The study, which included 649 patients worldwide, was originally designed to measure an improvement in overall survival. However, in prior consultation with the FDA and European regulatory authorities, the primary analysis endpoint was revised to assess improvement in progression-free survival (PFS), defined as the length of time the tumor did not grow or patient death did not occur.
Patients receiving Avastin plus interferon alfa-2a therapy experienced a 59% improvement in PFS compared to those receiving interferon alfa-2a therapy alone. Avastin plus interferon had a median PFS of 10.2 months compared to 5.4 months for patients who only received interferon. The tumor response rate was 31% in the Avastin plus interferon arm, compared to 13% in the patients who received interferon alone.
Hal Barron, Genentech’s senior vice president of development and chief medical officer, said: “This is the fourth kind of cancer in which Avastin has demonstrated positive results in a phase III study, reinforcing our belief in the potential of specifically targeting VEGF in a broad spectrum of solid tumor types.”
Adverse events in this study appeared to be similar to those previously reported for interferon and for Avastin. The most common adverse events that occurred more often in the Avastin plus interferon arm included bleeding, hypertension and proteinuria. Severe fatigue occurred in 23% in the Avastin arm compared to 15% in the interferon alone arm.
Renal cell carcinoma is the most common type of kidney cancer, accounting for nine out of 10 cases, and fewer than 10% of late-stage kidney cancer patients live five years following diagnosis.