Immune checkpoint inhibitor Opdivo (nivolumab) appears to be more effective at treating patients with relapsed or refractory classical Hodgkin’s lymphoma than other therapies, a meta-analysis suggests.
The study, “Efficacy of nivolumab as checkpoint inhibitor drug on survival rate of patients with relapsed/refractory classical Hodgkin lymphoma: a meta-analysis of prospective clinical study,” was published in Clinical and Translational Oncology.
Classical Hodgkin’s lymphoma is typically treated with chemotherapy and/or radiation. Although these treatments are effective for some patients, relapsing disease or cancer cells that become resistant to these treatments remain major problems for clinicians.
Immunotherapy involves enhancing the body’s natural ability to destroy tumor cells, and recent advances in this area have shown promise in a number of cancer types. Among the most promising immunotherapies are checkpoint inhibitors, which target the PD-1 pathway or similar pathways.
Normally, the PD-1 pathway is basically a way for healthy cells to signal to immune cells that they are healthy — essentially telling the immune cells that everything is OK. However, cancer cells often hijack this pathway, which allows them to deliver this same “everything is OK” signal to immune cells — even though the immune cells should, ideally, destroy the cancer cells. Thus, the PD-1 pathway lets cancer cells hide from the immune system.
Bristol-Myers Squibb‘s Opdivo is an antibody that targets and blocks the PD-1 pathway. Theoretically, this allows the immune system to identify and destroy cancer cells that would otherwise have remained hidden. However, PD-1-blocking therapies have shown various levels of effectiveness in different cancer types and in different patients.
Opdivo is already approved for classical Hodgkin’s lymphoma patients who failed a prior autologous stem cell transplant and Adcetris (brentuximab vedotin), but a systematic review of Opdivo’s effectiveness in these patients has not yet been conducted.
In this study, the researchers combed databases for previous studies evaluating Hodgkin’s lymphoma patients who had been treated with Opdivo to assess how effective this treatment is for these patients. They identified and analyzed data from seven previous studies, which included that of 560 patients.
Most patients were treated with 3 mg/kg Opdivo every two weeks, although there was some variation among studies.
Of these patients, 68% responded to Opdivo in some capacity, and 16.8% achieved full remission. Specific rates varied from study to study, but the overall response rate in all seven studies was more than 50%.
“The results of the current systematic review and meta-analysis suggest that nivolumab is an effective treatment for patients with relapsed and refractory [classical Hodgkin’s lymphoma],” the researchers wrote.
Common side effects of Opdivo treatment included fatigue, diarrhea, rash, and reactions at the site of injections. However, “the adverse effects of nivolumab are controllable and have a good safety profile,” according to the researchers.
Although this review suggests that Opdivo could be an effective treatment for relapsed or refractory Hodgkin’s lymphoma patients, it is far from a cure-all: A total of 45% of patients experience some form of treatment failure and/or disease progression by three years after treatment. The prognosis is particularly bad for patients who have refractory disease after being treated with an autologous stem cell transplant.
The researchers note that more research still needs to be done; seven studies is far from the body of evidence that will be needed to truly understand which patients will or won’t respond best to a particular treatment. They conclude their review by suggesting that another meta-analysis be performed in a couple of years when, hopefully, more data will be available.