Pembrolizumab Trial in TNBC Terminated, 1 of 8 Patients Achieves pCR

Trial results for the Phase 2 study (NCT04095689) investigating pembrolizumab, docetaxel chemotherapy, and interleukin-12 gene therapy in triple negative breast cancer (TNBC) were posted on ClinicalTrials.gov on 2026-01-23. The study, which enrolled 8 participants, was terminated. Of the enrolled participants, 1 achieved a pathological complete response, while all 8 experienced treatment-related adverse events.

Background

Pembrolizumab (Keytruda) is an immune checkpoint inhibitor. This study investigated its use alongside docetaxel chemotherapy and adenoviral-mediated interleukin-12 (ADV/IL-12) gene therapy. The research focused on patients with anthracycline-refractory, triple negative breast cancer (TNBC), a challenging form of breast cancer.

Trial design

The study (NCT04095689) was a Phase 2 trial with an enrollment of 8 participants. It investigated the safety and effectiveness of docetaxel chemotherapy and pembrolizumab plus adenoviral-mediated interleukin-12 (ADV/IL-12) gene therapy. The target population was patients with anthracycline-refractory, triple negative breast cancer (TNBC). The trial's overall status is TERMINATED.

Key results

Key measurements from the trial included the pathological complete response (pCR) rate and the number of participants experiencing treatment-related adverse events. For the outcome of "Pathological Complete Response (pCR) Rate of Docetaxel Chemotherapy and Pembrolizumab Plus IL-12 Gene Therapy," 1 participant in the experimental group achieved pCR. For the outcome of "Number of Participants With Treatment-related Adverse Events," 8 participants in the experimental group experienced such events.

What this means

The termination of this Phase 2 trial and the observed results suggest challenges in the combination therapy of pembrolizumab, docetaxel, and IL-12 gene therapy for anthracycline-refractory triple negative breast cancer. While 1 participant achieved a pathological complete response, all 8 participants experienced treatment-related adverse events, indicating potential safety concerns or an unfavorable risk-benefit profile in this small cohort.

Source

The information regarding these trial results was obtained from ClinicalTrials.gov, a public database of clinical studies. The results for study NCT04095689, titled "Docetaxel Chemotherapy and Pembrolizumab Plus Interleukin-12 Gene Therapy in Triple Negative Breast Cancer," were posted on 2026-01-23 on clinicaltrials.gov.