Phase I trial of the DLL3/CD3 bispecific T-cell engager BI 764532 in DLL3-positive small-cell lung cancer and neuroendocrine carcinomas.

Poorly differentiated neuroendocrine carcinomas such as small-cell lung cancer (SCLC) have poor survival and high relapse rates. DLL3 is found on these carcinomas and has become a target of increasing interest in recent years. The bispecific DLL3/CD3 T-cell engager BI 764532 has been shown to induce complete tumor regression in a human T cell-engrafted mouse model. Here, we describe the study design of a first-in-human, phase I, multicenter, open-label, non-randomized, dose-escalation study in patients with SCLC or other DLL3-positive neuroendocrine carcinomas. The study will determine the maximum tolerated dose and evaluate safety, tolerability, pharmacokinetics and preliminary efficacy of BI 764532 monotherapy.

DLL3 is a protein involved in development of the embryo during pregnancy. It has also been found on the surface of cells involved in the development of certain types of lung cancer and other tumors. The T-cell engager BI 764532 binds to DLL3 and cells of the immune system simultaneously, resulting in the death of tumor cells. Here we describe the rationale for, and design of, a clinical study of BI 764532 in patients with small-cell lung cancer and other tumors containing DLL3. The aim of the study is to find the highest acceptable dose of BI 764532 that can be tolerated by patients, and explore the safety and efficacy of BI 764532. Clinical Trial Registration: NCT04429087 (ClinicalTrials.gov).

Rationale and Design for the LUME-Colon 1 Study: A Randomized, Double-Blind, Placebo-Controlled Phase III Trial of Nintedanib Plus Best Supportive Care Versus Placebo Plus Best Supportive Care in Patients With Advanced Colorectal Cancer Refractory to Standard Treatment.

BACKGROUND: Clinical studies of antivascular endothelial growth factor (anti-VEGF) agents have demonstrated that angiogenesis is critical to colorectal cancer (CRC) tumor growth and metastasis. Nintedanib is a triple angiokinase inhibitor of VEGF, platelet-derived growth factor, and fibroblast growth factor signaling. Nintedanib, combined with docetaxel, has been approved in the European Union for the treatment of patients with non-small-cell lung cancer with adenocarcinoma tumor histologic type after first-line chemotherapy. The objective of the present study (1199.52; clinicaltrials.gov identifier NCT02149108; LUME-Colon 1) is to evaluate the efficacy and safety of nintedanib plus best supportive care (BSC) in patients with advanced colorectal cancer refractory to standard chemotherapy regimens and biologic agents. PATIENTS AND METHODS: A total of 764 patients worldwide will be randomized 1:1 to receive either nintedanib 200 mg twice daily plus BSC or placebo plus BSC in 21-day courses until disease progression, undue toxicity, or withdrawal of informed consent. The primary endpoints are progression-free survival (PFS) and overall survival (OS). The secondary endpoints are the objective tumor response and disease control. PFS and OS will be evaluated using a log-rank test to determine the effect of nintedanib independently at the 2-sided α-level of 0.05. Other assessments will include the frequency and severity of adverse events and changes in laboratory parameters to measure the safety, health-related quality of life, and pharmacogenomic analyses, focusing on exploring the predictive biomarkers and drug-resistance mechanisms. The results are expected in 2016.

Vascular effects, efficacy and safety of nintedanib in patients with advanced, refractory colorectal cancer: a prospective phase I subanalysis.

BACKGROUND: Nintedanib is a potent, oral angiokinase inhibitor that targets VEGF, PDGF and FGF signalling, as well as RET and Flt3. The maximum tolerated dose of nintedanib was evaluated in a phase I study of treatment-refractory patients with advanced solid tumours. In this preplanned subanalysis, the effect of nintedanib on the tumour vasculature, along with efficacy and safety, was assessed in 30 patients with colorectal cancer (CRC). METHODS: Patients with advanced CRC who had failed conventional treatment, or for whom no therapy of proven efficacy existed, were treated with nintedanib ranging from 50-450 mg once-daily (n = 14) or 150-250 mg twice-daily (n = 16) for 28 days. After a 1-week rest, further courses were permitted in the absence of progression or undue toxicity. The primary objective was the effect on the tumour vasculature using dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and expressed as the initial area under the DCE-MRI contrast agent concentration-time curve after 60 seconds (iAUC60) or the volume transfer constant between blood plasma and extravascular extracellular space (Ktrans). RESULTS: Patients received a median of 4.0 courses (range: 1-13). Among 21 evaluable patients, 14 (67%) had a ≥40% reduction from baseline in Ktrans and 13 (62%) had a ≥40% decrease from baseline in iAUC60, representing clinically relevant effects on tumour blood flow and permeability, respectively. A ≥40% reduction from baseline in Ktrans was positively associated with non-progressive tumour status (Fisher's exact: p = 0.0032). One patient achieved a partial response at 250 mg twice-daily and 24 (80%) achieved stable disease lasting ≥8 weeks. Time to tumour progression (TTP) at 4 months was 26% and median TTP was 72.5 days (95% confidence interval: 65-114). Common drug-related adverse events (AEs) included nausea (67%), vomiting (53%) and diarrhoea (40%); three patients experienced drug-related AEs ≥ grade 3. Four patients treated with nintedanib once-daily had an alanine aminotransferase and/or aspartate aminotransferase increase ≥ grade 3. No increases > grade 2 were seen in the twice-daily group. CONCLUSIONS: Nintedanib modulates tumour blood flow and permeability in patients with advanced, refractory CRC, while achieving antitumour activity and maintaining an acceptable safety profile.

