Upendra P. Hegde

Pembrolizumab for patients with melanoma or non-small-cell lung cancer and untreated brain metastases: early analysis of a non-randomised, open-label, phase 2 trial.

BACKGROUND Immunotherapy targeting the PD-1 axis has activity in several tumour types. We aimed to establish the activity and safety of the PD-1 inhibitor pembrolizumab in patients with untreated brain metastases from melanoma or non-small-cell lung cancer (NSCLC). METHODS In this non-randomised, open-label, phase 2 trial, we enrolled patients aged 18 years or older with melanoma or NSCLC with untreated brain metastases from the Yale Cancer Center. Patients had at least one untreated or progressive brain metastasis between 5 and 20 mm in diameter without associated neurological symptoms or the need for corticosteroids. Patients with NSCLC had tumour tissue positive for PD-L1 expression; this was not required for patients with melanoma. Patients were given 10 mg/kg pembrolizumab every 2 weeks until progression. The primary endpoint was brain metastasis response assessed in all treated patients. The trial is ongoing and here we present an early analysis. The study is registered with ClinicalTrials.gov, number NCT02085070. FINDINGS Between March 31, 2014, and May 31, 2015, we screened 52 patients with untreated or progressive brain metastases (18 with melanoma, 34 with NSCLC), and enrolled 36 (18 with melanoma, 18 with NSCLC). A brain metastasis response was achieved in four (22%; 95% CI 7-48) of 18 patients with melanoma and six (33%; 14-59) of 18 patients with NSCLC. Responses were durable, with all but one patient with NSCLC who responded showing an ongoing response at the time of data analysis on June 30, 2015. Treatment-related serious and grade 3-4 adverse events were grade 3 elevated aminotransferases (n=1 [6%]) in the melanoma cohort, and grade 3 colitis (n=1 [6%]), grade 3 pneumonitis (n=1 [6%]), grade 3 fatigue (n=1 [6%]), grade 4 hyperkalemia (n=1 [6%]), and grade 2 acute kidney injury (n=1 [6%]) in the NSCLC cohort. Clinically significant neurological adverse events included transient grade 3 cognitive dysfunction and grade 1-2 seizures (n=3 [17%]) in the melanoma cohort. INTERPRETATION Pembrolizumab shows activity in brain metastases in patients with melanoma or NSCLC with an acceptable safety profile, which suggests that there might be a role for systemic immunotherapy in patients with untreated or progressive brain metastases. FUNDING Merck and the Yale Cancer Center.

Phase II Study of Dose-Adjusted EPOCH and Rituximab in Untreated Diffuse Large B-Cell Lymphoma With Analysis of Germinal Center and Post-Germinal Center Biomarkers

PURPOSE To assess the clinical outcome and the influence of biomarkers associated with apoptosis inhibition (Bcl-2), tumor proliferation (MIB-1), and cellular differentiation on the outcome with dose-adjusted (DA) EPOCH (etoposide, prednisone, vincristine, cyclophosphamide, and doxorubicin) plus rituximab (R) infusional therapy in diffuse large B-cell lymphoma (DLBCL) with analysis of germinal center B-cell (GCB) and post-GCB subtypes by immunohistochemistry. PATIENTS AND METHODS Phase II study of 72 patients with untreated de novo DLBCL who were at least 18 years of age and stage II or higher. Radiation consolidation was not permitted. RESULTS Patients had a median age of 50 years (range, 19 to 85) and 40% had a high-intermediate or high International Prognostic Index (IPI). At 5 years, progression-free survival (PFS) and overall survival (OS) were 79% and 80%, respectively, with a median potential follow-up of 54 months. PFS was 91%, 90%, 67%, and 47%, and OS was 100%, 90%, 74%, and 37%, for 0 to 1, 2, 3, and 4 to 5 IPI factors, respectively, at 5 years. The Bcl-2 and MIB-1 biomarkers were not associated with PFS or OS. Based on DA-EPOCH historical controls, rituximab only benefited Bcl-2 positive tumors. Bcl-6 expression was associated with higher PFS whereas GCB exhibited a marginally significant higher PFS compared with post-GCB DLBCL. CONCLUSION DA-EPOCH-R outcome was not affected by tumor proliferation and rituximab appeared to overcome the adverse effect of Bcl-2. Bcl-6 may identify a biologic program associated with a superior outcome. Overall, DA-EPOCH-R shows promising outcome in low and intermediate IPI groups. A molecular model of treatment outcome with rituximab and chemotherapy is presented.

