Bernard J. Escudier, MD
Everolimus provides clinical benefit to patients with papillary metastatic renal cell carcinoma (RCC), offering promising overall survival (OS) results and a tolerable side-effect profile, investigators found in a study presented during the 2013 European Cancer Congress (ECC) in Amsterdam.
The findings were the updated results of the phase II, open-label, multicenter RAPTOR study, whose preliminary data were presented at the 2012 ECC. The study evaluated the benefit of first-line everolimus in these patients, who have limited treatment options; there is no standard of care for papillary RCC.
The study was the first to investigate the use of the mTOR inhibitor for the initial treatment of this disease, the ECC noted in a written statement.
“Our results showed that for 59% of patients who received everolimus as their first-line treatment, their disease did not get worse and remained stable. These findings are important and indicate that more than half of these cancer patients are getting some kind of benefit from everolimus treatment,” said Bernard J. Escudier, MD, head of the French Group of Immunotherapy and chairman of the Genitourinary Tumour Board at the Institut Gustave Roussy in Villejuif, France.
“Advanced papillary kidney cancer is a very difficult cancer to treat, and because there is no standard of care, there is disagreement amongst experts regarding the best treatment option for these patients. Our clinical findings are encouraging and suggest that everolimus may represent a new treatment option.”
Eligible participants were adults aged 23 to 84 years who had type I or II disease, an ECOG performance status of ≤1, and no previous systemic therapy for RCC. They received 10 mg of oral everolimus daily until disease progression or unacceptable toxicity. The study’s primary endpoint was the proportion of patients who were progression-free at 6 months. Secondary endpoints included progression-free survival (PFS), OS, and safety.
The most recent analysis was conducted in January, after the study had been in progress for 3.5 years. It included 92 patients in total, evaluated in three separate groupings: all 92 in a group looked at for drug safety; an intent-to-treat (ITT) group of 83 patients; and a group of 63 who participated “per protocol” (PP), or without major protocol violations.
In PP patients, the 6-month PFS rate was 58.7% according to local review and 34.9% based on central review. By local and central review, respectively, median PFS totaled 7.8/3.9 months in the PP population and 7.6/3.7 months in the ITT population.
Median OS was 21 months in ITT patients and 20 months in PP patients.
Grade ≥3 adverse events included asthenia (10.9%), fatigue (5.4%), and anemia (5.4%), with 27.2% of patients discontinuing the drug due to side effects.
Escudier B, Bracarda S, Maroto JP, et al. Open-label phase II trial of first-line everolimus monotherapy in patients with papillary metastatic renal cell carcinoma: RAPTOR final analysis. Presented at: European Cancer Congress 2013; September 27-October 1, 2013; Amsterdam, The Netherlands. Abstract 2706.