Effect of small angiokinase inhibitor nintedanib (BIBF 1120) on QT interval in patients with previously untreated, advanced renal cell cancer in an open-label, phase II study.

PURPOSE: Some targeted anticancer agents are associated with serious ventricular tachyarrhythmias, which may be predicted by electrocardiographic evaluation of drug-related QT prolongation. We studied the effects of nintedanib (BIBF 1120; an oral, triple angiokinase inhibitor targeting vascular endothelial growth factor, fibroblast growth factor, and platelet-derived growth factor receptors) on the QT interval in patients with renal cell carcinoma (RCC) participating in an open-label phase II trial. METHODS: Treatment-naïve, adult patients with unresectable/metastatic, clear cell RCC received nintedanib 200 mg twice daily. QT intervals were evaluated at baseline (day -1), on day 1 (after the first dose), and on day 15 (steady state) by 12-lead electrocardiograms (ECGs) performed in triplicate. Pharmacokinetic sampling was also undertaken. RESULTS: Among 64 evaluable patients, the upper limits of the 2-sided 90 % confidence intervals for the adjusted mean time-matched changes in QTcF interval (corrected for heart rate by Fridericia's method) from baseline to day 1 and 15 (primary ECG endpoint) were well below the regulatory threshold of 10 ms at all times. No relationship between nintedanib exposure and change from baseline in QTcF was seen. Nintedanib was generally well tolerated with no drug-related cardiovascular adverse events. CONCLUSION: Nintedanib administered at 200 mg twice daily was not associated with clinically relevant QT prolongation.

Tumor stroma engraftment of gene-modified mesenchymal stem cells as anti-tumor therapy against ovarian cancer.

BACKGROUND AIMS: Many ovarian cancers originate from ovarian surface epithelium, where they develop from cysts intermixed with stroma. The stromal layer is critical to the progression and survival of the neoplasm and consequently is recruited into the tumor microenvironment. METHODS: Using both syngeneic mouse tumors (ID8-R) and human xenograft (OVCAR3, SKOV3) tumor models, we first confirmed that intraperitoneally injected circulating mesenchymal stem cells (MSCs) could target, preferentially engraft and differentiate into α-smooth muscle actin-positive myofibroblasts, suggesting their role as "reactive stroma" in ovarian carcinoma development and confirming their potential as a targeted delivery vehicle for the intratumoral production of interferon-ß (IFN-ß). Mice with ovarian carcinomas then received weekly intraperitoneal injections of IFN-ß expressing MSCs. RESULTS: Intraperitoneal injections of IFN-ß expressing MSCs resulted in complete eradication of tumors in 70% of treated OVCAR3 mice (P = 0.004) and an increased survival of treated SKOV3 mice compared with controls (P = 0.01). Similar tumor growth control was observed using murine IFN-ß delivered by murine MSCs in ID8-R ovarian carcinoma. As a potential mechanism of tumor killing, MSCs produced IFN-ß-induced caspase-dependent tumor cell apoptosis. CONCLUSIONS: Our results demonstrate that ovarian carcinoma engrafts MSCs to participate in myofibrovascular networks and that IFN-ß produced by MSCs intratumorally modulates tumor kinetics, resulting in prolonged survival.

Mesenchymal stem cells in cancer: tumor-associated fibroblasts and cell-based delivery vehicles.

Recent evidence suggests that mesenchymal stem cells (MSC) selectively home to tumors, where they contribute to the formation of tumor-associated stroma. This effect can be opposed by genetically modifying MSC to produce high levels of anti-cancer agents that blunt tumor growth kinetics and inhibit the growth of tumors in situ. In this review article, we describe the biological properties of MSC within the tumor microenvironment and discuss the potential use of MSC and other bone marrow-derived cell populations as delivery vehicles for antitumor proteins.

Human bone marrow-derived mesenchymal stem cells in the treatment of gliomas.

