AUA 2023: Efficacy and Safety of Mitomycin Gel (UGN-101) as an Adjuvant Therapy After Complete Endoscopic Management of Upper Tract Urothelial Carcinoma

(UroToday.com) The 2023 American Urological Association (AUA) annual meeting held in Chicago, was host to an upper tract transitional cell carcinoma podium session. Dr. Craig Labbate presented the results of a study analyzing the efficacy and safety of mitomycin gel (UGN-101) as adjuvant therapy following complete endoscopic management of upper tract urothelial carcinoma (UTUC).


Endoscopic-only management of UTUC lesions is associated with high rates of early failure (~50%). Previous attempts at adjuvant treatment of UTUC lesions have included the use of aqueous mitomycin C in the 1990s. However, the routine use of aqueous mitomycin C was complicated by the need for slow infusions and the need to position patients in the Trendelenburg position.

Mitomycin C in the form of JELMYTO (UGN-101) utilizes an RTGel® reverse-thermal hydrogel technology allowing for a dwell time of 4-6 hours. The OLYMPUS trial was a phase 3, open-label, single arm, multicenter prospective study that evaluated a six weekly induction course of JELMYTO in patients with new or recurrent non-invasive LG UTUC. A complete response was observed in 58% of patients, with a further 11% having a partial response. Significantly, 82% of patients with a complete response maintained such a response for 12 months.

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The objective of this study was to evaluate the oncologic efficacy and safety profile of UGN-101 instillations after complete endoscopic ablation of UTUC lesions. This was a retrospective, multicenter analysis from 13 US-based sites, commenced post-commercialization.

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This cohort included 52 patients who received adjuvant therapy and had at least 1 post-treatment surveillance ureteroscopy to evaluate for disease recurrence. The median follow-up was 6.9 months.

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With regards to baseline characteristics, 85% had low grade disease (15% with high grade disease received UGN-101 off-label) and 83% received the full 6-week induction course. Disease was present in the renal pelvis in 73% of patients, with over half having multifocal disease (56%). Ureteral-only disease was present in 6^ of patients.

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At the primary endoscopic evaluation (i.e., the first surveillance ureteroscopy performed), 69% of patients had no evidence of recurrent tumor. This proportion was significantly higher for low-grade patients (72% versus 50% for high grade).

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Next, the authors evaluated whether ipsilateral disease-free survival varied based on whether UGN-101 was administered for adjuvant or chemoablative purposes (an additional, separate cohort of 73 patients). As demonstrated below, ipsilateral recurrence-free survival was significantly better in the adjuvant group, highlighting the importance of mechanical tumor ablation, where feasible.

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As expected, disease-free survival was worse for patients with multifocal disease.

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Next, the authors evaluated disease progression, defined as development of high-grade disease, increase in cT stage, or development of metastatic disease. As demonstrated below, none of the patients in the adjuvant UGN-101 group had any progression events, with significantly higher rates of progression in the chemoablative  cohort.

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Ureteral stenosis was observed in 19% and 28% of patients in the adjuvant and chemoablative groups, respectively, which were both significantly lower than the rates observed in the OLYMPUS trial (44%). Of note, 40-50% of patients in this cohort had UGN-101 instilled via a nephrostomy tube (all via retrograde instrumentation in OLYMPUS).

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Dr, Labbate concluded that:

  • Among patients receiving adjuvant UGN-101 following endoscopic management of UTUC lesions, the recurrence-free rate at the first examination 3 months post-operatively was 69%.
  • High grade lesions are more likely to recur at 3 months (50% versus 28%)
  • Progression events are rare following complete endoscopic ablation of UTUC lesions with adjuvant UGN-101
  • Low rate (18%) of ureteral stenosis in the adjuvant UGN-101 group
  • Longer follow-up is planned with prospective registries

Presented by: Craig Labbate, MD, Society of Urologic Oncology Fellow, MD Anderson Cancer Center, Houston, TX

Written by: Rashid K. Sayyid, MD, MSc – Society of Urologic Oncology (SUO) Clinical Fellow at The University of Toronto, @rksayyid on Twitter during the 2023 American Urological Association (AUA) Annual Meeting, Chicago, IL, April 27 – May 1, 2023