Trial results for the Phase 1 study (NCT03436056) investigating pembrolizumab in combination with stereotactic body radiotherapy (SBRT) for metastatic non-small-cell lung cancer were posted on ClinicalTrials.gov on 2026-01-29. The study reported 0 participants with dose-limiting toxicities in the dose escalation cohort, though the trial was terminated with an enrollment of only 2 participants.
Background
The study, titled "PembRolIzuMab and Stereotactic Body Radiotherapy In Metastatic Non-small-cell lunG Cancer Patients," aimed to evaluate the combination of pembrolizumab and SBRT in patients with advanced NSCLC. These patients had progressed beyond at least one line of palliative chemotherapy, and an EGFR or ALK inhibitor if applicable, requiring further palliative systemic treatment.
Trial design
The Phase 1, single-center, non-randomized, open-label study (NCT03436056) was designed to investigate pembrolizumab and stereotactic body radiotherapy in patients with metastatic non-small-cell lung cancer. The trial was terminated with an enrollment of 2 participants.
Key results
The trial results for the Dose Escalation Cohort - DOSE LEVEL 1, which included 2 participants, reported the following outcomes:
- Proportion of Patients With Dose Limiting Toxicity: 0 Participants
- Acute Toxicity Rate: 0 Participants
- Acute Toxicity Rate: 1 Participant
- Acute Toxicity Rate: 1 Participant
- Late Toxicity Rate: 1 Participant
- Late Toxicity Rate: 0 Participants
- Late Toxicity Rate: 1 Participant
- Overall Response Rate: 0 Participants
- Disease Control Rate: 2 Participants
- Overall Survival at Six Months: 2 Participants
- Overall Survival at 12 Months: 1 Participant
- Progression Free Survival at 6 Months: 1 Participant
What this means
The results from this terminated Phase 1 study, with an enrollment of only 2 participants, provide very limited data. However, for the small cohort evaluated, no dose-limiting toxicities were observed. While 0 participants showed an overall response, a disease control rate of 2 participants and overall survival at six months for 2 participants were noted. The termination of the trial and the small sample size preclude drawing definitive conclusions about the efficacy or broader safety profile of pembrolizumab combined with SBRT in this patient population.
Source
The information for these trial results was obtained from ClinicalTrials.gov, a public database of clinical studies. The results for study NCT03436056, titled "PembRolIzuMab and Stereotactic Body Radiotherapy In Metastatic Non-small-cell lunG Cancer Patients," were posted on 2026-01-29 on clinicaltrials.gov.