How I treat endocrine-dependent metastatic breast cancer.

Estrogen receptor-positive (ER+)/HER2-negative (HER2-), the so-called luminal-type breast cancer, is the most frequent subset, accounting for around 70% of all breast cancer cases. Endocrine therapy (ET) combined with cyclin-dependent kinases (CDK) 4/6 inhibitors is the standard first option in the management of advanced luminal breast cancer independently of disease extension. Classically, patients undergo multiple lines of ET ± targeted treatments until endocrine resistance occurs and palliative chemotherapy is proposed. Understanding endocrine resistance mechanisms and development of novel ET options is one of the main challenges in current clinical research. Another area of utmost interest is the improvement of post-endocrine therapeutic approaches. Among others, the development of antibody-drug conjugates (ADCs) is very promising, and some of these drugs will probably soon become a part of the therapeutic arsenal against this incurable disease. This review paper provides an overview of currently available treatment options in ER+/HER2- metastatic breast cancer and extensively discusses new approaches in late clinical development.

Health-related quality of life in patients with advanced melanoma treated with ipilimumab: prognostic implications and changes during treatment.

BACKGROUND: We have previously reported that the safety and efficacy of ipilimumab in real-world patients with metastatic melanoma were comparable to clinical trials. Few studies have explored health-related quality of life (HRQL) in real-world populations receiving checkpoint inhibitors. This study reports HRQL in real-world patients receiving ipilimumab and assesses the prognostic value of patient-reported outcome measures. PATIENTS AND METHODS: Ipi4 (NCT02068196) was a prospective, multicentre, interventional phase IV trial. Real-world patients (N = 151) with metastatic melanoma were treated with ipilimumab 3 mg/kg intravenously as labelled. HRQL was assessed by the European Organisation of Research and Treatment of Cancer Quality of Life Questionnaire at baseline and after 10-12 weeks. RESULTS: The European Organisation of Research and Treatment of Cancer Quality of Life Questionnaire was completed by 93% (141/151 patients) at baseline, and by 82% at 10-12 weeks. Poor performance status and elevated C-reactive protein (CRP) were associated with worse baseline HRQL. Clinically relevant and statistically significant deteriorations in HRQL from baseline to weeks 10-12 were reported (P <0.05). Baseline physical functioning [hazard ratio (HR) 1.96, P = 0.016], role functioning (HR 2.15, P <0.001), fatigue (HR 1.60, P = 0.030), and appetite loss (HR 1.76, P = 0.012) were associated with poorer overall survival independent of performance status, lactate dehydrogenase (LDH), and CRP. We further developed a prognostic model, combining HRQL outcomes with performance status, LDH, and CRP. This model identified three groups with large and statistically significant differences in survival. CONCLUSIONS: Systemic inflammation is associated with impaired HRQL. During treatment with ipilimumab, HRQL deteriorated significantly. Combining HRQL outcomes with objective risk factors provided additional prognostic information that may aid clinical decision making.

ICON: a randomized phase IIb study evaluating immunogenic chemotherapy combined with ipilimumab and nivolumab in patients with metastatic hormone receptor positive breast cancer.

BACKGROUND: Immunotherapy with checkpoint inhibitors (CPI) targeting PD-1 or CTLA-4 has emerged as an important treatment modality for several cancer forms. In hormone receptor positive breast cancer (HR + BC), this therapeutic approach is largely unexplored. We have started a clinical trial, ICON (CA209-9FN), evaluating CPI combined with selected chemotherapy in patients with metastatic HR + BC. The tumor lymphocyte infiltration is predictive for the effect of chemotherapy in BC. In ICON, we use anthracycline, which are considered as "immunogenic" chemotherapy, and low-dose cyclophosphamide, which has been reported to counter immunosuppressive cells. METHODS: ICON is a randomized exploratory phase IIb study evaluating the safety and efficacy of combining nivolumab (nivo; anti-PD-1) and ipilimumab (ipi; anti-CTLA-4) with chemotherapy in subjects with metastatic HR + BC. Primary objectives are aassessment of toxicity and progression-free survival. The trial will enrol 75 evaluable subjects, randomized 2:3 into two arms (A:B). Patients in Arm A receive only chemotherapy, i.e. pegylated liposomal doxorubicin (PLD 20 mg/m2 intravenously every 2nd week) + cyclophosphamide (cyclo; 50 mg per day, first 2 weeks in each 4 week cycle). Patients in Arm B receive PLD + cyclo + ipilimumab (1 mg intravenously every 6th week) + nivolumab (240 mg intravenously every 2nd week). Patients in arm A will be offered ipi + nivo after disease progression. DISCUSSION: ICON is among the first clinical trials combining chemotherapy with PD-1 and CTLA-4 blockade, and the first in BC. There is a strong preclinical rationale for exploring if anthracyclines, which are considered to induce immunogenic cell death, synergize with CPI, and for combining PD-1 and CTLA-4 blockade, as these checkpoints are important in different phases of the immune response. If the ICON trial suggests acceptable safety and provide a signal of clinical efficacy, further studies are warranted. The cross-over patients from Arm A receiving ipilimumab/nivolumab without concomitant chemotherapy represent the first BC cohort receiving this therapy. The ICON trial includes a series of translational sub-projects addressing clinically important knowledge gaps. These studies may uncover biomarkers or mechanisms of efficacy and resistance, thereby informing the development of novel combinatory regimes and of personalised biomarker-based therapy. Trial registration NCT03409198, Jan 24th 2018; https://clinicaltrials.gov/ct2/show/record/NCT03409198.

