Kristine Rinn

Generation of T-Cell Immunity to the HER-2/neu Protein After Active Immunization With HER-2/neu Peptide–Based Vaccines

PURPOSE The HER-2/neu protein is a nonmutated tumor antigen that is overexpressed in a variety of human malignancies, including breast and ovarian cancer. Many tumor antigens, such as MAGE and gp100, are self-proteins; therefore, effective vaccine strategies must circumvent tolerance. We hypothesized that immunizing patients with subdominant peptide epitopes derived from HER-2/neu, using an adjuvant known to recruit professional antigen-presenting cells, granulocyte-macrophage colony-stimulating factor, would result in the generation of T-cell immunity specific for the HER-2/neu protein. PATIENTS AND METHODS Sixty-four patients with HER-2/neu-overexpressing breast, ovarian, or non-small-cell lung cancers were enrolled. Vaccines were composed of peptides derived from potential T-helper epitopes of the HER-2/neu protein admixed with granulocyte-macrophage colony-stimulating factor and administered intradermally. Peripheral-blood mononuclear cells were evaluated at baseline, before vaccination, and after vaccination for antigen-specific T-cell immunity. Immunologic response data are presented on the 38 subjects who completed six vaccinations. Toxicity data are presented on all 64 patients enrolled. RESULTS Ninety-two percent of patients developed T-cell immunity to HER-2/neu peptides (stimulation index, 2.1 to 59) and 68% to a HER-2/neu protein domain (stimulation index range, 2 to 31). Epitope spreading was observed in 84% of patients and significantly correlated with the generation of a HER-2/neu protein-specific T-cell immunity (P =.03). At 1-year follow-up, immunity to the HER-2/neu protein persisted in 38% of patients. CONCLUSION The majority of patients with HER-2/neu-overexpressing cancers can develop immunity to both HER-2/neu peptides and protein. In addition, the generation of protein-specific immunity, after peptide immunization, was associated with epitope spreading, reflecting the initiation of an endogenous immune response. Finally, immunity can persist after active immunizations have ended.

Pre-existent immunity to the HER-2/neu oncogenic protein in patients with HER-2/neu overexpressing breast and ovarian cancer

Immunomodulatory strategies, such as antibody therapy and cancer vaccines, are increasingly being considered as potential adjuvant therapies in patients with advanced stage breast cancer to either treat minimal residual disease or prevent relapse. However, little is known concerning the incidence and magnitude of the pre-existent breast cancer specific immune response in this patient population. Using the HER-2/neu oncogenic protein as a model, a well-defined tumor antigen in breast cancer, we questioned whether patients with advanced stage HER-2/neu overexpressing breast and ovarian cancers (III/IV) had evidence of pre-existent immunity to HER-2/neu. Forty-five patients with stage III or IV HER-2/neu overexpressing breast or ovarian cancer were evaluated for HER-2/neu specific T cell and antibody immunity. Patients enrolled had not received immunosuppressive chemotherapy for at least 30 days (median 5 months, range 1–75 months). All patients were documented to be immune competent prior to entry by DTH testing using a skin test anergy battery. Five of 45 patients (11%) were found to have a significant HER-2/neu specific T cell response as defined by a stimulation index ≥ 2.0 (range 2.0–7.9). None of eight patients who were HLA-A2 had a detectable IFNγ secreting T-cell precursor frequency to a well-defined HER-2/neu HLA-A2 T cell epitope, p369-377. Three of 45 patients (7%) had detectable HER-2/neu specific IgG antibodies, range 1.2–8.9 μg/ml. These findings suggest that patients with advanced stage HER-2/neu overexpressing breast and ovarian cancer can mount a T cell and/or antibody immune response to their tumor. However, in the case of the HER-2/neu antigen, the pre-existent tumor specific immune response is found only in a minority of patients.

[Tc-99m]-sestamibi uptake and washout in locally advanced breast cancer are correlated with tumor blood flow

OBJECTIVES To determine the influence of breast tumor blood flow on MIBI kinetics, we compared MIBI uptake and washout to [O-15]-water PET estimates of blood flow in patients with locally advanced breast cancer. METHODS Prior to therapy, 37 patients underwent MIBI and [O-15]-water PET imaging; 22/37 also had MIBI washout analysis. Twenty-five patients underwent serial imaging over the course of chemotherapy. RESULTS MIBI uptake and blood flow had a significant positive correlation pre-therapy. The change in MIBI uptake over the course of therapy also correlated with the change in blood flow. The half-time of MIBI washout inversely correlated with blood flow, indicating faster MIBI washout with higher blood flow. CONCLUSIONS Blood flow strongly influences early MIBI uptake and can be a factor affecting the rate of MIBI washout in breast tumors. We present a model of MIBI kinetics in tumors which forms a hypothesis for further mechanistic studies of MIBI uptake and washout in breast cancer.

