Mark Kozloff

Bevacizumab Beyond First Progression Is Associated With Prolonged Overall Survival in Metastatic Colorectal Cancer: Results From a Large Observational Cohort Study (BRiTE)

PURPOSE Bevacizumab provides a survival benefit in first- and second-line metastatic colorectal cancer (mCRC). In a large, observational, bevacizumab treatment study (Bevacizumab Regimens: Investigation of Treatment Effects and Safety [BRiTE]) in patients who had mCRC, a longer-than-expected overall survival (OS) of 25.1 months was reported. The association between various pre- and post-treatment factors (including the use of bevacizumab beyond first progression [BBP]) and survival was examined. PATIENTS AND METHODS The 1,445 of 1,953 previously untreated patients with mCRC who were enrolled in BRiTE and who experienced disease progression (PD) were classified into three groups: no post-PD treatment (n = 253), post-PD treatment without bevacizumab (no BBP; n = 531), and BBP (n = 642). Relevant baseline and on-study variables, including BBP, were analyzed with a Cox model with respect to their independent effect on survival beyond first PD. RESULTS Median OS was 25.1 months (95% CI, 23.4 to 27.5 months), and median progression-free survival was 10.0 months in the overall BRiTE population. Baseline and postbaseline factors were well balanced between the BBP and no-BBP groups. Median OS rates were 12.6, 19.9, and 31.8 months in the no post-PD treatment, no-BBP, and BBP groups, respectively. In multivariate analyses, compared with no BBP, BBP was strongly and independently associated with improved survival (HR, 0.48; P < .001). Hypertension that required medication was the only bevacizumab-related safety event that occurred more frequently in the BBP group (24.6% v 19.2%). CONCLUSION These results from a large, prospective, observational study suggest that continued vascular endothelial growth factor inhibition with bevacizumab beyond initial PD could play an important role improving the overall success of therapy for patients who have mCRC.

Erlotinib and bevacizumab in patients with recurrent or metastatic squamous-cell carcinoma of the head and neck: a phase I/II study

BACKGROUND Epidermal growth factor receptor (EGFR) is a validated target in squamous-cell carcinoma of the head and neck, but in patients with recurrent or metastatic disease, EGFR targeting agents have displayed modest efficacy. Vascular endothelial growth factor (VEGF)-mediated angiogenesis has been implicated as a mechanism of resistance to anti-EGFR therapy. In this multi-institutional phase I/II study we combined an EGFR inhibitor, erlotinib, with an anti-VEGF antibody, bevacizumab. METHODS Between April 15, 2003, and Jan 27, 2005, patients with recurrent or metastatic squamous-cell carcinoma of the head and neck were enrolled from seven centres in the USA and were given erlotinib (150 mg daily) and bevacizumab in escalating dose cohorts. The primary objectives in the phase I and II sections, respectively, were to establish the maximum tolerated dose and dose-limiting toxicity of bevacizumab when administered with erlotinib and to establish the proportion of objective responses and time to disease progression. Pretreatment serum and tissues were collected and analysed by enzyme-linked immunosorbent assay and immunofluorescence quantitative laser analysis, respectively. This study was registered with ClinicalTrials.gov, number NCT00055913. FINDINGS In the phase I section of the trial, ten patients were enrolled in three successive cohorts with no dose-limiting toxic effects noted. 46 patients were enrolled in the phase II section of the trial (including three patients from the phase I section) on the highest dose of bevacizumab (15 mg/kg every 3 weeks). Two additional patients were accrued beyond the protocol-stipulated 46, leaving a total of 48 patients for the phase II assessment. The most common toxic effects of any grade were rash and diarrhoea (41 and 16 of 48 patients, respectively). Three patients had serious bleeding events of grade 3 or higher. Seven patients had a response, with four showing a complete response allowing rejection of the null hypothesis. Median time of overall survival and progression-free survival (PFS) were 7.1 months (95% CI 5.7-9.0) and 4.1 months (2.8-4.4), respectively. Higher ratios of tumour-cell phosphorylated VEGF receptor-2 (pVEGFR2) over total VEGFR2 and endothelial-cell pEGFR over total EGFR in pretreatment biopsies were associated with complete response (0.704 vs 0.386, p=0.036 and 0.949 vs 0.332, p=0.036, respectively) and tumour shrinkage (p=0.007 and p=0.008, respectively) in a subset of 11 patients with available tissue. INTERPRETATION The combination of erlotinib and bevacizumab is well tolerated in recurrent or metastatic squamous-cell carcinoma of the head and neck. A few patients seem to derive a sustained benefit and complete responses were associated with expression of putative targets in pretreatment tumour tissue.