The poor survival of patients with human malignant gliomas relates partly to the inability to deliver therapeutic agents to the tumor. Because it has been suggested that circulating bone marrow-derived stem cells can be recruited into solid organs in response to tissue stresses, we hypothesized that human bone marrow-derived mesenchymal stem cells (hMSC) may have a tropism for brain tumors and thus could be used as delivery vehicles for glioma therapy. To test this, we isolated hMSCs from bone marrow of normal volunteers, fluorescently labeled the cells, and injected them into the carotid artery of mice bearing human glioma intracranial xenografts (U87, U251, and LN229). hMSCs were seen exclusively within the brain tumors regardless of whether the cells were injected into the ipsilateral or contralateral carotid artery. In contrast, intracarotid injections of fibroblasts or U87 glioma cells resulted in widespread distribution of delivered cells without tumor specificity. To assess the potential of hMSCs to track human gliomas, we injected hMSCs directly into the cerebral hemisphere opposite an established human glioma and showed that the hMSCs were capable of migrating into the xenograft in vivo. Likewise, in vitro Matrigel invasion assays showed that conditioned medium from gliomas, but not from fibroblasts or astrocytes, supported the migration of hMSCs and that platelet-derived growth factor, epidermal growth factor, or stromal cell-derived factor-1alpha, but not basic fibroblast growth factor or vascular endothelial growth factor, enhanced hMSC migration. To test the potential of hMSCs to deliver a therapeutic agent, hMSCs were engineered to release IFN-beta (hMSC-IFN-beta). In vitro coculture and Transwell experiments showed the efficacy of hMSC-IFN-beta against human gliomas. In vivo experiments showed that treatment of human U87 intracranial glioma xenografts with hMSC-IFN-beta significantly increase animal survival compared with controls (P < 0.05). We conclude that hMSCs can integrate into human gliomas after intravascular or local delivery, that this engraftment may be mediated by growth factors, and that this tropism of hMSCs for human gliomas can be exploited to therapeutic advantage.

Mesenchymal stem cells: potential precursors for tumor stroma and targeted-delivery vehicles for anticancer agents.

BACKGROUND: High concentrations of interferon beta (IFN-beta) inhibit malignant cell growth in vitro. However, the therapeutic utility of IFN-beta in vivo is limited by its excessive toxicity when administered systemically at high doses. Mesenchymal stem cells (MSC) can be used to target delivery of agents to tumor cells. We tested whether MSC can deliver IFN-beta to tumors, reducing toxicity. METHODS: Human MSC were transduced with an adenoviral expression vector carrying the human IFN-beta gene (MSC-IFN-beta cells). Flow cytometry was used to measure tumor cell proliferation among in vitro co-cultures of MSC-IFN-beta cells and human MDA 231 breast carcinoma cells or A375SM melanoma cells. We used a severe combined immunodeficiency mouse xenograft model (4-10 mice per group) to examine the effects of injected MSC-IFN-beta cells and human recombinant IFN-beta on the growth of MDA 231- and A375SM-derived pulmonary metastases in vivo and on survival. All statistical tests were two-sided. RESULTS: Co-culture of MSC-IFN-beta cells with A375SM cells or MDA 231 cells inhibited tumor cell growth as compared with growth of the tumor cells cultured alone (differences in mean percentage of control cell growth: -94.0% [95% confidence interval [CI] = -81.2% to -106.8%; P<.001] and -104.8% [95% CI = -82.1% to -127.5%; P<.001], respectively). Intravenous injection of MSC-IFN-beta cells into mice with established MDA 231 or A375SM pulmonary metastases led to incorporation of MSC in the tumor architecture and, compared with untreated control mice, to prolonged mouse survival (median survival for MDA 231-injected mice: 60 and 37 days for MSC-injected and control mice, respectively [difference = 23.0 days (95% CI = 14.5 to 34.0 days; P<.001]; median survival for A375SM-injected mice: 73.5 and 30.0 days for MSC-injected and control mice, respectively [difference = 43.5 days (95% CI = 37.0 to 57.5 days; P<.001]). By contrast, intravenous injection of recombinant IFN-beta did not prolong survival in the same models (median survival for MDA 231-injected mice: 41.0 and 37.0 days for IFN-beta-injected and control mice, respectively [difference = 4 days, 95% CI = -5 to 10 days; P = .308]; median survival for A375SM-injected mice: 32.0 and 30.0 days for IFN-beta-injected and control mice, respectively [difference = 2 days, 95% CI = 0 to 4.5 days; P = .059]). CONCLUSIONS: Injected MSC-IFN-beta cells suppressed the growth of pulmonary metastases, presumably through the local production of IFN-beta in the tumor microenvironment. MSC may be an effective platform for the targeted delivery of therapeutic proteins to cancer sites.

Bone marrow-derived mesenchymal stem cells as vehicles for interferon-beta delivery into tumors.

Molecules that physiologically control cell proliferation are often produced locally in tissues and are rapidly destroyed when they enter circulation. This allows local effects while avoiding interference with other systems. Unfortunately, it also limits the therapeutic use of these molecules via systemic delivery. We here demonstrate that, for the purpose of anticancer therapy, bone marrow-derived mesenchymal stem cells (MSCs) can produce biological agents locally at tumor sites. We show that the tumor microenvironment preferentially promotes the engraftment of MSCs as compared with other tissues. MSCs with forced expression of IFN-beta inhibited the growth of malignant cells in vivo. Importantly, this effect required the integration of MSCs into the tumors and could not be achieved by systemically delivered IFN-beta or by IFN-beta produced by MSCs at a site distant from the tumors. Our results indicate that MSCs may serve as a platform for delivery of biological agents in tumors.