Developments in the treatment of early NSCLC: when to use chemotherapy

approximately 30% of lung carcinomas are resected and these cases are candidates for adjuvant treatments. The PORT meta-analysis reported in 1999 that postoperative radiotherapy had a detrimental effect for pathological N0 and N1 patients, and a debatable effect for N2 patients. Following the results of the 1995 meta-analysis on the role of chemotherapy (CT) in non-small-cell lung cancer (NSCLC), many randomized, controlled trials were launched to evaluate the effect of adjuvant cisplatin-based CT after the complete resection of NSCLC. The Lung adjuvant Ciplatin Evaluation pooled analysis included a total of 4584 patients recruited in five recent cisplatin-based adjuvant trials. It confirmed that adjuvant CT was associated with an absolute 5-year survival benefit of 5.3% (P = 0.0043). In addition, it showed that adjuvant cisplatin-based CT is detrimental in cases of stage Ia resected NSCLC; it also suggested that the combination of vinorelbine and cisplatin was of more benefit than older two and three drug combinations. The individual data-based meta-analysis was also updated with a total of over 10 000 patients. It confirmed the substantial effect of postoperative CT, with or without postoperative radiotherapy, with a substantial overall benefit of 4% at 5 years. Recent results of biological programs suggest that evaluating the expression of various tumor markers, including excision repair cross-complementation group 1, may allow the identification of patients most likely to benefit from CT. If these results are confirmed, tailored therapy might be the next step forward for resected NSCLC.

New oral multitargeted antiangiogenics in non-small-cell lung cancer treatment

Non-small-cell lung cancer is a particularly aggressive cancer. Combination chemotherapy remains the standard therapy for patients with advanced or metastatic disease. However, despite the available treatment options for patients who progress beyond first-line therapy, prognosis remains poor. Angiogenesis is a tightly regulated process controlled by a delicate balance between pro- and antiangiogenic factors and their receptors; tumors induce angiogenesis by disrupting this balance and secreting various growth factors. Inhibition of tumor-related angiogenesis has become an attractive target for anticancer therapy. Antiangiogenic strategy includes monoclonal antibodies against VEGF and VEGF receptor and small molecule inhibitors of VEGF tyrosine kinase activity (tyrosine kinase inhibitors). Tyrosine kinase inhibitors are orally active, small molecules that represent a new class of drugs with a relatively high safety profile. They are targeted therapies that play their anticancer role interfering with specific cell signaling. This review focuses on such oral antiangiogenic agents that have been approved and are in advanced clinical development for the treatment of patients with advanced non-small-cell lung cancer.

Targeted therapies for non-small cell lung cancer: an evolving landscape

Over the past decade, a multitude of targeted agents have been explored in the treatment of advanced non-small cell lung cancer (NSCLC). Thus far, two broad classes of agents have been implemented in clinical practice: (a) vascular endothelial growth factor (VEGF)-directed therapies and (b) antagonists of the epidermal growth factor receptor (EGFR). In the former category, the agent bevacizumab (a monoclonal antibody) has shown landmark improvements in survival when added to cytotoxic therapy. Small molecule tyrosine kinase inhibitors (TKI) targeting the VEGF receptor (i.e., sunitinib, sorafenib, and vandetanib) show activity in phase II clinical studies. With respect to EGFR-directed therapies, the TKIs gefitinib and erlotinib have shown significant benefit, and have uncovered valuable information about the biology of lung cancer. Outside of therapies directed specifically at VEGF- and EGFR-mediated signaling, trials evaluating insulin-like growth factor-1 receptor (IGF-IR)-targeting agents, cyclooxygenase-2 (COX-2) inhibitors, c-met inhibitors, irreversible pan-HER inhibitors, mammalian target of rapamycin (mTOR) inhibitors, and histone deacetylase (HDAC) inhibitors are ongoing. Inhibitors of ALK show great promise in patients with the relevant gene translocation. Herein, the clinical development of novel therapies for NSCLC is described, including some discussion of relevant biomarkers and determination of synergy with both cytotoxic therapy and other targeted agents.

Plasma cytokine and angiogenic factor profiling identifies markers associated with tumor shrinkage in early-stage non-small cell lung cancer patients treated with pazopanib

There is an unmet need for pharmacodynamic and predictive biomarkers for antiangiogenic agents. Recent studies have shown that soluble vascular endothelial growth factor receptor 2 (sVEGFR2), VEGF, and several other soluble factors may be modulated by VEGF pathway inhibitors. We conducted a broad profiling of cytokine and angiogenic factors (CAF) to investigate the relationship between baseline CAF levels, CAF changes during treatment, and tumor shrinkage in early-stage non-small cell lung cancer (NSCLC) patients treated with pazopanib, an oral angiogenesis inhibitor targeting VEGFR, platelet-derived growth factor receptor, and c-kit. Plasma samples were collected before treatment and on the last day of therapy from 33 patients with early-stage NSCLC participating in a single-arm phase II trial. Levels of 31 CAFs were measured by suspension bead multiplex assays or ELISA and correlated with change in tumor volume. Pazopanib therapy was associated with significant changes of eight CAFs; sVEGFR2 showed the largest decrease, whereas placental growth factor underwent the largest increase. Increases were also observed in stromal cell-derived factor-1alpha, IP-10, cutaneous T-cell-attracting chemokine, monokine induced by IFN-gamma, tumor necrosis factor-related apoptosis-inducing ligand, and IFN-alpha. Posttreatment changes in plasma sVEGFR2 and interleukin (IL)-4 significantly correlated with tumor shrinkage. Baseline levels of 11 CAFs significantly correlated with tumor shrinkage, with IL-12 showing the strongest association. Using multivariate classification, a baseline CAF signature consisting of hepatocyte growth factor and IL-12 was associated with tumor response to pazopanib and identified responding patients with 81% accuracy. These data suggest that CAF profiling may be useful for identifying patients likely to benefit from pazopanib, and merit further investigation in clinical trials.

