TAR-200, an investigational intravesical gemcitabine releasing system, offers a potential new treatment option. Data from the SunRISe-1 study, including recently updated results from Cohort 2, support its potential clinical utility in this patient population.
Durable Clinical Response Without Reinduction
In Cohort 2 of SunRISe-1, TAR-200 achieved an observed complete response (CR) rate of 82.4%. The median time to onset of response was 2.8 months (range, 2.1–8.3), with 95.7% (67 of 70) of CRs achieved at the first disease assessment, indicating a rapid and early therapeutic effect. Importantly, response was assessed using a rigorous protocol that included quarterly cystoscopy, quarterly central cytology, mandated bladder biopsies with central pathology review at Weeks 24 and 48, and local imaging every 24 weeks. This comprehensive methodology adds confidence to the durability and accuracy of the reported outcomes.
Most recently, data presented at the 2025 AUA annual meeting show that at the 12-month mark, 52.9% (37 of 70) of responders maintained a complete response following a single round of treatment with TAR-200 with the estimated Kaplan-Meier CR rate at 12 and 24 months was 52.4% (40.7-62.8) and 44.7% (33.1-55.7), respectively, and 86.6% of responders remaining cystectomy at 12-months.1 This is particularly impressive, as other treatment protocols allow for reinduction. The SunRISe-1 protocol did not permit reinduction, and patients who did not respond to the initial course were withdrawn from the trial -- strengthening the significance of the observed durability. This sets it apart from regimens requiring repeated dosing to achieve similar endpoints.
The Importance of a Bladder-Sparing Option
Approximately 96% of the patients in the study were eligible for radical cystectomy but declined the procedure. This highlights a persistent challenge in urologic oncology: the disconnect between guideline-driven treatment and patient preference. For many patients, bladder preservation remains a priority, even when faced with high-risk disease.
Illustrating this, in our clinic, an 84-year-old patient with a solitary kidney declined cystectomy. Though eligible for radical cystectomy, he was clear in his refusal: preserving his bladder -- and his independence -- was non-negotiable. He remained physically active and engaged in daily life, including golfing regularly. Treated with TAR-200, he remained active and recurrence-free two years later -- an outcome that aligned both with clinical goals and patient preference.
TAR-200 offers a potential alternative for patients who are unwilling or unable to undergo radical surgery. It provides an outpatient treatment option that can be delivered without the need for anesthesia or hospitalization.
Integration into Practice: Procedural Simplicity
TAR-200 is administered in the clinic using a placement catheter and lidocaine jelly. In our experience, the procedure requires approximately 1-2 minutes. According to trial data, the placement success rate across study sites was 99%, indicating broad procedural feasibility.
Another feature of TAR-200 is its shelf-stable formulation. Unlike other intravesical therapies that require compounding, refrigeration, or coordination with specialty pharmacies, TAR-200 can be stored at room temperature and made available at the point of care. This represents a potential operational benefit, particularly for community urologists or practices with limited pharmacy infrastructure.
Finally, the device insertion procedure is intuitive. After initial training, nurse practitioners in our clinic routinely performed insertions independently, underscoring the accessibility of the procedure.
Safety Profile and Management of Adverse Events
The safety profile of TAR-200 is consistent with other intravesical therapies, primarily involving bladder-related symptoms such as frequency, urgency, and dysuria. These events are generally mild to moderate and manageable with standard pharmacologic agents like anticholinergics.
It is worth noting that adverse events may present more gradually compared to weekly intravesical therapies. This is because TAR-200 remains in the bladder for extended periods, resulting in a more sustained, low-grade irritation rather than acute flares. In clinical practice, proactively prescribing symptomatic medications at the start of therapy has proven beneficial in minimizing patient discomfort and improving adherence.
Additionally, the three-week interval between placements reduces the burden of frequent clinic visits, which is an important consideration for patients traveling long distances or managing other comorbidities.
Novel Mechanism and Future Potential
TAR-200 represents the first intravesical device designed to deliver chemotherapy in a sustained-release format over several days. This approach addresses a longstanding challenge in bladder cancer care: insufficient drug exposure time. Conventional intravesical therapies are limited by how long a patient can retain the medication, with large doses prompting urgency. TAR-200 circumvents this limitation by releasing gemcitabine slowly and continuously, which likely enhances therapeutic exposure and the depth of tissue penetration.
Looking ahead, this is a promising delivery system that is adaptable and could be used as a new mode of treatment delivery with other therapeutic agents in the future.
Conclusion
TAR-200 delivers the highest response rate -- along with remarkable durability -- in a system simple enough for everyday urology practice.
A New Drug Application (NDA) for TAR-200 was submitted to the FDA in early 2025 and is currently under review. If approved, TAR-200 may offer a clinically meaningful alternative for patients with BCG-unresponsive HR-NMIBC, especially those with carcinoma in situ.
Written by: Joseph Jacob, MD, MCR, Urologic Oncologist and Associate Professor of Urology at Upstate Cancer Center, Syracuse, NY
References:
- Jacob, J. M. (2025, April). TAR-200 monotherapy in patients with Bacillus Calmette-Guérin–unresponsive high-risk non–muscle-invasive bladder cancer carcinoma in situ: 1-year durability and patient-reported outcomes from SunRISe-1. Abstract presented at the American Urological Association Annual Meeting, Las Vegas, Nevada.