The U.S. Food and Drug Administration (FDA) has approved SIR-Spheres Y-90 resin microspheres, manufactured by Sirtex, for the treatment of unresectable hepatocellular carcinoma (HCC). With this approval, these microspheres become the only radioembolization therapy approved for the treatment of both colorectal cancer that has metastasized to the liver and HCC in the United States.
Radioembolization—commonly referred to as selective internal radiation therapy (SIRT)—with the microspheres uses personalized dosimetry to deliver the optimal dose of radiation directly to tumors 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.
DOORwaY-90 Trial
The approval was supported by results from the DOORwaY-90 study, a prospective, multicenter, open-label clinical trial evaluating the safety and efficacy of SIR-Spheres in treating HCC. The study enrolled 100 patients across 18 U.S. centers, with 65 patients included in the interim primary efficacy cohort. DOORwaY-90 met its prespecified co-primary endpoints, demonstrating a best overall response rate of 98.5% as assessed by independent central review. All evaluable patients demonstrated a response, indicating a 100% local tumor control rate. Additionally, the median duration of response exceeded 300 days. These findings highlight Y-90 resin microspheres as a highly effective liver-directed therapy with a favorable 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, MD, an interventional radiologist at The University of Texas MD Anderson Cancer Center and co-principal investigator of the DOORwaY-90 study. “This will give multidisciplinary care teams the confidence to recommend [these microspheres] for HCC treatment."
About SIR-Spheres
SIR-Spheres Y-90 resin microspheres are indicated for the local tumor control of unresectable hepatocellular carcinoma (HCC) in patients with no macrovascular invasion, Child-Pugh A cirrhosis, well-compensated liver function, and good performance status. They are also indicated for the treatment of unresectable metastatic liver tumors from primary colorectal cancer with adjuvant intrahepatic artery chemotherapy of floxuridine.