A Phase I Trial of Immunotherapy with Lapuleucel-T (APC8024) in Patients with Refractory Metastatic Tumors that Express HER-2/neu

Purpose: This study aimed to evaluate the safety of, immune response induced by, and efficacy of treatment with lapuleucel-T (APC8024) in patients with HER-2/neu–expressing tumors. Lapuleucel-T is an investigational active immunotherapy product consisting of autologous peripheral blood mononuclear cells, including antigen presenting cells, which are cultured ex vivo with BA7072, a recombinant fusion antigen consisting of portions of the intracellular and extracellular regions of HER-2/neu linked to granulocyte-macrophage colony-stimulating factor. Experimental Design: Patients with metastatic breast, ovarian, or colorectal cancer whose tumors expressed HER-2 were eligible. Patients underwent leukapheresis in week 0 and received lapuleucel-T infusions in weeks 0, 2, and 4. Patients who achieved a partial response or had stable disease through week 48 were eligible for re-treatment using the same protocol and dose as their initial treatment. Results: Eighteen patients were enrolled and treated. Patients showed an immune response to the immunizing antigen (BA7072) at week 8 compared with week 0 as measured by T lymphocyte proliferation and IFN-γ enzyme-linked immunospot assay. Therapy was well tolerated. The majority (94.7%) of adverse events associated with treatment were grade 1 or 2. Two patients experienced stable disease lasting >48 weeks. Conclusions: Autologous active cellular immunotherapy with lapuleucel-T stimulated an immune response specific to the immunizing antigen and seemed to be well tolerated. Further clinical studies to assess the clinical benefit for patients with HER/2-neu–expressing breast, ovarian, and colorectal cancer are warranted. (Clin Cancer Res 2009;15(18):5937–44)

SWOG S0221: A Phase III Trial Comparing Chemotherapy Schedules in High-Risk Early-Stage Breast Cancer

PURPOSE To determine the optimal dose and schedule of anthracycline and taxane administration as adjuvant therapy for early-stage breast cancer. PATIENTS AND METHODS A 2 × 2 factorial design was used to test two hypotheses: (1) that a novel continuous schedule of doxorubicin-cyclophosphamide was superior to six cycles of doxorubicin-cyclophosphamide once every 2 weeks and (2) that paclitaxel once per week was superior to six cycles of paclitaxel once every 2 weeks in patients with node-positive or high-risk node-negative early-stage breast cancer. With 3,250 patients, a disease-free survival (DFS) hazard ratio of 0.82 for each randomization could be detected with 90% power with two-sided α = .05. Overall survival (OS) was a secondary outcome. RESULTS Interim analyses crossed the futility boundaries for demonstrating superiority of both once-per-week regimens and once-every-2-weeks regimens. After a median follow-up of 6 years, a significant interaction developed between the two randomization factors (DFS P = .024; OS P = .010) in the 2,716 patients randomly assigned in the original design, which precluded interpretation of the two factors separately. Comparing all four arms showed a significant difference in OS (P = .040) but not in DFS (P = .11), with all treatments given once every 2 weeks associated with the highest OS. This difference in OS seemed confined to patients with hormone receptor-negative/human epidermal growth factor receptor 2 (HER2) -negative tumors (P = .067), with no differences seen with hormone receptor-positive/HER2-negative (P = .90) or HER2-positive tumors (P = .40). CONCLUSION Patients achieved a similar DFS with any of these regimens. Subset analysis suggests the hypothesis that once-every-2-weeks dosing may be best for patients with hormone receptor-negative/HER2-negative tumors.

Immunotherapeutic approaches for the treatment of breast cancer.

The application of immunotherapeutic principlesto the treatment and prevention of breast cancer is arelatively new undertaking. Although cytokine infusions,cancer vaccines, and T cell therapy have been extensively studied in solid tumors such asmelanoma and renal cell carcinoma, the therapeuticefficacy of these approaches is not well explored inbreast cancer. The recent definition of tumor-specific immunity in breast cancer patients and theidentification of several breast cancer antigens hasgenerated enthusiasm for the application of immune-basedtherapies to the treatment of breast malignancies. In general, immunotherapies can be consideredeither non-specific, such as a general immunomodulator(e.g., a cytokine), or tumor-specific (e.g., a vaccinethat targets breast cancer tumor antigens). This review describes three major immunotherapeuticstrategies that have the potential to enhance orgenerate an anti-breast cancer T cell immune response:(i) cytokine therapy; (ii) cancer vaccines; and (iii) T cell therapy, and explores how each strategyhas been applied to the treatment of breastcancer.