Combination of Imatinib Mesylate with Autologous Leukocyte-Derived Heat Shock Protein and Chronic Myelogenous Leukemia

Purpose: To test the feasibility, safety, immunogenicity, and clinical efficacy of an autologous vaccine of leukocyte-derived heat shock protein 70-peptide complexes (Hsp70PC), in conjunction with imatinib mesylate, in patients with chronic myeloid leukemia (CML) in chronic phase. Experimental Design: Patients had cytogenetic or molecular evidence of disease, despite treatment with imatinib mesylate for all except one patient, at the beginning of study. Hsp70PCs were purified from the leukopheresed peripheral blood mononuclear cells and were administered in eight weekly intradermal injections at 50 μg/dose without adjuvant. Clinical responses were assessed by bone marrow analysis before and after vaccinations. An IFN-γ enzyme-linked immunospot assay was used to estimate the effect of treatment on natural killer cells and T cells against CML. Results: Twenty patients were treated. The manufacturing of Hsp70PCs was successful and the administration was safe for all patients. Minimal or no side effects were reported. Clinical responses were seen in 13 of 20 patients as measured by cytogenetic analysis of bone marrow Philadelphia chromosome–positive cells in metaphases and/or, when possible, the level of Bcr/Abl transcript by PCR. Immunologic responses were observed in 9 of 16 patients analyzed, characterized by an increase in the frequency of CML-specific IFN-γ-producing cells and IFN-γ-secreting natural killer cells in the blood. A significant correlation between clinical responses and immunologic responses was observed. Conclusions: Autologous Hsp70PC vaccination is feasible and safe. When combined with imatinib mesylate, it is associated with immunologic and possible clinical responses against CML in chronic phase.

Effect of CD4+CD25+ and CD4+CD25− T Regulatory Cells on the Generation of Cytolytic T Cell Response to a Self but Human Tumor-Associated Epitope In Vitro

CD4+ T cells naturally expressing CD25 molecules (natural T regulatory cells (Tregs)) have a role in maintaining self tolerance and in regulating responses to infectious agents, transplantation Ags, and tumor Ags. CD4+ Tregs induced from CD4+CD25− precursors (induced Tregs) also regulate immune responses in the periphery. However, which of these Tregs is a major impediment in generating antitumor CTL responses is not clear. We show that although the CD4+CD25+ subsets isolated from peripheral blood-derived lymphocytes do suppress the proliferation of CD4+CD25− effector T cells, they do not suppress the activation and expansion of the self but melanoma-associated, melanoma Ag-reactive T cell 1 (MART-1)27–35-specific CD8+ T cells stimulated by the respective peptide-loaded matured dendritic cells in vitro. The CD4+CD25− counterparts, in contrast, lead to the generation of CD25+ glucocorticoid-inducible TNFR+-Forkhead/winged helix transcription factor+ populations and efficiently suppress the activation and expansion of the MART-127–35 epitope-specific CTLs. Our data suggest that when CTL precursors are optimally stimulated, natural Tregs are not a formidable constraint toward generating a robust antitumor CTL response, but induced Tregs could be.

Melanoma in the elderly patient: relevance of the aging immune system

The rapidly expanding segment of the aging population with its rising incidence of cutaneous melanoma will present major challenges in therapeutic management. Immune strategies will be important in designing effective treatment of melanoma because it is a highly immunogenic tumor. Aging, however, is associated with dysregulation of the immune system and is likely to affect the success of melanoma treatment in the elderly population. This population represents an ideal in vivo model to study the effects of the aging immune system on the natural history of melanoma in the elderly. We review the epidemiology, histopathologic features, and treatment outcomes of elderly melanoma patients with reference to their immune function. Various components of the normal immune system are described, and the immune response to melanoma is recapitulated. Particular emphasis is placed on the growing understanding of the innate, adaptive, and regulatory arms of the aging immune system.

