Updated data from a trial of Johnson & Johnson’s experimental “pretzel” showed that more than 80% of bladder cancer patients who got the treatment saw their tumors melt away, building on a readout last year.
The results, released at the American Urological Association meeting on Friday, are the latest data from J&J’s SunRISe-1 trial. Out of 58 patients who have received the treatment and had a three-month follow-up, 48 (83%) have had a complete response. Last year at ESMO, J&J reported that 23 out of 30 (77%) patients achieved a complete response.
The silicone “pretzel,” formally known as TAR-200, delivers a decades-old chemotherapy called gemcitabine in low doses over time. The patients enrolled in the study had non-muscle invasive bladder cancer — meaning that their cancer hasn’t infiltrated deeper into the bladder muscle — that did not respond to a vaccine called Bacillus Calmette-Guérin, which is typically used to treat the disease. The patients also were not eligible for or declined bladder surgery.
The updated results also showed that the responses appear to be sticking: At one year, an estimated 74.6% continued to respond to treatment. And out of 48 responders, 41 remained in complete response as of a Jan. 2 data cutoff.
“The high complete response rate and durability of these responses observed in patients treated with TAR-200 underscores the potential of this treatment approach,” Joseph Jacob, a urologist with SUNY Upstate Medical University and the trial’s primary investigator, said in J&J’s press release. “These results address an area of high unmet need for bladder sparing therapies in this patient population.”
Jacob presented the results at the AUA meeting on Friday. Also on Friday, CG Oncology reported results from its oncolytic virus therapy for non-muscle invasive bladder cancer, showing that it helped clear tumors in 75% of bladder cancer patients in a Phase 3 study.
Johnson & Johnson said the study finished enrolling in late 2023. Eighty-five patients who received the therapy have been evaluated for safety.
The most common treatment-related adverse events with J&J’s device were frequent, painful or urgent urination, as well as urinary tract infections. Investigators reported that seven patients had grade 3 or higher treatment-related adverse events and four had one or more serious adverse events. Four patients discontinued treatment.
Johnson & Johnson acquired the “pretzel” technology in its buyout of Taris Biomedical in 2019.