ALICE: a randomized placebo-controlled phase II study evaluating atezolizumab combined with immunogenic chemotherapy in patients with metastatic triple-negative breast cancer.

BACKGROUND: Immunotherapy with checkpoint inhibitors (CI) represents an important novel development in cancer treatment. Metastatic triple-negative breast cancer (mTNBC) is incurable, with a median survival of only ~ 13 months. We have initiated the randomized placebo-controlled phase IIb study ALICE, evaluating PD-L1 blockade combined with immunogenic chemotherapy in mTNBC patients (n = 75). Intriguingly, the host immune response is strongly predictive for the effect of chemotherapy in mTNBC. In the ALICE trial, we release the brake on the immune response by use of atezolizumab, an inhibitory antibody against PD-L1. We utilize anthracyclines, shown to trigger the immune system, and low-dose cyclophosphamide, which has been reported to counter immunosuppressive cells. METHODS: ALICE is a randomized, double-blind, placebo-controlled exploratory phase II study evaluating the safety and efficacy of atezolizumab when combined with immunogenic chemotherapy in subjects with mTNBC. The trial will enroll 75 evaluable subjects, randomized 2:3 into two arms (A:B). The patients receive identical chemotherapy, i.e. pegylated liposomal doxorubicin (PLD 20 mg/m2 intravenously every 2nd week) + cyclophosphamide (50 mg per day, first 2 weeks in each 4 week cycle). Patients in arm A receive placebo, while patients in arm B receive atezolizumab. The primary objectives are assessment of toxicity and progression-free survival. The secondary objectives include overall survival, tumor response rate, clinical benefit rate, patient reported outcomes, biomarkers and assessment of tumor-immune evolution during therapy. DISCUSSION: The question of how CI should be combined with chemotherapy, is a key challenge facing the field. There is a strong preclinical rationale for exploring if anthracyclines, which are considered to induce immunogenic cell death, synergize with PD-L1 blockade, and if low-dose cyclophosphamide counters tumor tolerance. However, the data from patients is as yet very limited, and the clinical evaluation of these hypotheses is among the key objectives in the ALICE trial. The study includes extensive biobanking and translational sub-projects, also addressing other clinically important questions. These analyses may uncover mechanisms of drug efficacy or tumor resistance, and identify biomarkers allowing personalized therapy. If the trial suggests acceptable safety of the ALICE therapy and provide a signal of clinical efficacy, further studies are warranted. Trial registration NCT03164993, May 24th 2017; https://clinicaltrials.gov/ct2/show/record/NCT03164993.

Inclusion of an IgG1-Fc spacer abrogates efficacy of CD19 CAR T cells in a xenograft mouse model.

Cancer therapy with T cells expressing chimeric antigen receptors (CARs) has produced remarkable clinical responses in recent trials, but also severe side effects. Whereas most protocols use permanently reprogrammed T cells, we have developed a platform for transient CAR expression by mRNA electroporation. This approach may be useful for safe clinical testing of novel receptors, or when a temporary treatment period is desirable. Herein, we investigated therapy with transiently redirected T cells in vitro and in a xenograft mouse model. We constructed a series of CD19-specific CARs with different spacers and co-stimulatory domains (CD28, OX40 or CD28-OX40). The CAR constructs all conferred T cells with potent CD19-specific activity in vitro. Unexpectedly, the constructs incorporating a commonly used IgG1-CH2CH3 spacer showed lack of anti-leukemia activity in vivo and induced severe, partly CD19-independent toxicity. By contrast, identical CAR constructs without the CH2-domain eradicated leukemia in vivo, without notable toxicity. Follow-up studies demonstrated that the CH2CH3-spacer bound soluble mouse Fcγ-receptor I and mediated off-target T-cell activation towards murine macrophages. Our findings highlight the importance of non-signalling CAR elements and of in vivo studies. Finally, the results show that transiently redirected T cells control leukemia in mice and support the rationale for developing an mRNA-CAR platform.