Phase I Study of G3139, a bcl-2 Antisense Oligonucleotide, Combined With Carboplatin and Etoposide in Patients With Small-Cell Lung Cancer

PURPOSE Bcl-2 is expressed in the majority of cases of small cell lung cancer (SCLC) and may contribute to chemotherapeutic resistance. Bcl-2 suppression by G3139 (oblimersen sodium), a phosphorothioate oligonucleotide complementary to the bcl-2 mRNA, has the potential to enhance the antitumor efficacy of standard cytotoxic chemotherapy. A dose-finding study was performed evaluating the combination of G3139, carboplatin, and etoposide in patients with previously untreated extensive stage SCLC. PATIENTS AND METHODS Sixteen patients were treated in three consecutive cohorts. Cohort 1 (n=5) received G3139 5 mg/kg/d on days 1 to 8 of a 21 day cycle, with carboplatin area under the curve (AUC)=6 on day 6, and etoposide 80 mg/m2/d on days 6 to 8. In cohort 2 (n=4), carboplatin dose was reduced to AUC=5. In cohort 3 (n=7), G3139 dose was escalated to 7 mg/kg/d. G3139 plasma concentrations and Bcl-2 protein levels in peripheral blood mononuclear cells were evaluated. RESULTS Two of three assessable patients in cohort 1 experienced cycle 1 dose-limiting toxicity (grade 4 neutropenia). No cycle 1 dose-limited toxicity was observed in cohorts 2 or 3. Of 14 patients assessable for response, partial response was documented in 12 patients (86%), and stable disease in two. Median time to progression was 5.9 months. Carboplatin and etoposide administration did not appear to alter G3139 pharmacokinetics. No evidence of Bcl-2 suppression in peripheral blood mononuclear cells was observed. CONCLUSION The combination of G3139, carboplatin, and etoposide is well tolerated and results in an encouraging response rate and time to progression in patients with extensive stage SCLC.

Ethnic Differences and Functional Analysis of MET Mutations in Lung Cancer

Purpose: African Americans have higher incidence and poorer response to lung cancer treatment compared with Caucasians. However, the underlying molecular mechanisms for the significant ethnic difference are not known. The present study examines the ethnic differences in the type and frequency of MET proto-oncogene (MET) mutation in lung cancer and correlated them with other frequently mutated genes such as epidermal growth factor receptor (EGFR), KRAS2, and TP53. Experimental Design: Using tumor tissue genomic DNA from 141 Asian, 76 Caucasian, and 66 African American lung cancer patients, exons coding for MET and EGFR were PCR amplified, and mutations were detected by sequencing. Mutation carriers were further screened for KRAS2 and TP53 mutations. Functional implications of important MET mutations were explored by molecular modeling and hepatocyte growth factor binding studies. Results: Unlike the frequently encountered somatic mutations in EGFR, MET mutations in lung tumors were germline. MET-N375S, the most frequent mutation of MET, occurred in 13% of East Asians compared with none in African Americans. The frequency of MET mutations was highest among male smokers and squamous cell carcinoma. The MET-N375S mutation seems to confer resistance to MET inhibition based on hepatocyte growth factor ligand binding, molecular modeling, and apoptotic susceptibility to MET inhibitor studies. Conclusions: MET in lung cancer tissues contained nonsynonymous mutations in the semaphorin and juxtamembrane domains but not in the tyrosine kinase domain. All the MET mutations were germline. East Asians, African-Americans, and Caucasians had different MET genotypes and haplotypes. MET mutations in the semaphorin domain affected ligand binding. (Clin Cancer Res 2009;15(18):5714–23)

Induction chemotherapy followed by concomitant chemoradiotherapy for advanced head and neck cancer: impact on the natural history of the disease.

