TAR-200 monotherapy achieves over 80% complete response in high-risk non-muscle-invasive bladder cancer

Updated findings from the SunRISe-1 Phase 2b study have illuminated the promising potential of TAR-200 in treating patients with high-risk non-muscle-invasive bladder cancer (HR-NMIBC) resistant to Bacillus Calmette-Guérin (BCG). Johnson & Johnson shared these significant results at the 2024 American Urological Association Annual Meeting, highlighting the swift and enduring efficacy of TAR-200.

In a cohort of 85 patients, predominantly elderly (median age 71), the study demonstrated an 82.8% complete response (CR) rate, confirmed centrally through urine cytology or biopsy. Impressively, 98% of these responses were achieved within the first 12 weeks, underscoring the rapid action of TAR-200. The study followed respondents for a median period of 29.9 weeks, noting that 85% of responders maintained their CR status at the time of data cutoff. Crucially, none of the patients saw their condition progress to muscle-invasive bladder cancer or metastasis.

"The high complete response rate and durability of these responses observed in patients treated with TAR-200 underscores the potential of this treatment approach for patients with BCG-unresponsive HR-NMIBC," explained Joseph Jacob, M.D., from Upstate Medical University. He emphasized that these findings could be pivotal for patients seeking bladder-sparing treatments, a significant need given the limited options available.

Adverse events related to the treatment were reported in 71.8% of patients. Common side effects included increased frequency of urination (35.3%), painful urination (29.4%), urgency (15.3%), and urinary tract infections (15.3%). More severe adverse events occurred in a smaller percentage, with 8.2% experiencing Grade 3 or higher events, and 4.7% having to discontinue the treatment due to side effects. No deaths were linked to the therapy.

Christopher Cutie, M.D., Vice President at Johnson & Johnson Innovative Medicine, emphasized the significance of these findings in their ongoing mission to enhance bladder cancer treatment. He pointed out that TAR-200 represents a potential shift in therapy, focusing on bladder preservation and addressing unmet patient needs.

TAR-200 operates as a targeted release system designed to administer gemcitabine directly to the bladder over an extended period. This investigational device is placed in a doctor's office via a brief, non-anesthetic procedure. The FDA has recognized TAR-200's potential, awarding it Breakthrough Therapy Designation for treating patients unresponsive to BCG and not opting for radical cystectomy.

Bladder cancer remains a prevalent concern in the U.S., being the sixth most common cancer with over 83,000 new cases annually. Non-muscle-invasive bladder cancer accounts for the majority of these diagnoses. While BCG immunotherapy has been the standard treatment for decades, a significant proportion of patients (30-40%) do not respond to it, often leading to disease recurrence or progression. In such cases, radical cystectomy is the primary treatment, though it involves major surgery and significant lifestyle changes.

The SunRISe-1 study is an open-label Phase 2 clinical trial assessing TAR-200's safety and efficacy, both alone and in combination with cetrelimab, a monoclonal antibody. Patients who are ineligible for or decline radical cystectomy are randomly assigned to different treatment cohorts, focusing on complete response rates and other secondary outcomes like overall survival and quality of life.

In conclusion, the SunRISe-1 Phase 2b study's results present a hopeful future for TAR-200 as a treatment for HR-NMIBC, addressing a critical gap in bladder cancer therapy by offering a potentially effective and bladder-sparing alternative for patients.