Immunomodulation: the role of hematopoietic cytokines

Talimogene Laherparepvec in Combination With Ipilimumab in Previously Untreated, Unresectable Stage IIIB-IV Melanoma

PURPOSE

Combining immunotherapeutic agents with different mechanisms of action may enhance efficacy. We describe the safety and efficacy of talimogene laherparepvec (T-VEC; an oncolytic virus) in combination with ipilimumab (a cytotoxic T-lymphocyte-associated antigen 4 checkpoint inhibitor) in patients with advanced melanoma.

METHODS

In this open-label, multicenter, phase Ib trial of T-VEC in combination with ipilimumab, T-VEC was administered intratumorally in week 1 (10(6) plaque-forming units/mL), then in week 4 and every 2 weeks thereafter (10(8) plaque-forming units/mL). Ipilimumab (3 mg/kg) was administered intravenously every 3 weeks for four infusions, beginning in week 6. The primary end point was incidence of dose-limiting toxicities. Secondary end points were objective response rate by immune-related response criteria and safety.

RESULTS

Median duration of treatment with T-VEC was 13.3 weeks (range, 2.0 to 95.4 weeks). Median follow-up time for survival analysis was 20.0 months (1.0 to 25.4 months). Nineteen patients were included in the safety analysis. No dose-limiting toxicities occurred, and no new safety signals were detected. Grade 3/4 treatment-related adverse events (AEs) were seen in 26.3% of patients; 15.8% had AEs attributed to T-VEC, and 21.1% had AEs attributed to ipilimumab. The objective response rate was 50%, and 44% of patients had a durable response lasting ≥ 6 months. Eighteen-month progression-free survival was 50%; 18-month overall survival was 67%.

CONCLUSION

T-VEC with ipilimumab had a tolerable safety profile, and the combination appeared to have greater efficacy than either T-VEC or ipilimumab monotherapy.

A Dendritic Cell Primer for Oncology Nurses

Once believed to be part of the nervous system, dendritic cells (DCs) now are known to be potent antigen-presenting cells of the immune system. Upon capturing a foreign antigen, the immature DC matures as it travels to the T cells to activate an immune response. DCs can be categorized into two main subsets: DC1s and DC2s. DC1s, also called myeloid-related DCs, arise from early-precursor cells or monocytes and play a role in initiating immune responses against antigens such as cancer cells. Various cytokines stimulate the growth and differentiation of DCs, such as granulocyte macrophage-colony-stimulating factor. DC research is evolving rapidly as a clinical therapy; therefore, nurses should appreciate the cell's mechanisms of action.

Dendritic cells: emerging roles in tumor immunotherapy

The purpose of this article is to examine the use of myeloid dendritic cells (DCs) as immunotherapy in the treatment of cancer. DCs can be stimulated either from circulating blood or bone marrow progenitor cells using cytokines, particularly granulocyte macrophage-colony-stimulating factor (GM-CSF) (e.g., sargramostim, Leukine). GM-CSF has been shown to promote maturation, mobilization, and antigen presentation of DCs in vivo or ex vivo as a therapeutic cancer vaccine. Once stimulated, DCs can present tumor antigen to naive T cells to initiate an immune response. In addition to myeloid-related DC stimulation, antitumor properties of GM-CSF include direct cytotoxicity, antiangiogenesis properties, and potential upregulation of antibody-dependent cellular cytotoxicity. Oncology nurses need to be knowledgeable regarding new therapies. Using knowledge gained through reading professional journals and self-education, nurses can inform patients of new therapies, which may increase patients' hope.