PURPOSE To determine survival rates and the pattern of failure in head and neck cancer patients treated with induction chemotherapy, limited surgery and concomitant chemoradiotherapy. PATIENTS AND METHODS Three cycles of induction chemotherapy with cisplatin, fluorouracil (5-FU), leucovorin, and interferon alfa-2b (PFL-IFN) were followed by optional surgery, and seven or eight cycles of 5-FU, hydroxyurea, and concurrent radiation for 5 days (FHX) for a total radiation dose of 65 to 75 Gy. Surgical resection was performed with the intent to spare organ function. RESULTS Seventy-one patients were treated at three institutions. Sixty-five patients (91%) had stage IV disease with N2/3 in 46. Thirty-three patients (51%; 95% confidence interval, 39% to 63%) achieved a clinical complete response (CR) to PFL-IFN. Local therapy consisted of surgery in 37 and/or FHX in 55 patients. With a median follow-up duration of 37 months, there have been 20 recurrences (15 local, four distant, and one both local and distant), and 29 deaths, 15 in patients with disease progression and 14 not directly related to the primary tumor. Four patients have developed second malignancies. At 3 years, 69% (+/- 6%) are progression-free and the overall survival rate is 60% (+/- 6%). Toxicity of PFL-IFN included severe or life-threatening mucositis (54%) and myelosuppression (60%). Five patients died of toxicity. During FHX, 70% of patients had grade 3 or 4 mucositis. CONCLUSION PFL-IFN is highly active, producing clinical CRs in 51% of patients, and, when followed by FHX, resulting in high local and distant control and overall survival rates. Second malignancies and intercurrent medical disease emerge as major risks to long-term survival. In view of the high toxicity and long treatment duration, further modifications of this approach are required.

Clinical Outcomes in Elderly Patients with Metastatic Colorectal Cancer Receiving Bevacizumab and Chemotherapy: Results from the BRiTE Observational Cohort Study

Background: Elderly patients are underrepresented in clinical trials and frequently undertreated with standard therapy. The BRiTE observational cohort study assessed the safety and effectiveness of bevacizumab-based first-line therapy for metastatic colorectal cancer among a large cohort of elderly patients (896 patients ≧65 years, among 1,953 total patients). Methods: Treatment patterns, safety, progression-free survival (PFS), overall survival (OS) and survival beyond first progression (SBP) were analyzed by age cohorts. OS and SBP were further analyzed using Cox proportional hazards regression. Results: Median PFS (months) was similar across age cohorts (<65 years, 9.8; 65 to <75, 9.6; 75 to <80, 10.0; ≧80, 8.6). Median OS (months) decreased with age (<65 years, 26.0; 65 to <75, 21.1; 75 to <80, 20.3; ≧80, 16.2). SBP declined with age; however, a Cox model adjusting for baseline and postbaseline covariates that were imbalanced among age cohorts showed a reduced independent effect of age on SBP (months) (<65 years, 12.0; 65 to <75, 11.4; 75 to <80, 11.3; ≧80, 10.0) compared with unadjusted analyses. Use of bevacizumab in subsequent postprogression regimens decreased with age. Incidence of targeted adverse events did not increase with age, except for arterial thromboembolic events (ATEs), for which Eastern Cooperative Oncology Group performance status, anticoagulation and arterial disease history were stronger prognostic factors than age. Conclusions: Elderly patients receiving bevacizumab with first-line chemotherapy showed treatment benefit, although there was reduced median survival with increasing age. There was no increased toxicity among elderly patients, except for risk of ATEs.

Induction chemotherapy followed by concurrent chemoradiation for advanced head and neck cancer: improved disease control and survival.

