Final Results of a Phase I Trial of WST-11 (TOOKAD Soluble) Vascular-Targeted Photodynamic Therapy for Upper Tract Urothelial Carcinoma.
PURPOSE: Vascular-targeted photodynamic therapy (VTP) with the intravascular photosensitizing agent padeliporfin (WST-11/TOOKAD-Soluble) has demonstrated therapeutic efficacy as an ablative treatment for localized cancer with potential adaptation for endoscopic management of upper tract urothelial carcinoma (UTUC). This phase I trial (NCT03617003) evaluated the safety of VTP with WST-11 in UTUC.
MATERIALS AND METHODS: Nineteen patients underwent up to 2 endoscopic VTP treatments, with follow-up for up to 6 months. Patients who had residual or recurrent UTUC (any grade/size) failing prior endoscopic treatment or were unable or unwilling to undergo surgical resection were eligible for inclusion. The primary endpoint was to identify the maximally tolerated dose (MTD) of laser light fluence. A dose escalation model was employed, with increasing light fluence (100-200mW/cm) using a modified continual reassessment method. The secondary endpoint was treatment efficacy, defined by absence of visible tumor and negative urine cytology 30 days post-treatment.
RESULTS: Fourteen (74%) patients received the MTD of 200mW/cm, 2 (11%) of whom experienced a dose-limiting toxicity. The initial 30-day treatment response rate was 94% (50% complete, 44% partial). Eight patients underwent a second treatment, with a final observed 68% complete response rate. Leading toxicities were flank pain (79%) and hematuria (84%), which were transient. No ureteral strictures associated with treatment were identified during follow-up.
CONCLUSIONS: VTP with WST-11 has an acceptable safety profile with strong potential as an effective, kidney-sparing endoscopic management option for UTUC. The recently initiated multi-center phase 3 ENLIGHTED trial (NCT04620239) is expected to provide further evidence on this therapy.
Published In/Presented At
Yip, W., Sjoberg, D. D., Nogueira, L. M., Tracey, A. T., Alvim, R. G., Reisz, P. A., Demac, Q., Benfante, N. E., Vanden Berg, R. W., Kim, K., Al-Ahmadie, H., Lin, O., Bochner, B. H., Dalbagni, G., Donat, S. M., Pietzak, E. J., Hakimi, A. A., Solit, D. B., Scherz, A., Bajorin, D. F., … Coleman, J. A. (2023). Final Results of a Phase I Trial of WST-11 (TOOKAD Soluble) Vascular-Targeted Photodynamic Therapy for Upper Tract Urothelial Carcinoma. The Journal of urology, 101097JU0000000000003202. Advance online publication. https://doi.org/10.1097/JU.0000000000003202
Medicine and Health Sciences
Department of Medicine