Presence of Low Dose of Fludarabine in Cultures Blocks Regulatory T Cell Expansion and Maintains Tumor-Specific Cytotoxic T Lymphocyte Activity Generated with Peripheral Blood Lymphocytes

Background: For tumor vaccine-based immunotherapy of cancer, the expansion of tumor antigen-specific cytotoxic T lymphocytes (CTL) in the patients by blocking induced regulatory T (Treg) cells is the most important objective now. Fludarabine (FLU), a known anticancer drug, has been shown to downregulate Treg cells in vivo in chronic leukemia patients. Melanoma tumor antigen Mart-127–35-specific CD8+ CTLs generated in vitrowith total peripheral blood lymphocytes (PBL) lose their activity within 14–21 days with concomitant expansion of Treg cells. When CD4+ cells are removed from PBL and CTL are generated with purified CD8+ cells, the CTL survive and maintain their activity for a significantly longer period. Methods: We used a low dose of FLU in the cultures in Mart-1-specific CTL generation assays with total PBL. Blood samples were taken from HLA-A2-positive melanoma patients and normal donors. Autologous matured dendritic cells pulsed with Mart-127–35 peptide were used to generate CTL responses using purified CD8+ cells or total PBL. Results: The presence of FLU in the cultures with PBL helped to generate a significantly higher number of antigen-specific CTLs as detected by Mart-1 HLA-A2 tetramer staining. Specificity of such CTLs was determined by IFN-γ secretion or by cytotoxicity against the target cells bearing the specific antigen. The presence of FLU stopped the expansion of IL-10-producing CD4+ Treg cells in the cultures with PBL. Analyses of expanded CD4+ cells isolated from PBL in vitro cocultures with FLU showed a Th1 type of function. Those cells secreted higher amounts of IFN-γ and very low levels of IL-10, or no IL-10 at all, upon restimulation. Conclusion: The observations of the study are as important for adaptive immunotherapy of cancer as they are for vaccine-based approaches.

Inhibition of c-Jun N-terminal kinase rescues influenza epitope-specific human cytolytic T lymphocytes from activation-induced cell death

Cytolytic T lymphocytes (CTL) play an important role in defense against viral infections. Following clonal expansion and effector functions, a vast majority of the antigen‐specific CTL undergoes programmed cell death to maintain homeostasis. We have shown earlier that melanoma epitope‐specific CTL are quite sensitive to activation‐induced cell death (AICD) even on the secondary encounter of the antigen. Excessive sensitivity of viral antigen‐specific CTL to AICD, however, would be counterproductive. It might be argued that although CTL for a “self” epitope might be more prone to AICD for maintaining self‐tolerance, viral antigen‐specific CTL are likely to be less sensitive to AICD. We show here that influenza matrix protein‐derived MP58–66 epitope‐specific CTL, activated in vitro and bearing a memory phenotype, are just as sensitive to AICD. The AICD in these CTL is not blocked by the pan‐caspase inhibitor benzyloxycarbonyl‐Val‐Ala‐Asp (OMe)‐fluoromethylketone or by soluble Ig‐Fc chimeras of the death receptors [Fas, TNF receptor (TNF‐R), TRAIL‐RI, TRAIL‐RII]. However, the MP58–66‐specific CTL can be rescued from AICD by the c‐jun‐N‐terminal kinase (JNK) inhibitor SP600125. These results have implications for immunotherapeutic intervention in rescuing viral epitope‐specific CTL from AICD.

