Updated results from SunRISe-1 in NMIBC

Prof Christof Vulsteke, medical oncologist at the Integrated Cancer Center Gent, discussed the outcomes of the SUNRISE-1 trial with Prof Charles van Praet, urologist at the University of Gent and one of the co-authors of the study. 

At ESMO, updated results of this trial, focused on BCG-unresponsive NMIBC, were presented. All patients in the trial had CIS of the bladder that was unresponsive to BCG treatment, with or without papillary disease.

The trial randomised patients into three arms: one receiving a combination of TAR200 and cetrelimab, one with TAR200 monotherapy, and one with cetrelimab monotherapy. TAR200 is a small device that slowly releases gemcitabine into the bladder over time. It is placed via a catheter every three weeks, replaced after a cystoscopy, and later administered every three months.

Early results showed that the TAR200 monotherapy arm had the most promising outcomes, prompting continuation of this arm while the other two were discontinued. The updated ESMO results revealed an impressive complete response rate of 83% at any time for the TAR200 monotherapy group. At one year, the complete response rate was 57%, a significant result for BCG-unresponsive NMIBC patients, whose current standard treatment is radical cystectomy.

With a median follow-up of nine months, 82% of patients who responded to treatment remained in response. However, longer follow-up is needed to assess how well patients can avoid cystectomy over time.

Regarding safety, TAR200 was generally well tolerated. Gemcitabine is a familiar drug for bladder cancer, but the TAR device can cause some local side effects, such as frequent urination, pain during urination and nocturia. Many patients needed anticholinergic medications or mirabegron to manage these symptoms. Importantly, there were no significant systemic side effects, making the safety profile favourable.

In conclusion, TAR200 monotherapy offers a promising bladder-preserving option for patients with BCG-unresponsive NMIBC. While cystectomy remains a viable option, this approach provides an opportunity for those seeking to avoid surgery. Further follow-up will be crucial in determining the long-term durability of these responses.