Phase II trial of single-agent foretinib (GSK1363089) in patients with recurrent or metastatic squamous cell carcinoma of the head and neck

BACKGROUND

Foretinib is a small-molecule, oral multikinase inhibitor primarily targeting the mesenchymal epithelial transition (MET) factor receptor, and the vascular endothelial growth factor receptor 2. We conducted a phase II study to evaluate the single-agent activity and tolerability of foretinib in patients with recurrent/metastatic squamous cell carcinoma of the head and neck (SCCHN).

METHODS

An open-label, single-arm, multicenter trial employing a Simon 2-stage design was conducted with a total of 41 patients planned for the study. One or more responses in the first 14 patients were required in order to progress to the second stage. Foretinib was administered as 240 mg orally for 5 consecutive days of a 14-day treatment cycle (5/9 schedule) to patients with recurrent and/or metastatic SCCHN.

RESULTS

Fourteen patients were enrolled. The study did not meet criteria for continuing to the second stage. A maximum of 30 cycles were administered (median = 4.0). Fifty percent of patients (7/14) showed stable disease (SD), 43% of patients (6/14) experienced tumor shrinkage and two patients had prolonged disease stabilization for ≥13 months. The most common adverse events were fatigue, constipation and hypertension, which were manageable with additional medication or adjustments to the dosing schedule.

CONCLUSION

Foretinib 240 mg on a 5/9 schedule was generally well tolerated. SD was the best-observed outcome, with minor tumor shrinkage detected in nearly half of all patients. The efficacy results, prolonged disease stabilization and tolerable side-effect profile, support further investigation, possibly in combination with other targeted agents or cytotoxic chemotherapy for SCCHN.

Systemic treatment and medical management of metastatic squamous cell carcinoma of the head and neck: review of the literature and proposal for management changes

OBJECTIVE

Worldwide, head and neck carcinomas account for 5% of all malignancies. Two-thirds of patients relapse after initial multimodal therapy. Until early 2000, the median overall survival (OS) of metastatic patients was about 6 months. Recently, new drugs have been incorporated in patient management, thus enabling an increase in OS. This review aims to define the comprehensive medical management of patients with relapsing head and neck carcinoma.

METHODS

A comprehensive review of the literature was made targeting four topics: first- and second-line treatment, supportive care, and management of elderly patients.

RESULTS

The choice of first- or second-line treatments is mainly based on performance status. In the elderly, geriatric assessment could be helpful. For PS 0.1 patients, the standard first-line treatment is 6 cycles of cisplatin-5FU-cetuximab. In the event of response, cetuximab alone is prolonged until progression or unacceptable toxicity. For second-line treatment, several options are currently available: enrolment in clinical trials, single-agent therapy (methotrexate, taxane, cetuximab), and best supportive care (BSC). Supportive care has to be initiated very early in the course of the disease to prevent pain, dysphagia and malnutrition. In elderly patients, the therapeutic options are: first-line treatment with the EXTREME regimen replacing cisplatin by carboplatin for patients in good general condition or methotrexate alone for other patients. BSC continues to be given to all patients (i.e. poor general conditions).

CONCLUSION

In spite of numerous pending issues requiring further investigation, these recommendations seem to be routinely applicable.

Molecular-targeted therapies in head and neck cancer

The increasing understanding of tumor biology has opened the door to a new class of biological agents directed at specific molecular targets in the treatment of squamous cell carcinomas of the head and neck. These targeted agents present the opportunity to more effectively attack the crucial cellular pathways contributing to tumor growth and survival, while minimizing toxicity. Cetuximab, which targets epidermal growth factor (EGF) receptor signaling, was the first such biological agent to be proven effective in head and neck squamous cell cancers. Currently, there are dozens of targeted agents at various stages of testing for use in the treatment of head and neck cancers. In this article, we review strategies aimed at key pathways, including EGF receptor signaling, the Vascular Endothelial Growth Factor (VEGF) pathway, and PI3K/AKT/mammalian target of rapamycin activation.

