Abstract P111

C-MOPP chemotherapy is a highly efficacious regimen for patients with relapsed classical Hodgkin lymphoma following PD-1 inhibitor treatment failure.

Introduction: Despite excellent outcomes of initial chemotherapy for patients treated with classical Hodgkin lymphoma (cHL), unfortunately up to one third of patients will relapse, and of these, 50% will not respond to high dose chemotherapy / autologous stem cell transplantation. Checkpoint inhibitors (CPI) have shown high response rates in patients with relapsed cHL by restoring the programmed death pathway, though the complete response rates are low and most patients treated with single agent CPI will relapse. The optimal treatment approach for patients who lose response to CPI is not clearly defined, though some investigators have identified that prior CPI therapy may re-sensitise patients to standard chemotherapy.

Aim: To assess the safety and efficacy of C-MOPP (prednisolone 60mg/m2 daily D1-14, procarbazine 100mg/m2 daily D1-14, vincristine 1.4mg/m2 2 D1, 8 and cyclophosphamide 650mg/m2 D1 and 8 of a 28 day cycle) chemotherapy in patients with cHL who have lost response to CPI therapy.

Methods: Retrospective analysis of patients with relapsed cHL treated at Monash Health with C-MOPP chemotherapy after CPI therapy.

Results: A total of 4 patients received a median of 3 cycles (range 2-6) of C-MOPP chemotherapy. The median age was 29 years (range 23-48 years). All 4 patients had been treated with ABVD, then a range of subsequent therapies including brentuximab vedotin and autologous stem cell transplant (2 patients) prior to CPI therapy.

All 4 patients treated with C-MOPP achieved a complete metabolic response, allowing 3 patients to proceed to allogeneic bone marrow transplant.

At a median follow-up of 1.8 years (range 0.2 to 2.7), one patient (who did not receive allogeneic bone marrow transplant) relapsed, however all other patients remained in complete response.

C-MOPP was generally well tolerated with nausea and haematological toxicity being the main adverse effects identified.

Conclusion: C-MOPP chemotherapy is a well-tolerated and highly efficacious chemotherapy regimen in patients with cHL who are refractory to CPI therapy and should be considered in this challenging patient cohort.