Randomized double-blind placebo-controlled trial of celecoxib for oral mucositis in patients receiving radiation therapy for head and neck cancer

OBJECTIVES Oral mucositis (OM) is a painful complication of radiation therapy (RT) for head and neck cancer (H&NC). OM can compromise nutrition, require opioid analgesics and hospitalization for pain control, and lead to treatment interruptions. Based on the role of inflammatory pathways in OM pathogenesis, we investigated effect of cyclooxygenase-2 (COX-2) inhibition on severity and morbidity of OM. METHODS In this double-blind placebo-controlled trial, 40 H&NC patients were randomized to daily use of 200 mg celecoxib or placebo, for the duration of RT. Clinical OM, normalcy of diet, pain scores, and analgesic use were assessed 2-3 times/week by blinded investigators during the 6-7 week RT period, using validated scales. RESULTS Twenty subjects were randomized to each arm, which were similar with respect to tumor location, radiation dose, and concomitant chemotherapy. In both arms, mucositis and pain scores increased over course of RT. Intention-to-treat analyses demonstrated no significant difference in mean Oral Mucositis Assessment Scale (OMAS) scores at 5000 cGy (primary endpoint). There was also no difference between the two arms in mean OMAS scores over the period of RT, mean worst pain scores, mean normalcy of diet scores, or mean daily opioid medication use in IV morphine equivalents. There were no adverse events attributed to celecoxib use. CONCLUSIONS Daily use of a selective COX-2 inhibitor, during period of RT for H&NC, did not reduce the severity of clinical OM, pain, dietary compromise or use of opioid analgesics. These findings also have implications for celecoxib use in H&NC treatment regimens (NCT00698204).

Current status of chimeric antigen receptor engineered T cell-based and immune checkpoint blockade-based cancer immunotherapies

Adoptive cell therapies with chimeric antigen receptor (CAR) engineered T cells (CAR-T) and immune checkpoint inhibition (ICI)-based cancer immunotherapies have lately shown remarkable success in certain tumor types. CAR-T cell-based therapies targeting CD19 can now induce durable remissions as well as prolong disease-free survival of patients with CD19 positive treatment refractory B cell malignancies and ICI-based therapies with humanized monoclonal antibodies against the T cell inhibitory receptors CTLA-4 and PD-1 as well as against the PD-1 ligand, PD-L1, can now achieve durable remissions as well as prolongation of life of a sizeable fraction of patients with melanoma and Hodgkin’s lymphoma and non-small cell cancers. Most importantly, these immuno-therapeutic treatment modalities have raised the possibility of achieving long-term “containment” as well as “cures” for certain types of cancer. While this represents major advances in cancer immunotherapy, both modalities come with considerable toxicities, including fatalities. Although more work will be needed to bring CAR-T cell-based therapies to the bedside for most major cancers and a good deal more will be needed to make ICI—alone or in combination with other treatment modalities—work more consistently and across most major cancers, these two treatment modalities stand out as superb examples of successful translation of bench research to the bedside as well as represent real progress in the field of cancer immunotherapy.

Metastatic melanoma in the older patient: immunologic insights and treatment outcomes

Cutaneous melanoma (CM) is a highly curable skin cancer of melanocytes if diagnosed early. Unfortunately, its invasion into the deeper dermis increases the risk of it spreading to the lymph nodes and distant organs. Spread of metastatic melanoma (MM) to other organs is among one of the most dangerous conditions that is almost uniformly fatal for the majority of patients with the currently available treatment modalities. Since melanoma is an immunogenic tumor, developing novel immune strategies will continue to play a critical role in designing effective treatment modalities for those at high risk of recurrence and those with distant metastasis. While older age is believed to be a poor prognostic marker for CM, rapid expansion of the aging population and its projected increase in the coming decades is expected to result in a large number of elderly melanoma patients seeking treatment in all stages of disease. This will not only bring with it unique management challenges in this population, but also an increased burden on communities to provide financial and social resources. Comprehensive efforts will need to be directed towards early diagnosis, as well as developing safe and effective treatment. Renewed interest in the cancer immune surveillance theory coupled with recognition of aging-associated weaknesses in the immune system has put the spotlight on immunsenescence as a important risk factor for the rising incidence of CM in the aging population. Comprehensive assessment of the aging immune system might shed light, not only on weaknesses of individual components of the adaptive immune system, but also on the critical imbalances resulting from these weaknesses on anti-melanoma immunity. Identifying these imbalances might help harness novel immune-based treatment of MM in selected elderly patients. This article describes our experience of treating elderly patients with MM and the issues unique to them, with particular emphasis on insights into the aging immune system.