Long-term follow-up of allogeneic stem cell transplantation in relapsed/refractory Hodgkin lymphoma

The Emerging Role of CAR T Cell Therapy in Relapsed/Refractory Hodgkin Lymphoma

Treatment for Hodgkin lymphoma (HL) has evolved considerably from the time it was originally described in the 19th century with many patients now being cured with frontline therapy. Despite these advances, upwards of 10% of patients experience progressive disease after initial therapy with an even higher percentage relapsing. Until recently there had been limited therapeutic options for relapsed and/or refractory HL outside of highly intensive chemotherapy with stem cell rescue. Improved understanding of the pathophysiology of HL, coupled with the emergence of more targeted therapeutics, has reshaped how we view the treatment of relapsed/refractory HL and its prognosis. With this, there has been an increased focus on immunotherapies that can reprogram the immune system to better overcome the immunosuppressive milieu found in HL for improved cancer cell killing. In particular, chimeric antigen receptor (CAR) T cells are emerging as a valuable therapeutic tool in this area. Building on the success of antibody-drug conjugates directed against CD30, CAR T cells engineered to recognize the same antigen are now reaching patients. Though still in its infancy, CAR T therapy for relapsed/refractory HL has shown exceptional promise in early-stage clinical trials with the potential for durable responses even in patients who had progressed through multiple lines of prior therapy. Here we will review currently available data on the use of CAR T cells in HL, strategies to optimize their effectiveness, and how this therapy may fit into the treatment paradigm of HL going forward.

Relapsing/refractory HL after autotransplantation: which treatment?

For advanced-stage Hodgkin lymphoma (HL), front-line chemotherapy, alone or in combination with radiotherapy, leads to 5-year progression-free survival (PFS) rates and freedom-from-treatment failure (FFTF) rates of 70-85%, regardless of the chemotherapy regimen applied. Patients with HL experiencing disease progression during or within 3 months of front-line therapy (primary refractory) and patients whose disease relapses after a complete response have a second chance of treatment. The standard of care for relapsed or refractory HL is second-line chemotherapy followed by autologous stem cell transplantation (ASCT), which can induce long-term remission in approximately 40-50% of patients. However, HL recurrence occurs in about 50% of patients after ASCT, usually within the first year, and represents a significant therapeutic challenge. Allogeneic transplantation from HLA-matched donors represents the standard of care for patients with HL relapsing after- or refractory to ASCT.

Fertility preservation in Hodgkin's lymphoma patients that undergo targeted molecular therapies: an important step forward from the chemotherapy era

In total, 80%-90% of Hodgkin's lymphoma (HL) patients are curable with combination chemoradiotherapy. Due to improvements in therapeutic strategies, 50% of all relapsed/refractory patients may undergo complete clinical responses and have long-term survival. Treatment options for HL are effective, but may have a negative impact on post-chemotherapy fertility. Thus, cryopreservation of semen prior to treatment is recommended for male patients. For female patients, assisted reproductive techniques (ART) consult and fertility preservation should be offered as a therapeutical option. In the last years, new targeted molecules have been available for HL treatment. These new drugs showed a high rate of overall responses in the setting of heavily pretreated patients, most of them in relapse after autologous stem cell transplantation, a group previously considered very poor risk. Up to 50% of patients have a complete response and an improved overall survival. Future studies will address the usefulness of novel molecules as a frontline therapy. Considering the high response and survival rates with monoclonal antibody-based therapeutics, fertility has become a concerning issue for long-term HL survivors. As progress has been made regarding ART, with the rigorous steps planned for HL patients, more survivors will become parents.

How to Approach a Hodgkin Lymphoma Patient With Relapse After Autologous SCT: Allogeneic SCT

Hodgkin lymphoma (HL) is a highly curable B-cell lymphoma, and ∼90% of patients who present with early-stage (stage I-II) disease and 70% of patients who present with late-stage disease will be cured with standard frontline treatment. For patients with relapsed or refractory (r/r) disease after initial therapy, the standard of care is salvage chemotherapy, followed by autologous transplantation (autoSCT). Although this approach will cure a significant proportion of patients, upto 50% of patients will experience disease progression after autoSCT, and this population has historically had a very poor prognosis. In the past, further salvage chemotherapy, followed by allogeneic transplantation (alloSCT), has been the only option associated with a significant probability of long-term survival, owing to a graft-versus-lymphoma effect. However, this approach has been complicated by high rates of treatment-related morbidity and mortality and a high risk of disease relapse. Furthermore, many patients have been unable to proceed to alloSCT because of disease refractoriness, poor performance status, or the lack of a donor. However, significant therapeutic advances in recent years have greatly expanded the options for patients with post-autoSCT r/r HL. These include the anti-CD30 antibody-drug conjugate brentuximab vedotin and the checkpoint inhibitors nivolumab and pembrolizumab, as well as increasing experience with alternative donor alloSCT, especially from haploidentical donors. In the present review, we discuss the current role of alloSCT in the treatment of HL after autoSCT relapse.