Trial results for pembrolizumab (Keytruda) in relapsed or refractory classical Hodgkin's lymphoma (rrcHL) and primary mediastinal large B-cell lymphoma (rrPMBCL) were posted on ClinicalTrials.gov on 2025-02-10. The study reported an objective response rate (ORR) of 70.0% for rrcHL and 66.7% for rrPMBCL, as assessed by Blinded Independent Central Review (BICR).
Background
Classical Hodgkin's Lymphoma (cHL) and Primary Mediastinal Large B-cell Lymphoma (PMBCL) are types of lymphoma, a cancer that originates in lymphocytes. Patients with relapsed or refractory forms of these diseases often have limited treatment options.
Trial design
This Phase 2 study (NCT04875195) was completed with an enrollment of 66 participants. It investigated pembrolizumab in patients with Relapsed or Refractory Classical Hodgkin's Lymphoma (rrcHL) or Relapsed or Refractory Primary Mediastinal Large B-cell Lymphoma (rrPMBCL). The primary objective was to evaluate the objective response rate (ORR) in each cohort, as assessed by the investigator according to Lugano classification criteria 2014.
Key results
The study evaluated objective response rates (ORR) and pharmacokinetic parameters:
- For Relapsed or Refractory Classical Hodgkin's Lymphoma (rrcHL), the ORR as assessed by the investigator was 66.7%. When assessed by Blinded Independent Central Review (BICR), the ORR was 70.0%.
- For Relapsed or Refractory Primary Mediastinal Large B-cell Lymphoma (rrPMBCL), the ORR as assessed by the investigator was 50.0%. When assessed by Blinded Independent Central Review (BICR), the ORR was 66.7%.
Pharmacokinetic measurements for pembrolizumab across both cohorts included:
- Maximum Serum Concentration (Cmax) Early Cycle: 127.5 µg/ml
- Maximum Serum Concentration (Cmax) Steady State: 154.8 µg/ml
- Trough Serum Concentration (Ctrough) Early Cycle: 17.9 µg/ml
- Trough Serum Concentration (Ctrough) Steady State: 33.8 µg/ml
Regarding Antidrug Antibody (ADA) levels for pembrolizumab, 62 participants were evaluated, and 1 participant showed ADA levels.
What this means
The objective response rates observed in this Phase 2 study suggest that pembrolizumab may offer a beneficial treatment option for patients with relapsed or refractory classical Hodgkin's lymphoma and primary mediastinal large B-cell lymphoma. The consistent ORR findings between investigator assessment and BICR, particularly the 70.0% ORR in rrcHL and 66.7% in rrPMBCL by BICR, indicate a clinically meaningful activity in these challenging populations. The pharmacokinetic data provides further understanding of pembrolizumab's drug exposure in these patients.
Source
The information regarding these trial results was obtained from ClinicalTrials.gov, a public database of clinical studies. The results for study NCT04875195, titled "A Study of Pembrolizumab (MK-3475) in Relapsed or Refractory Classical Hodgkin's Lymphoma (rrcHL) or Relapsed or Refractory Primary Mediastinal Large B-cell Lymphoma (rrPMBCL) (MK-3475-B68)," were posted on 2025-02-10 on clinicaltrials.gov.