Inlexzo & SunRISe-1: Enthusiasm and Caution From Two Leading Clinicians

For urologists and oncologists already familiar with the SunRISe-1 data, there is no question that Inlexzo is a promising new options for patients facing bladder cancer, but there are still questions about how to make the patient experience better, minimize side effects, and potentially put more exciting agents within the pretzel-shaped system that is inserted into the bladder and provides extended release of gemcitabine for about three weeks.

The phase 3 SunRISe-1 study evaluated this sustained-release, intravesical gemcitabine system in patients with BCG-unresponsive high-risk non–muscle invasive bladder cancer (NMIBC) — a population for whom radical cystectomy has long remained the standard of care. The study demonstrated that durable complete responses could be achieved in a meaningful proportion of patients, establishing a credible bladder-sparing alternative in a space historically defined by limited efficacy and high surgical rates.

“From a scientific standpoint, this is a new paradigm in treating bladder conditions,” Dr. Joseph Jacob, a leading bladder cancer expert and one of the authors of the SunRISe-1 Study, told SurivorNet. “Using a device that dwells in the bladder for three weeks to treat a bladder condition is very exciting.  The potential future applications are endless.”

At the same time, real-world implementation considerations remain front and center. “There’s a little bit of the logistics in that these pretzels need to be taken out and put back in the bladder every three weeks,” says Dr. Gary Steinberg, a long-standing leader in NMIBC management, referencing the Inlexzo’s pretzel shape. “That means a cystoscopy in the office. Patients don’t like to be cystoscope all that much. They don’t like to have their lower urinary tract instrumented.”

Dr. Steinberg also pointed to tolerability considerations. “We do know from the package of labeling that there are a fair number of local urinary tract symptoms and adverse events from the pretzel,” Dr. Steinberg adds.

Still, Dr. Jacob believes the broader clinical implications are significant. “From a patient standpoint, this new treatment option will give urologists and patients a great alternative to radical cystectomy,” Dr. Jacob said. “At this point, when considering this new data, I do believe the standard is changing. I believe we will spare more bladders now that we have very good drugs in this space.”

He also underscored quality-of-life implications as central to adoption. “This is the primary driver,” he noted, pointing to the growing acceptance of bladder-sparing strategies as efficacy improves.

Dr. Steinberg acknowledged the pharmacologic rationale behind prolonged intravesical exposure. Historically, chemotherapy is retained for only one to two hours. Sustained release, he said, “in theory…would be a better way to give the chemotherapy,” potentially improving absorption while avoiding systemic toxicity. However, he cautioned that durability remains an open question. “As we follow these patients out longer, the durability decreases,” he noted, reinforcing his view that sequencing — and possibly combining — intravesical chemotherapy and immunotherapy will be critical.

For the HCP community, SunRISe-1 signals progress — but also raises critical questions about durability, sequencing, and combination strategies in an increasingly crowded bladder-sparing landscape