Today, the U.S. Food and Drug Administration (FDA) granted accelerated approval to pembrolizumab (Keytruda) for the treatment of adult and pediatric patients with refractory primary mediastinal large B-cell lymphoma or those who have relapsed after two or more prior lines of therapy.
Approval was based on data from 53 patients with relapsed or refractory primary mediastinal large B-cell lymphoma enrolled in a multicenter, open-label, single-arm trial, KEYNOTE-170. Patients were treated with pembrolizumab at 200 mg intravenously every 3 weeks until unacceptable toxicity or documented disease progression or for up to 24 months for patients without disease progression.
The overall response rate was 45% (95% confidence interval [CI] = 32%–60%), including 11% complete responses and 34% partial responses. The median duration of response was not reached within the follow-up period (median = 9.7 months). The median time to first objective response was 2.8 months. Pembrolizumab is not recommended for the treatment of patients with primary mediastinal large B-cell lymphoma who require urgent cytoreductive therapy.
The most common adverse reactions in ≥ 10% of patients treated in KEYNOTE-170 were musculoskeletal pain, upper respiratory tract infection, pyrexia, fatigue, cough, dyspnea, diarrhea, abdominal pain, nausea, arrhythmia, and headache. Pembrolizumab was discontinued or interrupted due to adverse reactions in 8% and 15% of patients, respectively. About 25% of patients had an adverse reaction requiring systemic corticosteroid therapy. Serious adverse reactions occurred in 26% of patients.
The recommended pembrolizumab dose for treatment of adults with primary mediastinal large B-cell lymphoma is 200 mg every 3 weeks. The recommended dose in pediatric patients is 2 mg/kg (up to a maximum of 200 mg) every 3 weeks.
Pembrolizumab prescribing information is available at: https://www.keytruda.com/hcp/dosing/.
The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.