The PLANeT trial demonstrated that the addition of low-dose pembrolizumab (50 mg every 6 weeks) to standard chemotherapy significantly increased pathological complete response rates in patients with triple-negative breast cancer compared to chemotherapy alone. The study suggests that low-dose pembrolizumab is a feasible option in settings with limited access to standard dosages, showing comparable efficacy to higher doses used in prior studies.
Study
|
Phase II, randomized, open-label study [PLANeT trial] |
| Localized triple-negative breast cancer, stage II-III |
| Pembrolizumab 50 mg + ddAC + paclitaxel (n=78) vs ddAC + paclitaxel (n=79)
|
Efficacy
|
Pathological CR: 53.8% vs 40.5% (p=0.047) |
| Residual cancer burder 0-1: 71.6% vs 61.0%
|
Safety
|
Grade >=3 AEs: Anemia (14.1% vs 29.1%), Neutropenia (43.6% vs 49.4%) |
| Immune-related AEs: Thyroid dysfunction (3.8% vs 0%) |
| Treatment discontinuation due to AEs: Not reported
|
Ann Oncol. Published online XXX
http://doi.org/10.1016/j.annonc.2025.12.015
Reviewed by Ulas D. Bayraktar, MD on Jan 21, 2026
