Evaluating Zevalin followed by stem cell transplantation for relapsed or refractory NHL

This study evaluated the safety and effectiveness of ibritumomab tiuxetan (Zevalin) followed by high-dose chemotherapy and autologous stem cell transplantation (ASCT) in patients with relapsed (cancer recurrence) or refractory (does not respond to treatment) non-Hodgkin’s lymphoma (NHL). This study concluded that ibritumomab tiuxetan followed by BEAM (carmustine, etoposide, cytarabine, melphalan) chemotherapy and ASCT is a safe and effective treatment for these high-risk patients.

Salvage chemotherapy (treatment of remaining or recurrent cancer) followed by high-dose chemotherapy and ASCT is the current standard of care for patients with relapsed or refractory NHL. However, patients who do not respond to chemotherapy tend to have poorer outcomes.

Radioimmunotherapy with ibritumomab tiuxetan may help these patients achieve better outcomes after ASCT. This type of treatment uses monoclonal antibodies (proteins made in the laboratory that can bind specifically to cancer cells) that release radiation directly on the tumor. The safety and effectiveness of the ibritumomab tiuxetan, BEAM, and ASCT treatment sequence in patients with relapsed or refractory NHL remain under investigation.

This study involved 37 patients with relapsed or refractory NHL. 62.2% of patients had diffuse large B-cell lymphoma or primary mediastinal lymphoma. 24.3% of patients had follicular lymphoma and 8.1% of patients had mantle cell lymphoma. Patients received ibritumomab tiuxetan followed by BEAM chemotherapy and ASCT. Patients were followed-up for an average of 61 months.

Overall, 87% of patients responded to treatment. 59% of patients achieved a complete response (no signs of cancer). 27% of patients achieved a partial response (tumor shrinkage).

At follow-up, 3-year progression-free survival (patients still alive 3 years later without disease progression; PFS) was 61%. 3-year overall survival (patients still alive 3 years later; OS) was also 61%. 

In a separate analysis, the outcomes of these patients were compared to 21 patients who received BEAM without ibritumomab tiuxetan. In patients with relapsed NHL, those who received BEAM and ibritumomab tiuxetan had a significantly higher PFS compared to those who received BEAM only (78% vs. 22%). OS was also significantly higher (83% vs. 22%).

21.6% of patients treated with ibritumomab tiuxetan experienced unexplained fever. 10.8% of patients reported severe infections. These were resolved with antibiotics. 27.0% of patients reported severe to life-threatening mucositis (red, sore mouth or gums or open sores).

This study concluded that ibritumomab tiuxetan followed by BEAM and ASCT is a safe and effective treatment for patients with relapsed or refractory NHL. However, the authors suggest that this treatment may benefit more patients with relapsed disease.

This study was retrospective, meaning it looked back in time to analyze data. Also, the patient populations in this study were quite small. Larger studies are needed to confirm these results.