Proliposomal Paclitaxel in Non–Muscle Invasive Bladder Cancer: Study Supports Move to Phase IIb
Posted: Wednesday, February 10, 2021
Neal Shore, MD, FACS, of the Carolina Urologic Research Center, Myrtle Beach, and colleagues conducted an early-phase study to evaluate the efficacy and safety of TSD-001 in patients with non–muscle invasive bladder cancer. TSD-001 is a proliposomal paclitaxel formulation intended for intracavitary delivery that remains in the urine for up to 48 hours. At the 2020 Annual Meeting of the Society of Urologic Oncology (SUO, Abstract 24), these researchers reported this therapy to be tolerable and generally safe in this population, supporting its move into phase IIb clinical development.
The researchers evaluated 15 patients with Ta, low-grade non–muscle invasive bladder cancer. In phase I, six patients underwent transurethral resection of the bladder tumor followed by a biweekly dose escalation of 10 to 540 mg of TSD-001 by intravesical administration. In phase IIa, the nine remaining patients were treated weekly for 6 to 8 weeks to assess the marker lesion response rate. Patients who had highly recurrent intermediate-risk disease and were heavily pretreated received 360 mg of TSD-001 once weekly for 6 to 8 weeks. Urine and blood samples were obtained 15 minutes before and 2 hours after each dose instillation.
The marker lesion response rate was 56%, and the 1-year recurrence-free survival rate for patients in phase I was 83%. Up to 48 hours after intravesical instillation, the presence of paclitaxel in the voided urine samples was demonstrated to be above the inhibitory concentration-50 levels of T24 bladder cancer cells.
Grade 3 or 4 treatment-related adverse events were not observed in these groups and were otherwise mild or moderate but not dose-limiting. Urinary health-related quality of life was not found to have changed before or after study completion.
Disclosure: For full disclosures of the study authors, visit suo.abstracts.secure-platform.com.