicating a 100% local tumour control rate. Additionally, the median duration of response (DoR) exceeded 300 days. These findings highlight SIR-Spheres as a highly effective liver-directed therapy with a favourable safety profile.
“This study moves the field of radioembolization forward with reproducible dosimetry outcomes and a strong safety profile linked to very positive clinical results,” said Armeen Mahvash, interventional radiologist at MD Anderson Cancer Center in Houston, USA and co-principal investigator of the DOORwaY90 study. “This will give multidisciplinary care teams the confidence to recommend SIR-Spheres for HCC treatment.”
