Use of Pembrolizumab for Active Brain Metastases in Patients With Melanoma
Posted: Monday, December 17, 2018
Pembrolizumab appears to be active in patients who have melanoma and untreated brain metastases. According to the findings of a phase II clinical trial published in the Journal of Clinical Oncology, this immunotherapy displayed “acceptable toxicity and durable responses.” In addition, 2-year survival in patients with and without brain metastasis who were treated with anti–PD-1 agents was similar.
“Concordant brain and extracerebral responses support [the] use of pembrolizumab to treat small, asymptomatic brain metastases,” stated Harriet M. Kluger, MD, of the Yale Cancer Center, New Haven, Connecticut, and colleagues.
Over the course of 24 months, pembrolizumab was administered at 10 mg/kg every 2 weeks to 23 enrolled patients—all of whom were diagnosed with melanoma and had at least 1 asymptomatic, untreated 5- to 20-mm brain metastasis. Brain metastasis response was observed in 6 patients (26%), although 8 patients (35%) were unevaluable for brain metastasis response due to disease progression or the need for radiation therapy.
Furthermore, the median progression-free survival was 2 months, the overall survival was 17 months, and 11 patients (48%) were alive at 24 months. “All patients in our study who achieved an objective response remained in response at 24 months, which is longer than the [central nervous system] response in patients treated with BRAF/MEK inhibitors,” noted the authors.
Toxicity analyses revealed that 65% of patients treated with pembrolizumab experienced neurologic adverse events. All of these events except for 1 were grade 1 or 2.