TAR-200 showed high complete response rates in BCG-unresponsive, high-risk non-muscle invasive bladder cancer with CIS in the phase 2b SunRISe-1 study.
Among patients with Bacillus Calmette-Guérin (BCG)-unresponsive, high-risk non–muscle-invasive bladder cancer (NMIBC) with carcinoma in situ (CIS) with or without papillary disease, treatment with TAR-200 — an intravesical chemotherapy releasing system — elicited high complete response rates, according to data from the phase 2b SunRISe-1 study.
These data were shared during the 2025 American Urological Association Annual Meeting, where investigators highlighted data from Cohort 2 of the trial which evaluated 85 patients within this population. Patients who received TAR-200 achieved an overall complete response rate of 82.4% and the 12-month complete response rate was 45.9%.
The Kaplan-Meier–estimated 12- and 24-month complete response rates were 52.4% and 44.7%, respectively. The median time to onset of complete response was 2.8 months and 95.7% of patients achieved a complete response within the first three months. The complete response rate was consistent across patient subgroups.
“The standard of care for [patients with] BCG-unresponsive, high-risk NMIBC is radical cystectomy,” Dr. Joseph Jacob, an associate professor of urology at Upstate University Hospital in Syracuse, New York, said during the presentation. “Radical cystectomy is a life changing operation with considerable morbidity and up to an 8% 90-day mortality rate. Unfortunately, many patients are unable or unwilling to undergo radical cystectomy. There are limited FDA-approved treatment options in patients with BCG-unresponsive, high-risk NMIBC.”
TAR-200 is a novel drug releasing system that employs an intravesical drug releasing application which provides sustained delivery of gemcitabine in the bladder. In December 2023, TAR-200 received breakthrough therapy designation from the FDA for the treatment of adult patients with BCG-unresponsive, high-risk NMIBC who are ineligible for or have declined radical cystectomy. Then in January 2025, a new drug application (NDA) was submitted to the FDA seeking the approval of the agent for the treatment of patients with BCG-unresponsive, high-risk NMIBC with CIS, regardless of the presence of papillary tumors.
Radical cystectomy: removal of the whole bladder; this can include removal of the prostate and seminal vesicles or the uterus, ovaries, fallopian tubes and part of the vagina.
Complete response rate: the disappearance of all target lesions.
Carcinoma in situ (CIS): a group of abnormal cells.
Papillary disease: thin, finger-like cancerous tumors that usually start in the bladder lining and extend into the center of the bladder.
Additional findings from SunRISe-1 displayed that the median duration of response was 25.8 months. High-risk NMIBC recurrence was observed in 32.9% of responders and 5.7% experienced at least T2 disease progression. The 12-month cystectomy-free rate was 86.6%. The estimated 12- and 24-month duration of response probabilities were 56.2% and 51.8%, respectively. The 12-month duration of response rate was 52.9% and 47.1% of responses were ongoing at the data cutoff.
In terms of safety, most treatment-emergent side effects (TRAE) in cohort 2 were grade 1 (mild) or 2 (moderate) and resolved after a median of 3.1 weeks. Five patients experienced at least 1 serious treatment-related side effect and 3.5% of patients discontinued TAR-200 monotherapy due to treatment-related side effect. There were no treatment-related deaths.
Any-grade and grade 3 (severe) or higher treatment-related side effects occurred at rates of 83.5% and 12.9%, respectively. The most common any-grade TRAEs included pollakiuria (43.5%), dysuria (40%), and micturition urgency (24.7%). Grade 3 or higher treatment-related side effects consisted of urinary tract pain (4.7%), bladder pain (2.4%), and urinary tract infection (1.2%).
“Health-related quality of life remained high [during] TAR-200 treatment and TAR-200 monotherapy was well tolerated with rare serious TRAEs and treatment discontinuation,” Jacob said in conclusion. “TAR-200 is under review by the FDA following the submission of a NDA.”
Cohorts 1,2 and 3 of SunRISe-1 enrolled adult patients with histologically confirmed high-risk NMIBC with CIS with or without papillary disease with an ECOG performance status of 2 or less. Patients were also required to have persistent or recurrent disease within 12 months of completion of BCG therapy and be unresponsive to BCG therapy with no plans to undergo a radical cystectomy. Cohort 4 consisted of patients with papillary-only high-risk NMIBC without CIS.
In cohort 1, patients received TAR-200 in combination with cetrelimab and those in cohorts 2 and 3 received TAR-200 or cetrelimab monotherapy, respectively. Patients in cohort 4 also received TAR-200 monotherapy. TAR-200 was administered once every three weeks for the first 24 weeks then every 12 weeks through week 96 of treatment.
In cohorts 1, 2 and 3, the primary end point was overall complete response rate. Key secondary end points consisted of duration of response, overall survival, safety, tolerability and health-related quality of life. In cohort 4, the primary end point was disease-free survival.
At baseline, the median age in cohort 2 was 71 years. Most patients were male, White, former nicotine users, had an ECOG performance status of 0, and had CIS-only disease. The median number of prior doses of BCG was 12 and the median time from last receipt of BCG to CIS diagnosis was 3.2 months.
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