Pazopanib: an antiangiogenic drug in perspective

Pazopanib, a tyrosine kinase inhibitor targeted to angiogenesis, has been tested in preclinical and clinical trials and has shown promising activity against a variety of solid tumors, such as renal cancer, all of which are related to the angiogenic pathway. It has a safety profile related to this mechanism of action. Diarrhea, hypertension, hair depigmentation and nausea are the most common side effects. Pazopanib is currently under evaluation as monotherapy and in combination with some potentially synergistic agents of proven activity.

[Towards a histologically guided management for NSCLC]

Currently the management of non-small cell lung cancer with first line chemotherapy is dependent on the histology. The growth of morbid anatomy laboratories and molecular biology, alongside the rapid expansion of new therapies, is necessary for the selection of patients according to predictive criteria of efficacy and tolerance, allowing definition of a made to measure treatment.

Immunotherapy in the landscape of new targeted treatments for non-small cell lung cancer

Non-small cell lung cancer (NSCLC) is the leading cause of cancer-related death worldwide. Active immunotherapies and molecules targeting tyrosine kinase receptors both offer new avenues for the treatment of NSCLC. Furthermore, their combinations or their administration along with standard treatments enlarges the potential for clinical benefit. Moreover, the discovery of biomarkers predicting the response to these new therapies should allow a better selection of patients susceptible to optimally benefit from these treatments. In this paper, we review the most promising active immunotherapies, antibodies and small molecules in the context of NSCLC management, focusing on compounds in phase III clinical development.

Angiogenesis inhibitors in the treatment of non-small cell lung cancer

A therapeutic plateau seems to have been reached with the standard treatment of cytotoxic chemotherapy alone for advanced stage non-small cell lung cancer (NSCLC) and new treatment options are urgently needed. Recent insight into the molecular biology of cancer has identified angiogenesis as one of the key biological processes. The major player in tumor angiogenesis is the vascular endothelial growth factor (VEGF) pathway. VEGF is expressed in the majority of NSCLC and overexpression is associated with a poor prognosis. The VEGF pathway can be inhibited in two main ways: targeting VEGF directly or inhibiting the VEGF receptors. The development of angiogenesis inhibitors has shown great promise in the treatment of NSCLC. Bevacizumab, an anti-VEGF antibody, has been approved for the treatment of advanced NSCLC and other drugs are undergoing phase III investigation. However, a number of unresolved issues remain. In this review, we discuss the main angiogenesis inhibitors in development for the treatment of NSCLC focusing on the VEGF pathway.

Phase I trial of pazopanib in patients with advanced cancer

PURPOSE

The safety, pharmacokinetics, and clinical activity of pazopanib (GW786034), an oral angiogenesis inhibitor targeting vascular endothelial growth factor receptor, platelet-derived growth factor receptor, and c-Kit, were evaluated in patients with advanced-stage refractory solid tumors.

EXPERIMENTAL DESIGN

Patients were enrolled into sequential dose-escalating cohorts (50 mg three times weekly to 2,000 mg once daily and 300-400 mg twice daily). Escalation or deescalation was based on toxicities observed in the preceding dose cohort. Pharmacokinetic and biomarker samples were obtained. Clinical response was assessed every 9 weeks.

RESULTS

Sixty-three patients were treated (dose escalation, n = 43; dose expansion, n = 20). Hypertension, diarrhea, hair depigmentation, and nausea were the most frequent drug-related adverse events, the majority of which were of grade 1/2. Hypertension was the most frequent grade 3 adverse event. Four patients experienced dose-limiting toxicities at 50 mg, 800 mg, and 2,000 mg once daily. A plateau in steady-state exposure was observed at doses of >or=800 mg once daily. The mean elimination half-life at this dose was 31.1 hours. A mean target trough concentration (C(24)) >or=15 microg/mL (34 micromol/L) was achieved at 800 mg once daily. Three patients had partial responses (two confirmed, one unconfirmed), and stable disease of >or=6 months was observed in 14 patients; clinical benefit was generally observed in patients who received doses of >or=800 mg once daily or 300 mg twice daily.

CONCLUSION

Pazopanib was generally well tolerated and showed antitumor activity across various tumor types. A monotherapy dose of 800 mg once daily was selected for phase II studies.