David A. Ramies

TRIBUTE: A Phase III Trial of Erlotinib Hydrochloride (OSI-774) Combined With Carboplatin and Paclitaxel Chemotherapy in Advanced Non–Small-Cell Lung Cancer

PURPOSE Erlotinib is a potent reversible HER1/epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor with single-agent activity in patients with non-small-cell lung cancer (NSCLC). Erlotinib was combined with chemotherapy to determine if it could improve the outcome of patients with NSCLC. PATIENTS AND METHODS TRIBUTE randomly assigned patients with good performance status and previously untreated advanced (stage IIIB/IV) NSCLC to erlotinib 150 mg/d or placebo combined with up to six cycles of carboplatin and paclitaxel, followed by maintenance monotherapy with erlotinib. Random assignment was stratified by stage, weight loss in the previous 6 months, measurable disease, and treatment center. The primary end point was overall survival (OS). Secondary end points included time to progression (TTP), objective response (OR), and duration of response. RESULTS There were 1,059 assessable patients (526 erlotinib; 533 placebo). Median survival for patients treated with erlotinib was 10.6 v 10.5 months for placebo (hazard ratio, 0.99; 95% CI, 0.86 to 1.16; P = .95). There was no difference in OR or median TTP. Patients who reported never smoking (72 erlotinib; 44 placebo) experienced improved OS in the erlotinib arm (22.5 v 10.1 months for placebo), though no other prespecified factors showed an advantage in OS with erlotinib. Erlotinib and placebo arms were equivalent in adverse events (except rash and diarrhea). CONCLUSION Erlotinib with concurrent carboplatin and paclitaxel did not confer a survival advantage over carboplatin and paclitaxel alone in patients with previously untreated advanced NSCLC. Never smokers treated with erlotinib and chemotherapy seemed to experience an improvement in survival and will undergo further investigation in future randomized trials.

Mutations in the Epidermal Growth Factor Receptor and in KRAS Are Predictive and Prognostic Indicators in Patients With Non–Small-Cell Lung Cancer Treated With Chemotherapy Alone and in Combination With Erlotinib

PURPOSE Epidermal growth factor receptor (EGFR) mutations have been associated with tumor response to treatment with single-agent EGFR inhibitors in patients with relapsed non-small-cell lung cancer (NSCLC). The implications of EGFR mutations in patients treated with EGFR inhibitors plus first-line chemotherapy are unknown. KRAS is frequently activated in NSCLC. The relationship of KRAS mutations to outcome after EGFR inhibitor treatment has not been described. PATIENTS AND METHODS Previously untreated patients with advanced NSCLC in the phase III TRIBUTE study who were randomly assigned to carboplatin and paclitaxel with erlotinib or placebo were assessed for survival, response, and time to progression (TTP). EGFR exons 18 through 21 and KRAS exon 2 were sequenced in tumors from 274 patients. Outcomes were correlated with EGFR and KRAS mutations in retrospective subset analyses. RESULTS EGFR mutations were detected in 13% of tumors and were associated with longer survival, irrespective of treatment (P < .001). Among erlotinib-treated patients, EGFR mutations were associated with improved response rate (P < .05) and there was a trend toward an erlotinib benefit on TTP (P = .092), but not improved survival (P = .96). KRAS mutations (21% of tumors) were associated with significantly decreased TTP and survival in erlotinib plus chemotherapy-treated patients. CONCLUSION EGFR mutations may be a positive prognostic factor for survival in advanced NSCLC patients treated with chemotherapy with or without erlotinib, and may predict greater likelihood of response. Patients with KRAS-mutant NSCLC showed poorer clinical outcomes when treated with erlotinib and chemotherapy. Further studies are needed to confirm the findings of this retrospective subset analysis.

Phase I/II trial evaluating the anti-vascular endothelial growth factor monoclonal antibody bevacizumab in combination with the HER-1/epidermal growth factor receptor tyrosine kinase inhibitor erlotinib for patients with recurrent non-small-cell lung cancer.