Phase I/II trial of melanoma therapy with dendritic cells transfected with autologous tumor-mRNA.

We have developed an individualized melanoma vaccine based on transfection of autologous dendritic cells (DCs) with autologous tumor-mRNA. Dendritic cells loaded with complete tumor-mRNA may generate an immune response against a broad repertoire of antigens, including unique patient-specific antigens. The purpose of the present phase I/II trial was to evaluate the feasibility and safety of the vaccine, and the ability of the DCs to elicit T-cell responses in melanoma patients. Further, we compared intradermal (i.d.) and intranodal (i.n.) vaccine administration. Twenty-two patients with advanced malignant melanoma were included, each receiving four weekly vaccines. Monocyte-derived DCs were transfected with tumor-mRNA by electroporation, matured and cryopreserved. We obtained successful vaccine production for all patients elected. No serious adverse effects were observed. A vaccine-specific immune response was demonstrated in 9/19 patients evaluable by T-cell assays (T-cell proliferation/interferon-gamma ELISPOT) and in 8/18 patients evaluable by delayed-type hypersensitivity (DTH) reaction. The response was demonstrated in 7/10 patients vaccinated intradermally and in 3/12 patients vaccinated intranodally. We conclude that immuno-gene-therapy with the described DC-vaccine is feasible and safe, and that the vaccine can elicit in vivo T-cell responses against antigens encoded by the transfected tumor-mRNA. The response rates do not suggest an advantage in applying i.n. vaccination.

Immunotherapy with allotumour mRNA-transfected dendritic cells in androgen-resistant prostate cancer patients.

Here, we present results from a clinical trial employing a new vaccination method using dendritic cells (DCs) transfected with mRNA from allogeneic prostate cancer cell lines (DU145, LNCaP and PC-3). In all, 20 patients were enrolled and 19 have completed vaccination. Each patient received at least four weekly injections with 2 x 10(7) transfected DCs either intranodally or intradermally. Safety and feasibility of vaccination were determined. Immune responses were measured as delayed-type hypersensitivity and by in vitro immunoassays including ELISPOT and T-cell proliferation in pre- and postvaccination peripheral blood samples. Serum prostate-specific antigen (PSA) levels and bone scans were monitored. No toxicity or serious adverse events related to vaccinations were observed. A total of 12 patients developed a specific immune response to tumour mRNA-transfected DCs. In total, 13 patients showed a decrease in log slope PSA. This effect was strengthened by booster vaccinations. Clinical outcome was significantly related to immune responses (n = 19, P = 0.002, r = 0.68). Vaccination with mRNA-transfected DCs is safe and results in cellular immune responses specific for antigens encoded by mRNA derived from the prostate cancer cell lines. The observation that in some patients vaccination affected the PSA level suggests that this approach may become useful as a treatment modality for prostate cancer patients.

Resting small B cells present endogenous immunoglobulin variable-region determinants to idiotope-specific CD4(+) T cells in vivo.

Antigenic determinants localized within the highly diversified V-regions of Ig are called idiotopes (Id). Processed Id-peptides can be presented on MHC class II molecules to CD4(+) T cells. If B cells present their endogenous Id-peptides, T cell activation could occur in the absence of nominal antigen, a potentially important process in T-B cooperation and immune regulation. To test this idea, we used mice made transgenic for a lambda2 L-chain (Id(+) mice). Another transgenic mouse strain expresses TCR transgenes with specificity for the Id (lambda2), presented on MHC class II molecules. When highly purified sorted Id(+) B cells and Id-specific T cells were sequentially injected into MHC syngeneic SCID host, T cell became blastoid, CD69(+) and proliferated. To exclude any role of host APC, MHC incompatible Rag2(- / -) mice (H-2(b)) were used as recipients for the Id(+) B and Id-specific T cells, with similar results. Exposure to extracellular Id(+) immunoglobulin (Ig) was not sufficient for Id priming of B cells in vivo, highlighting the preferential presentation of Id peptides derived from endogenous Ig, by B cells. The results suggest that B cells presenting Id self-peptides generated by V(D)J recombinations or somatic mutations may directly stimulate T cell in vivo in the absence of conventional antigen.