New Vaccine Harnesses Immune System Against Multiple Myeloma
In combination with stem cell transplant, vaccination-induced immune response and was associated with long-term control of the disease.
Cancer scientists have developed a vaccine that may improve the response to therapy in patients with high-risk multiple myeloma and may help keep the cancer at bay by stimulating the body’s immune system, according to results published in Clinical Cancer Research, a journal of the American Association for Cancer Research.
The vaccine is based on dendritic cells, which are an essential component of the immune system, helping produce a response that destroys cancer cells, according to Frederick L. Locke, MD, chair of the Blood and Marrow Transplant and Cellular Immunotherapy Department at Moffitt Cancer Center in Tampa, Florida, and senior author of the study.
“Dendritic cell vaccines have the potential to harness the patient’s own immune system to get them into remission and potentially keep the cancer from coming back,” Locke said.
The vaccine targets a protein called survivin, a high level of which at diagnosis is associated with poor outcomes for patients.
“We hypothesized that by targeting this protein, we could induce an immune response in patients who have the most aggressive disease and potentially keep them in remission for a longer period of time,” Locke said.
Multiple myeloma is a chronic and incurable cancer that is often treated with autologous stem cell transplant (ASCT), in which the patient’s own stem cells are removed from the bone marrow or peripheral blood and are stored until they are needed. The patient is treated with chemotherapy to kill as many cancer cells as possible and induce a remission, and then given the transplant.
For this study, the investigators selected patients with high-risk disease who still had active myeloma after induction therapy and before receiving ASCT, which constitutes a negative prognostic factor.
“We focused on this patient population because they are most in need of the vaccine,” said Locke. The vaccine was engineered from dendritic cells collected before treatment.
The researchers tested the vaccine in a phase I clinical trial involving 13 patients.
Study results showed that the vaccine in combination with ASCT was well tolerated, with only minor adverse effects observed.
Overall, 85 percent of patients treated with the experimental vaccine had either T-cell responses or antibody responses to the protein targeted by the vaccine, the results indicated.
Furthermore, seven patients experienced an improved clinical response at 90 days post-transplant, all of whom showed survivin-specific immune responses. After a median follow-up of 4.2 years, six out of these seven patients were alive and remained disease-free after treatment.
The researchers estimated that approximately 71 percent of the patients were alive and did not experience disease progression four years after treatment, as compared to an historical average of about 50 percent, the authors said.
“Our study showed that we can target survivin with a vaccine-based approach and induce immune responses, and it suggested that this strategy could ultimately help improve patient outcomes,” added Locke. “Larger, randomized studies are needed to confirm our findings and to assess whether moving vaccination to earlier in the disease course would be beneficial in preventing patients from developing aggressive forms of myeloma.”