Trial results for the Phase 1/2 study (NCT04856189) investigating pembrolizumab in combination with selinexor for cisplatin-ineligible or cisplatin-refractory locally advanced or metastatic urothelial carcinoma were posted on ClinicalTrials.gov on 2026-01-29. The trial was terminated after enrolling only 4 participants.
Background
Pembrolizumab is an immunotherapy drug. The trial investigated its use in combination with selinexor for patients with cisplatin-ineligible or cisplatin-refractory locally advanced or metastatic urothelial carcinoma. Selinexor is a drug that may stop the growth of tumor cells by blocking a protein called XPO1.
Trial design
The study (NCT04856189) was a Phase 1/2 trial, which was terminated. It enrolled 4 participants with advanced urothelial carcinoma, locally advanced urothelial carcinoma, metastatic urothelial carcinoma, or refractory urothelial carcinoma. The trial aimed to find the best dose of selinexor and evaluate its effect with pembrolizumab in this patient population.
Key results
The trial reported several key measurements:
- For the Recommended Phase 2 Dose (RP2D) in Phase 1b, the parameter value was NA mg Selinexor.
- The Objective Response Rate (ORR) in Phase 2 was 75 percentage of patients.
- The number of patients who experienced a Grade 3 or higher adverse event was 1 Participants.
- Progression-free Survival (PFS) was reported as NA months.
What this means
The termination of this Phase 1/2 trial after enrolling only 4 participants indicates that the study did not proceed as initially planned. While an Objective Response Rate (ORR) of 75% was observed in the Phase 2 component, this finding is based on a very small patient cohort and must be interpreted with caution, especially given the trial's termination and the 'NA' reported for the Recommended Phase 2 Dose (RP2D) and Progression-free Survival (PFS). The trial's early cessation suggests that the combination of pembrolizumab and selinexor may not have met the criteria for continued development in this specific patient population or that further dose escalation was not feasible.
Source
The information for this article was obtained from ClinicalTrials.gov, a public database of clinical studies. The trial results for study NCT04856189, titled 'Selinexor and Pembrolizumab for the Treatment of Cisplatin-Ineligible or Cisplatin-Refractory Locally Advanced or Metastatic Urothelial Carcinoma,' were posted on 2026-01-29 on clinicaltrials.gov.