SUMMARY

• INLEXZO (gemcitabine intravesical system) is an intravesical drug releasing system (iDRS), referred to as TAR-200 in literature.¹ 
• Williams et al (2025)² presented a 15-month cost per responder economic model from a Medicare payer perspective to compare the cost per responder of INLEXZO vs United States (US) Food and Drug Administration (FDA)-approved comparator treatments (pembrolizumab, nadofaragene firadenovec [NF], nogapendekin alfa inbakicept [NAI] combination with Bacillus Calmette-Guérin [NAI + BCG], and valrubicin) for US patients with BCG-unresponsive high-risk non-muscle invasive bladder cancer (NMIBC) with carcinoma in situ (CIS) with or without papillary disease. Model inputs included clinical efficacy data (overall complete response [CR] rates, 12-month duration of response [DOR], and radical cystectomy [RC] rates) and costs for initial and subsequent treatment, medical visits, and RC. The model output based on the total cost per patient achieving and sustaining CR for ≥12 months included overall costs and costs related to initial treatment, subsequent treatment, RC, and medical, at 15 months.  
  • At 15 months, the proportion of patients achieving and sustaining CR for ≥12 months was 43.5% for INLEXZO, 18.8% for pembrolizumab, 21.9% for NF, 26.8% for NAI + BCG without reinduction, 36.6% for NAI + BCG with reinduction, and 10.1% for valrubicin.
  • At 15 months (without considering NAI + BCG reinduction), the total cost per patient achieving and sustaining CR for ≥12 months was $1,892,569 for INLEXZO, with the observed cost per responder savings of $698,262 vs pembrolizumab, $406,840 vs NF, $832,346 vs NAI + BCG, and $1,541,999 vs valrubicin.
  • At 15 months (considering NAI + BCG reinduction), the total cost per patient achieving and sustaining CR for ≥12 months was $1,897,937 for INLEXZO, with the observed cost per responder savings of $716,976 vs pembrolizumab, $417,928 vs NF, $162,599 vs NAI + BCG, and $1,568,107 vs valrubicin.

Product labeling

• INLEXZO (gemcitabine intravesical system) [Prescribing Information]. Horsham, PA: Janssen Biotech, Inc; https://www.janssenlabels.com/package-insert/product-monograph/prescribing-information/INLEXZO-pi.pdf.
• INLEXZO (gemcitabine intravesical system) [Instructions for Use]. Horsham, PA: Janssen Biotech, Inc; https://www.janssenlabels.com/package-insert/product-instructions-for-use/INLEXZO-ifu.pdf.

cost per responder analysis

Williams et al (2025)² presented a 15-month cost per responder economic model to compare the cost per responder of INLEXZO vs FDA-approved comparator treatments for US patients with BCG-unresponsive high-risk NMIBC with CIS with or without papillary disease.

Study Design/Methods

• A 15-month cost per responder model was developed from a Medicare payer perspective based on the total cost per patient, defined as achieving and sustaining CR for ≥12 months.
• After treatment initiation, patients could attain CR or not respond.
• Monthly transitions from CR to nonresponse were evaluated based on DOR data. Nonresponders underwent RC or received subsequent novel treatments, with equal distribution assumed among these treatments.
• Scenario analyses included NAI + BCG reinduction as part of both initial and subsequent treatment to evaluate the impact of reinduction on cost per patient, accounting for efficacy and real-world use differences.
• Clinical efficacy inputs (overall CR, 12-month DOR, and RC rates) were extracted from primary clinical trial publications.
  • Swimmer plots were digitized to extract monthly DOR and nonresponse rates for INLEXZO, pembrolizumab, and NAI + BCG; for NF and valrubicin, digitized Kaplan-Meier curves reporting recurrence-free survival were used instead.
  • As prescribing information only provided a 12-month DOR rate, which was insufficient for modeling monthly transitions to nonresponse, monthly DOR data from clinical trial publications (including data for NAI + BCG with and without reinduction) were used for model efficacy inputs.
• Average sales prices were used for initial and subsequent treatment costs, with the exception of INLEXZO (pricing based on forecasts) and valrubicin (generic costs). Costs for medical visits and RC were obtained from published literature.
• The 15-month total cost per patient was calculated using a composite measure of overall CR and 12-month DOR. Costs were reported in 2025 US dollars.
• Results were specific to Medicare-insured patients and may not be generalizable to other populations; real-world data analyses are warranted to confirm findings.

Results

Efficacy Inputs

• Efficacy inputs obtained from clinical trial publications are summarized in Table: Efficacy Inputs for INLEXZO and Other FDA-Approved Treatments for BCG-Unresponsive High-Risk NMIBC With CIS.

Total Cost per Patient at 15 Months

• The total cost per patient achieving and sustaining CR for ≥12 months at 15 months by treatment and comparative observed cost per responder savings are included in Table: Total Cost per Patient Achieving and Sustaining CR for ≥12 Months at 15 Months by Treatment.

• The total cost per patient achieving and sustaining CR for ≥12 months at 15 months with or without NAI + BCG reinduction is included in Table: Total Cost per Patient Achieving and Sustaining CR for ≥12 Months at 15 Months – With or Without NAI + BCG Reinduction.

LITERATURE SEARCH

A literature search of MEDLINE^®, Embase^®, BIOSIS Previews^®, and Derwent Drug File (and/or other resources, including internal/external databases) was conducted on 10 November 2025.