Delayed type hypersensitivity response to recall antigens does not accurately reflect immune competence in advanced stage breast cancer patients

The development of delayed-type hypersensitivity (DTH) response to recall antigens has long been utilized as a measure of immune competence. It is assumed that because patients with advanced stage cancers exhibit multiple immune system defects they may not be responsive to immunization. We pre-selected patients with advanced HER-2/neu (HER2) overexpressing breast and ovarian cancers for enrolment into a phase I trial designed to evaluate the immunogenicity of a HER2 peptide vaccine based on the patients immune competence as assessed by DTH skin testing to common recall antigens (Multitest CMI, Institut Merieux, Lyon, France). At the time of a positive DTH response to tetanus toxoid (tt) peripheral blood was obtained to measure T cell responses to tt. Of 53 patients evaluated, 38 (72%) were not anergic. Among the 15 (28%) who were, seven patients with advanced stage breast cancer were re-tested a median of 26 days (range 12–150 days) after receiving a tt booster vaccination. Five of the seven had positive DTH responses when re-challenged with tt and six had peripheral blood tetanus specific T cell response with stimulation index > 2.0. Thus, the majority of patients studied with advanced stage breast or ovarian cancer were able to mount a DTH response to common recall antigens. Moreover, a negative response by DTH testing to a battery of common recall antigens was not a reflection of the breast cancer patients ability to mount a cell-mediated immune response to a vaccinated antigen, tt.

Antigen-specific recall urticaria to a peptide-based vaccine

Recall urticaria (RU) is a localized urticarial response that occurs at a site of previous antigen injection on reexposure to that antigen at a remote site.1 The response is rare and typically associated with allergy immune therapies. The mechanism for RU is poorly understood, but possibilities include increased accumulation and degranulation of mast cells at the site of previous allergy injections.1 RU has not been described in the setting of peptide-based vaccines. In recent years several immunogenic proteins associated with human malignancies have been identified, allowing the development of antigen-specific cancer vaccines.2 Our group has focused on the HER-2/neu oncoprotein as a tumor antigen. HER-2/neu is a cancer-related protein that is overexpressed in 30% of breast and ovarian cancers. Studies in animal models have demonstrated that HER-2/neu peptide-based vaccines, mixed with GM-CSF as an adjuvant, effectively generate HER2/neu-specific immunity.3 A phase-I trial of HER-2/neu peptide-based vaccines was approved by both the University of Washington Human Subjects Division and the United States Food and Drug Administration. Patients with stable stage III or IV breast, ovarian, or non-small cell lung cancers were vaccinated monthly for 6 months. GM-CSF was used as a vaccine adjuvant. This case report describes 1 patient in whom RU developed 30 days after the last vaccination.

S0221: Comparison of two schedules of paclitaxel as adjuvant therapy for breast cancer.

CRA1008 Background: S0221 is a SWOG-coordinated phase III adjuvant chemotherapy intergroup trial in node-positive and high-risk node-negative operable breast cancer which hypothesized that 1) the weekly AC+G regimen is superior to ddAC x 6 and 2) 12 weeks of weekly paclitaxel (wP) is superior to q 2 week paclitaxel x 6 (ddP). METHODS Between December 2003 and November 2010, 2,716 patients were randomized in a 2 x 2 factorial design to 1) AC+G vs ddAC and 2) P 80 mg/m2/week x 12 vs P 175 mg/m2 q 2 weeks x 6. If there was no significant interaction between the factors, the trial was powered to find a disease-free survival hazard ratio (HR) ≤ 0.82 for weekly vs q 2 week for each factor. At the first interim analysis, the AC randomization was halted for futility, and S0221 was closed to accrual 10 November 2010. S0221 reopened 15 December 2010, after which time all patients received 4 cycles of ddAC and randomization to P weekly x 12 and ddP x 6 continued. Accrual halted at a total of 3,294 in January 2012. RESULTS By September 7, 2012, 487 events and 340 deaths had occurred, prompting the third planned interim analysis. The Data Safety and Monitoring Committee recommended reporting the results since the futility boundary was crossed. A Cox model adjusting for the AC arms had a HR = 1.08 (95% CI 0.90-1.28; p=0.42), with the 99.5% CI excluding the original alternative hypothesis that the HR=0.82. There was no significant interaction of the two factors. Estimated 5-year progression-free survivals were 82% for weekly P and 81% for ddP. Toxicity data were available for 1,385 patients treated with ddP and 1,367 treated with weekly P. Grade 5 toxicity occurred in 4 patients on ddP and 2 on weekly P. Percent grade 3-4 toxicity per arm are shown in the Table. CONCLUSIONS Either ddPx6 or weekly P x 12 are acceptable schedules of P administration. The differences in leukopenia likely reflect ascertainment bias against weekly P. If this is accepted, weekly P x 12 produces less overall toxicity than 6 cycles of ddP. Support: NCI grants CA32102, CA38926, CA21115, CA21076, CA77597, CA25224, CA77202, CCSRI15469, and Amgen, Inc. CLINICAL TRIAL INFORMATION NCT00070564. [Table: see text].

Phase II Feasibility Study of a Weight Loss Intervention in Female Breast and Colorectal Cancer Survivors (SWOG S1008).

This study aimed to test the feasibility of a 12‐month weight loss intervention using telephone‐based counseling plus community‐situated physical activity (PA) in female breast cancer (BC) and colorectal cancer (CRC) survivors.