Slow release device eliminates bladder cancer in 82% of patients

The TAR-200 slow-drug-release device is proving more effective in eliminating bladder cancer than standard therapy. – Image credit Keck Medicine USC

CANCER DIGEST – Nov. 23, 2025 – A new slow-release chemotherapy system may be a more effective treatment for common bladder cancer than current therapy, according to results of a new clinical trial.

The new device, TAR-200, was effective in producing long-term remission in 82 percent of patients treated with the device alone in the phase 2 clinical trial conducted at 144 cancer centers worldwide. The results were published in the July 30, 2025 Journal of Clinical Oncology

“Traditionally, these patients have had very limited treatment options. This new therapy is the most effective one reported to date for the most common form of bladder cancer,” said Sia Daneshmand, MD, in a press release. He is director of urologic oncology at Keck Medicine of University of Southern California and lead author of a study. “The findings of the clinical trial are a breakthrough in how certain types of bladder cancer might be treated, leading to improved outcomes and saved lives.” 

The new device called TAR-200 is a miniature, pretzel-shaped device that contains the chemotherapy drug gemcitabine. Conventional therapy consists of gemcitabine injected into the bladder where it only stays for a few hours. The new device slowly releases the chemotherapy into the bladder over a period of three weeks per treatment cycle.

The TAR-200 device is inserted into the bladder through a catheter in a brief office procedure. The device stays in the bladder for about three weeks, slowly releasing the gemcitabine over that time. The device is then removed using a cystoscope. The procedure is repeated every three weeks for the first six months and then every 12 weeks for up to two years.

In the clinical trial, 218 patients with high-risk non-muscular-invasive bladder cancer whose tumors had not responded to conventional therapy were divided in to four groups. Group 1 (53 patients) were treated with TAR-200 implant along with an immunotherapy drug called cetrelimab, Group 2 (85 patients) received treatment with the TAR-200 implant alone, Group 3 (28) received the immunotherapy alone. A fourth group of patients (52) had higher risk papillary disease, were treated with TAR-200 alone.

This type of bladder cancer is considered high-risk when the location and type of tumor indicate a high probability of recurrence, or of spreading to the bladder muscles or other nearby tissues. The standard treatment for these patients is an immunotherapy drug, called Bacillus Calmette-Guerin (BCG). All these patients had previously received BCG treatment but their cancer had returned.

The results showed that for Group 1, the complete response rate was 67.9 percent, meaning the cancer was undetectable in 36 of 53 patients. In Group 2, 70 of 83 patients (82.4 percent) achieved a complete response, and in Group 3, 13 of 28 patients (46.4 percent) achieved a complete response. Patients in Group 4 did not achieve a complete response but 70 percent survived 12 months before cancer returned. 

For the TAR-200 alone patients (Group 2) the complete response was sustained for a median of 25.8 months. The results showed the treatment with TAR-200 along with cetrelimab was not as effective and had more side effects.

The trial is one of several ongoing trials testing the effect of TAR-200 and the slow release of cancer-fighting drugs for the treatment of bladder cancer. Based on results so far, the FDA has granted the TAR-200 a New Drug Application Priority Review, meaning it will receive an expedited review for approval.

Investigators disclosed that Daneshmand has received grants/research funding and travel reimbursement from Johnson & Johnson and consulting payments from Johnson & Johnson Innovative Medicine (formerly Janssen Pharmaceuticals).

Sources: Keck Medicine of USC press release and the Journal of Clinical Oncology