PURPOSE Bevacizumab (Avastin; Genentech, South San Francisco, CA) is a recombinant, humanized anti-vascular endothelial growth factor monoclonal antibody. Erlotinib HCl (Tarceva, OSI-774; OSI Pharmaceuticals, New York, NY) is a potent, reversible, highly selective and orally available HER-1/epidermal growth factor receptor tyrosine kinase inhibitor. Preclinical data in various xenograft models produced greater growth inhibition than with either agent alone. Additionally, both agents have demonstrated benefit in patients with previously treated non-small-cell lung cancer (NSCLC). PATIENTS AND METHODS A phase I/II study in two centers examined erlotinib and bevacizumab (A+T) in patients with nonsquamous stage IIIB/IV NSCLC with > or = one prior chemotherapy. In phase I, erlotinib 150 mg/day orally plus bevacizumab 15 mg/kg intravenously every 21 days was established as the phase II dose, although no dose-limiting toxicities were observed. Phase II assessed the efficacy and tolerability of A+T at this dose. Pharmacokinetic parameters were evaluated. ResultsForty patients were enrolled and treated in this study (34 patients at phase II dose); the median age was 59 years (range, 36 to 72 years), 21 were female, 30 had adenocarcinoma histology, nine were never-smokers, and 22 had > or = two prior regimens (three patients had > or = four prior regimens). The most common adverse events were mild to moderate rash, diarrhea, and proteinuria. Preliminary data showed no pharmacokinetic interaction between A + T. Eight patients (20.0%; 95% CI, 7.6% to 32.4%) had partial responses and 26 (65.0%; 95% CI, 50.2% to 79.8%) had stable disease as their best response. The median overall survival for the 34 patients treated at the phase II dose was 12.6 months, with progression-free survival of 6.2 months. CONCLUSION Encouraging antitumor activity and safety of A + T support further development of this combination for patients with advanced NSCLC and other solid tumors.

Phase II Study of Efficacy and Safety of Bevacizumab in Combination With Chemotherapy or Erlotinib Compared With Chemotherapy Alone for Treatment of Recurrent or Refractory Non–Small-Cell Lung Cancer

PURPOSE Bevacizumab, a humanized anti-vascular endothelial growth factor monoclonal antibody, and erlotinib, a reversible, orally available epidermal growth factor receptor tyrosine kinase inhibitor, have demonstrated evidence of a survival benefit in the treatment of non-small-cell lung cancer (NSCLC). A single-arm phase I and II study of bevacizumab plus erlotinib demonstrated encouraging efficacy, with a favorable safety profile. PATIENTS AND METHODS A multicenter, randomized phase II trial evaluated the safety of combining bevacizumab with either chemotherapy (docetaxel or pemetrexed) or erlotinib and preliminarily assessed these combinations versus chemotherapy alone, as measured by progression-free survival (PFS). All patients had histologically confirmed nonsquamous NSCLC that had progressed during or after one platinum-based regimen. RESULTS One hundred twenty patients were randomly assigned and treated. No unexpected adverse events were noted. Fewer patients (13%) in the bevacizumab-erlotinib arm discontinued treatment as a result of adverse events than in the chemotherapy alone (24%) or bevacizumab-chemotherapy (28%) arms. The incidence of grade 5 hemorrhage in patients receiving bevacizumab was 5.1%. Although not statistically significant, relative to chemotherapy alone, the risk of disease progression or death was 0.66 (95% CI, 0.38 to 1.16) among patients treated with bevacizumab-chemotherapy and 0.72 (95% CI, 0.42 to 1.23) among patients treated with bevacizumab-erlotinib. One-year survival rate was 57.4% for bevacizumab-erlotinib and 53.8% for bevacizumab-chemotherapy compared with 33.1% for chemotherapy alone. CONCLUSION Results for PFS and overall survival favor combination of bevacizumab with either chemotherapy or erlotinib over chemotherapy alone in the second-line setting. No unexpected safety signals were noted. The rate of fatal pulmonary hemorrhage was consistent with previous bevacizumab trials. The toxicity profile of the bevacizumab-erlotinib combination is favorable compared with either chemotherapy-containing group.

Activity of cabozantinib (XL184) in patients (pts) with metastatic, refractory renal cell carcinoma (RCC).

