SunRISe-1: TAR-200, a gemcitabine-releasing device placed in the bladder, for BCG-unresponsive non-muscle-invasive bladder cancer
A small pretzel-shaped device that slowly releases gemcitabine inside the bladder cleared carcinoma in situ in about four out of five patients whose cancer had stopped responding to BCG, offering an alternative to bladder removal.
Open-label phase 2b trial of patients with BCG-unresponsive high-risk non-muscle-invasive bladder cancer with carcinoma in situ, who declined or were unfit for radical cystectomy. Cohort 2 tested TAR-200 monotherapy, an intravesical drug-releasing system placed cystoscopically every three weeks then every twelve weeks for up to two years. Primary endpoint was complete response rate.
The complete response rate was about 84%, with most responses durable beyond a year and a low rate of serious adverse events, mostly urinary symptoms. It led to FDA approval in 2025, the first intravesical drug-releasing system and a rare new option for a group whose only curative alternative is cystectomy.
- Complete response in about 84% of patients with carcinoma in situ (cohort 2, TAR-200 alone).
- Median duration of response over two years, with a majority of responders remaining in complete response at 12 months.
- Most adverse events were low-grade urinary symptoms (frequency, dysuria, urgency); grade 3 or higher treatment-related events in a small minority and rare discontinuations.
- Placement and removal are outpatient cystoscopic procedures requiring no anaesthesia.
- Response rates compared favourably with pembrolizumab (about 41%) and nadofaragene firadenovec (about 51%) in similar populations, though not in a randomised comparison.
Patients with high-risk bladder cancer confined to the lining whose disease has not responded to BCG now have a bladder-sparing option that clears the cancer in most cases, delivered through a simple outpatient procedure. It may allow many to avoid or defer cystectomy, a life-changing operation. Whether responses translate into avoided progression and cystectomy over the long term, and how it compares with cystectomy on survival, remain to be shown.
- Single-arm phase 2b; no randomised comparison with cystectomy or other bladder-sparing options.
- Follow-up is still relatively short for a disease where recurrence and progression occur over years.
- Complete response is a surrogate; progression to muscle-invasive disease is the outcome that matters.
- Requires regular cystoscopy for device exchange and surveillance, and cost is substantial.