Current treatment options for metastatic head and neck cancer

Head and neck squamous cell carcinoma is now the 8th most common cancer affecting men in the United States largely due to a rising epidemic of oropharynx cancer (tonsil and tongue base) associated with the human papillomavirus (HPV). The median overall survival for recurrent or metastatic head and neck cancer (R/M HNSCC) remains less than 1 year despite modern chemotherapy and targeted agents. Palliative chemotherapy and the epidermal growth factor receptor inhibitor, cetuximab, constitute the backbone of treatment for patients with R/M HNSCC. Platinum doublets studied in phase III trials include cisplatin/5-FU, cisplatin/paclitaxel, and cisplatin/pemetrexed. Platinum chemotherapy in combination with 5-fluorouracil and cetuximab has resulted in the longest median overall survival. Combination platinum regimens increase response rates and toxicity but not survival and should be reserved for patients who are symptomatic from their disease for whom the benefit of a partial response may be worth the cost of increased treatment-related side effects. For many patients who are asymptomatic with a low disease burden, single agent regimens are appropriate to balance treatment with side effects. Drugs commonly used as single agents in the treatment of R/M HNSCC include docetaxel, paclitaxel, cetuximab, capecitabine, pemetrexed, and methotrexate. Best supportive care alone is often appropriate for poor performance status patients. Palliative radiation therapy is beneficial for treating symptomatic metastatic sites. Aggressive symptom management is imperative for all patients and often should include referral to experts in palliative care and pain management. New therapies currently under investigation include mTOR inhibitors, anti-angiogenic agents, and IGF1R inhibitors. Given the poor prognosis for most patients with R/M HNSCC, enrollment in clinical trials investigating novel approaches to therapy should be encouraged.

A multiplicity of anti-invasive effects of farnesyl transferase inhibitor SCH66336 in human head and neck cancer

Metastasis is a critical event in the progression of head and neck squamous cell carcinoma (HNSCC) and closely correlates with clinical outcome. We previously showed that the farnesyl transferase inhibitor SCH66336 has antitumor activities in HNSCC by inducing the secretion of insulin-like growth factor binding protein 3 (IGFBP-3), which in turn inhibits tumor growth and angiogenesis. In our study, we found that SCH66336 at a sublethal dose for HNSCC inhibited the migration and invasion of HNSCC cells. The inhibitory effect of SCH66336 was associated with the blockade of the IGF-1 receptor (IGF-1R) pathway via suppressing IGF-1R itself and Akt expression. Consistent with previous work, induction of IGFBP-3 by SCH66336 also contributed in part to the anti-invasive effect. SCH66336 treatment also reduced the expression and activity of the urokinase-type plasminogen activator (uPA) and matrix metalloproteinase 2 (MMP-2), both important regulators of tumor metastasis. The effect of SCH66336 on uPA activity was inhibited partly by knockdown of IGFBP-3 using small interfering RNA. The inhibitory effect of SCH66336 on migration or invasion was attenuated partly or completely by knockdown of IGFBP-3, Akt or IGF-1R expression, respectively. Our results demonstrate that the IGF-1R pathway plays a major role in the proliferation, migration and invasion of HNSCC cells, suggesting that therapeutic obstruction of the IGF-1R pathway would be a useful approach to treating patients with HNSCC.

The role of the insulin-like growth factor signaling pathway in non-small cell lung cancer and other solid tumors

The type 1 insulin-like growth factor receptor (IGF-1R) and its downstream signaling components have become increasingly recognized as having a driving role in the development of malignancy, and consequently IGF-1R has become a potential target for cancer therapy. Several inhibitors of IGF-1R are in clinical development for the treatment of solid tumors, including non-small cell lung cancer (NSCLC). These IGF-1R-targeted agents include monoclonal antibodies such as cixutumumab (IMC-A12), AMG-479, AVE1642, BIIB022, dalotuzumab (MK-0646), and robatumumab (Sch717454), the ligand neutralizing antibody Medi-573, and the small molecule inhibitors BMS-754807, linsitinib (OSI-906), XL228, and AXL1717. Two phase III trials of the anti-IGF-1R monoclonal antibody, figitumumab (CP-751,871), were discontinued in 2010 as it was considered unlikely either trial would meet their primary endpoints. In light of disappointing clinical data with figitumumab and other targeted agents, it is likely that the use of molecular markers will become important in predicting response to treatment. This review outlines the role of IGF-1R signaling in solid tumors with a particular focus on NSCLC, and provides an overview of clinical data.