364 Background: Cabozantinib (cabo) is an oral, potent inhibitor of MET and VEGFR2 that is currently undergoing clinical efficacy evaluation in several oncology indications. Renal cell carcinoma (RCC) was chosen as an indication in this drug-drug interaction (DDI) study based on involvement of the MET and VEGFR signaling pathways in this disease. The primary objective of this study is to determine the effect of cabo on single dose PK of the CYP2C8 substrate rosiglitazone (rosi). The exploratory objective of this study is to evaluate the preliminary antitumor activity of cabo in pts with RCC. METHODS Eligible pts were required to have RCC with clear cell components with metastases, Karnofsky performance status of ≥70 and measurable disease by RECIST. Pts needed to have experienced PD following standard therapies. Method for DDI study: Day 1, 4 mg rosi; Days 2 - 22, cabo given daily at a dose of 175 mg; Day 22, 4 mg rosi to complete PK assessment for DDI. Cabo continued until PD. On Day 57 and every 8 weeks thereafter subjects underwent tumor assessments by mRECIST. RESULTS Enrollment is complete at 25 RCC pts with a median of 2 prior regimens; 17/25 (68%) RCC pts had received ≥ 2 lines of prior therapy and 13/25 (52%) with at least 1 VEGF pathway inhibitor and 1 mTOR inhibitor. All pts were intermediate (24/25) or poor (1/25) risk category per Heng et al prognostic strata (JCO 2009). Related AEs ≥ Grade 3 severity: hypophosphatemia 8 (32%), PE 3 (12%; all were incidental / resolved) and diarrhea 3 (12%). Preliminary PK data suggest that clinically relevant doses of cabo do not markedly alter the Cmax or AUC0-24h of rosi consistent with lack of inhibition of CYP2C8. RCC pts with confirmed PR by mRECIST: 6/25 (24%). Additionally, 1 pt had an unconfirmed PR. Disease control rate (PR + SD): 68% at 16 weeks; 18/21 (86%) pts with ≥1 post-baseline scan experienced tumor regression (range: 4 - 63% reduction in measurements). 14/25 (56%) remain on cabo with a median follow-up of 4 months. Median PFS and OS have not been reached. CONCLUSIONS Cabo demonstrates encouraging anti-tumor activity in heavily pretreated pts with RCC with a toxicity profile similar to that of other TKIs. Preliminary data suggest no DDI between cabo and rosi (CYP2C8 substrate).

Results of a Phase 2 Placebo-Controlled Randomized Discontinuation Trial of Cabozantinib in Patients with Non–Small-Cell Lung Carcinoma

Introduction: Cabozantinib, an orally bioavailable tyrosine kinase inhibitor with activity against MET, vascular endothelial growth factor receptor 2, AXL, ROS1, and RET was assessed in patients with non–small‐cell lung carcinoma (NSCLC) as part of a phase II randomized discontinuation trial with cohorts from 9 tumor types. Patients and Methods: Patients received cabozantinib 100 mg/day during a 12‐week open‐label lead‐in stage. Those with stable disease per Response Evaluation Criteria in Solid Tumors version 1.0 at week 12 were randomized to cabozantinib or placebo. Primary endpoints were objective response rate (ORR) at week 12 and progression‐free survival (PFS) after randomization. Results: Sixty patients with NSCLC who had received a median of 2 prior lines of therapy were enrolled. ORR at week 12 was 10%; 6 patients had a confirmed partial response, and no patients had a complete response. Overall disease‐control rate (ORR + stable disease) at week 12 was 38%. Tumor regression was observed in 30 (64%) of 47 patients with post‐baseline radiographic tumor assessments, including 3 or 4 patients with KRAS or epidermal growth factor receptor mutations, respectively. Median PFS after randomization was 2.4 months for both the cabozantinib and placebo arms. Median PFS from first dose for the entire cohort was 4.2 months. The most common grade 3/4 adverse events were fatigue (13%), palmar‐plantar erythrodysesthesia (10%), diarrhea (7%), hypertension (7%), and asthenia (5%); 1 treatment‐related grade 5 adverse event (hemorrhage) was reported during the lead‐in stage. Conclusion: Cabozantinib exhibited clinical activity based on ORR and regression of tumor lesions in pretreated patients with NSCLC, including in patients with KRAS mutations. Micro‐Abstract: Cabozantinib is an inhibitor of receptor tyrosine kinases, including MET, vascular endothelial growth factor receptors, AXL, RET, and ROS1. We assessed cabozantinib in 60 patients with non–small‐cell lung carcinoma enrolled in a phase II randomized discontinuation trial. Tumor regression was observed in most patients, including patients with KRAS and epidermal growth factor receptor mutations. The safety profile was consistent with that reported for cabozantinib in other solid tumors.