Is It Safe to Take Sunitinib Long Term?
by Jeni Crockett-Holme
Keywords: Kidney cancer, Sunitinib, Safety, Side effects
When kidney cancer spreads to other organs, it is called metastatic kidney cancer. Treatment may include targeted drug therapy to inhibit cancer growth. Sunitinib (brand name Sutent) is prescribed for this purpose.
Kidney cancer patients who take sunitinib often live 2 years or longer, and survival beyond 6 years has been reported for some patients. With this longer use, more information is needed about the safety of taking sunitinib over the long term.
Studying long-term safety
Early analyses have indicated that long-term use of sunitinib does not increase side effects or cause new ones to develop. To assess long-term safety more formally, a recent study looked at safety data from nine clinical trials of sunitinib in more than 5000 patients with metastatic kidney cancer . The study included more than 800 patients who took sunitinib for 2 years or longer.
In those who took sunitinib long term and in all patients studied, most side effects occurred within the first year of use and then stabilized or decreased over time. Treatment-related side effects included hand-foot syndrome, hypertension, fatigue, and diarrhoea.
The exception was hypothyroidism, which was relatively rare in the first year but increased with use of sunitinib over time. This effect was noted in all patients who took sunitinib and in those who took sunitinib long term.
Implications for treatment
The results of this study suggest that patients can take sunitinib for metastatic kidney cancer long term without compromising safety. Hypertension and other heart-related side effects occurred in the first year and stabilized or decreased over time, as did most side effects. This pattern indicates that continued use of sunitinib does not generally increase the number of side effects or their severity.
Because the occurrence of hypothyroidism was delayed, thyroid levels of patients taking sunitinib should be monitored routinely during treatment. Monitoring and management of hypothyroidism is also important for addressing treatment-related side effects such as fatigue. Hypothyroidism can typically be treated with thyroid hormone replacement therapy, and severe hypothyroidism related to sunitinib use is rare.
Taking sunitinib for metastatic kidney cancer
As long as patients continue to benefit from treatment with sunitinib, the data suggest that it can be prescribed safety over the long term.
 Porta C, Gore ME, Rini BI, et al. Long-term safety of sunitinib in metastatic renal cell carcinoma. Eur Urol 2016;69:345–51.