Idiotype Vaccines in the Treatment of B-Cell Non-Hodgkin's Lymphoma

Cancer immunotherapy

Cancer immunotherapy consists of approaches that modify the host immune system, and/or the utilization of components of the immune system, as cancer treatment. During the past 25 years, 17 immunologic products have received regulatory approval based on anticancer activity as single agents and/or in combination with chemotherapy. These include the nonspecific immune stimulants BCG and levamisole; the cytokines interferon-α and interleukin-2; the monoclonal antibodies rituximab, ofatumumab, alemtuzumab, trastuzumab, bevacizumab, cetuximab, and panitumumab; the radiolabeled antibodies Y-90 ibritumomab tiuxetan and I-131 tositumomab; the immunotoxins denileukin diftitox and gemtuzumab ozogamicin; nonmyeloablative allogeneic transplants with donor lymphocyte infusions; and the anti-prostate cancer cell-based therapy sipuleucel-T. All but two of these products are still regularly used to treat various B- and T-cell malignancies, and numerous solid tumors, including breast, lung, colorectal, prostate, melanoma, kidney, glioblastoma, bladder, and head and neck. Positive randomized trials have recently been reported for idiotype vaccines in lymphoma and a peptide vaccine in melanoma. The anti-CTLA-4 monoclonal antibody ipilumumab, which blocks regulatory T-cells, is expected to receive regulatory approval in the near future, based on a randomized trial in melanoma. As the fourth modality of cancer treatment, biotherapy/immunotherapy is an increasingly important component of the anticancer armamentarium.

Patient-Specific Vaccine Therapy for Non-Hodgkin Lymphoma

Follicular non-Hodgkin lymphoma (NHL) is an indolent, or slow-growing, malignant disease of the lymphoid tissue, which usually responds to initial therapy. However, the disease is characterized by multiple relapses and remissions, eventually causing death. Several effective therapies are available, but improvement of overall survival in patients with follicular NHL has not been demonstrated. Stimulation of the immune system to recognize malignant lymphoma cells as foreign has been demonstrated as a viable treatment option for patients with follicular NHL. Patient-specific vaccine therapy is a new form of active immunotherapy being studied for NHL. Clinical trials have shown a benefit for patients receiving this type of therapy. This article will provide a foundation for nurses caring for patients receiving patient-specific vaccine therapy.

Current controversies in follicular lymphoma

Follicular lymphoma (FL) is characterized by its responsiveness to initial therapy, a pattern of repeated relapses, and a tendency for histologic progression to a process resembling diffuse, large B-cell lymphoma. Treatment decisions are complicated by the many effective options now available including combinations of conventional chemotherapy and monoclonal antibody, radioimmunotherapy, new targeted agents, and autologous and allogeneic stem cell transplantation. For selected patients, "watch and wait" or involved field irradiation may still be the most appropriate strategy. When therapy is required, a combination of rituximab and conventional chemotherapy results in improved outcomes compared to chemotherapy alone. Radioimmunotherapy alone or in combination with chemotherapy is an attractive strategy for patients with relapsed disease and may prove to be appropriate first line therapy. The role of stem cell transplant in FL requires further investigation. Novel agents with varied mechanisms of action continue to be developed. Enrollment of patients into clinical trials designed to address the many unanswered questions in FL is essential to improving clinical outcomes.

Phase II trial of idiotype vaccination in previously treated patients with indolent non-Hodgkin's lymphoma resulting in durable clinical responses

PURPOSE

To evaluate idiotype (Id) vaccination as a single agent in previously treated patients with indolent non-Hodgkin's lymphoma.

PATIENTS AND METHODS

Patients underwent biopsy for determination of their lymphoma-specific Id sequence. Recombinant Id protein was manufactured and covalently linked with keyhole limpet hemocyanin (KLH) to generate Id/KLH. Patients received Id/KLH 1 mg on day 1 subcutaneously, with granulocyte-macrophage colony-stimulating factor 250 mug on days 1 to 4, monthly for 6 months. Booster injections were administered until progression. Both clinical and immune responses were evaluated.

RESULTS

Thirty-two previously treated patients received at least one injection of Id/KLH, and 31 were assessed for efficacy. Responses were observed in four patients (one complete response and three partial responses). Median time to onset of response was 5.9 months (range, 2.3 to 14.1 months). Median duration of response has not been reached but should be at least 19.4 months (range, 10.4 to 27.2+ months). Median time to progression is 13.5 months. The most common adverse events were mild to moderate injection site reactions. Six (67%) of nine patients tested demonstrated a cellular immune response, and four (20%) of 20 patients demonstrated an antibody response against their Id.

CONCLUSION

This trial demonstrates that Id/KLH alone can induce tumor regression and durable objective responses. Further study of Id/KLH is recommended in other settings where efficacy may be further enhanced as in first-line therapy or after cytoreductive therapy.