First-line sunitinib therapy for metastatic renal cell carcinoma (mRCC) has somewhat differing effectiveness and safety when used in real-world practice, compared with clinical trials, suggests the OSSMAR multicenter retrospective cohort study.
Investigators led by Marwan Ghosn, MD, Hotel-Dieu de France University Hospital and Saint Joseph University, Beirut, Lebanon, analyzed outcomes among 289 patients with mRCC started on sunitinib (Sutent), an oral multitargeted tyrosine kinase inhibitor, between 2006 and 2016 at 10 centers in Africa and the Middle East region.
The patients had a median age at diagnosis of 58.7 years, and 85.8% had clear cell histology. Two-thirds had metastases at diagnosis, and 15.2% and 31.4% had favorable- and poor-risk disease, respectively, according to expanded Memorial Sloan Kettering Cancer Center criteria. Overall, 52.2% had undergone partial or radical nephrectomy, and nearly all were receiving sunitinib as first-line therapy.
Study results, reported in the Journal of Global Oncology, showed that the mean total sunitinib starting dose was 48.1 mg, with most patients (87.6%) started on a dose of 50 mg. On average, the drug was given for 9.6 months.
The overall response rate was 20.8%, and responses lasted for a median of of 8.2 months. With a median follow-up of 7.8 months, patients had a median time to progression of 5.7 months and a median overall survival of 7.8 months. The 12- and 24-month rates of overall survival were 34.3% and 11.4%, respectively.
Although 60.9% of patients experienced adverse events, only 8.0% experienced serious adverse events. The main adverse events were gastrointestinal and hematologic, mirroring those seen previously in trials. About a third of the whole study cohort (28.7%) discontinued sunitinib therapy.
“OSSMAR is the first study in the Middle East involving several Arab countries and evaluating the use of real-time sunitinib in the treatment of mRCC. As a result, this study is of primary importance because it allows for a better assessment of the actual effectiveness and practical adverse events of sunitinib in the population in our region,” Dr. Ghosn and coinvestigators maintained.
Compared with patients in clinical trials, OSSMAR patients had poorer overall survival, possibly due to factors such as a relatively lower nephrectomy rate, real-world influences such as comorbidities, and losses to follow-up, the investigators proposed.
At the same time, the OSSMAR cohort also had a lower rate of adverse events, although this difference likely reflects less rigorous assessment of toxicity in real-world practice, they noted.
Dr. Ghosn disclosed that he has relationships with numerous pharmaceutical companies. The study did not receive any specific funding.
SOURCE: Ghosn M et al. J Glob Oncol. 2019 Oct 5. .