PURPOSE To determine tumor response rate, patterns of failure, toxicity, and survival in advanced squamous head and neck cancer after a combined treatment program that consists of induction chemotherapy, organ-sparing surgery, and concurrent chemoradiation. Long-term outcome data are presented. PATIENTS AND METHODS Between July 1991 and March 1993, 93 patients received three cycles of induction chemotherapy that consisted of cisplatin, fluorouracil (5-FU), l-leucovorin, and alpha-interferon2b (PFLl-alpha) followed by optional limited surgery and six to eight cycles of 5-FU, hydroxyurea, and concurrent radiation (FHX) to a total radiation dose of 65 to 75 Gy. RESULTS Ninety-three patients were entered onto this study and 97% had stage IV disease, with 66 patients who were N2 or N3. Sixty-one patients (66%) achieved a clinical complete remission (CR) after induction therapy. Thirty-four patients underwent surgery. Seventy-nine patients proceeded to FHX. With a median follow-up time of 43 months for surviving patients, 20 patients have had disease progression (13 local, two distant, five both), and there have been 35 deaths (18 from disease, six treatment-related, two from a second primary, and nine for other medical reasons). At 5 years, progression-free survival is 68%, and overall survival is 62%. Surgery was organ-preserving, as only a single laryngectomy and no glossectomies were performed in primary management. Acute toxicity related to PFLl-alpha consisted of severe or life-threatening mucositis in 57% and leucopenia in 65% of patients. During FHX, 81% of patients had grade 3 or 4 mucositis. CONCLUSION PFLl-alpha is a highly active regimen that induced clinical CR in two thirds of patients. When followed by limited surgery and FHX, resultant local and distant disease control, organ preservation, and overall 5-year survival are very promising in high-risk stage IV patients. Based on these local control and survival data, further evaluation of this treatment sequence, induction chemotherapy followed by concurrent chemoradiation, is warranted. Identification of similarly active but less toxic regimens is a high priority.

Induction chemotherapy with cisplatin, fluorouracil, and high-dose leucovorin for locally advanced head and neck cancer: a clinical and pharmacologic analysis.

Both cisplatin and leucovorin (LV) interact with fluorouracil (5-FU) by increasing intracellular reduced folate levels and thereby the inhibition of thymidylate synthase. Therefore, the addition of LV to cisplatin and 5-FU (PFL) may increase the activity of that combination in head and neck cancer. We treated 31 patients with locally advanced head and neck cancer with two cycles of neoadjuvant PFL consisting of 100 mg/m2 of cisplatin on day 1 followed by a 5-day continuous infusion of 5-FU at 1,000 mg/m2/day and oral LV at 100 mg administered every 4 hours during the entire duration of chemotherapy infusion. Two patients died during neoadjuvant chemotherapy of sudden death and sepsis, respectively, and were not evaluated for response. Of 29 evaluable patients, nine had a complete response (CR), 17 had a partial response (PR), and three had stable disease. Toxicities consisted of mild to moderate myelosuppression and moderate to severe mucositis, necessitating reduction of 5-FU on cycle 2 to less than or equal to 80% of the intended dose in 22 of 29 patients. Administration of LV by repeated oral dosing resulted in total reduced folate plasma concentrations of 5.3 (+/- 2.9) and 6.7 (+/- 3.4) mumol on days 2 and 4 of the 5-FU infusion. The sum of 1-LV and its metabolite 5-CH3-tetrahydrofolate exceeded the concentration of d-LV, consistent with selective absorption of the biologically active 1-stereoisomer from the gastrointestinal tract.

Randomized Phase Ib/II Study of Gemcitabine Plus Placebo or Vismodegib, a Hedgehog Pathway Inhibitor, in Patients With Metastatic Pancreatic Cancer

Purpose Sonic hedgehog (SHH), an activating ligand of smoothened (SMO), is overexpressed in > 70% of pancreatic cancers (PCs). We investigated the impact of vismodegib, an SHH antagonist, plus gemcitabine (GV) or gemcitabine plus placebo (GP) in a multicenter phase Ib/randomized phase II trial and preclinical PC models. Patients and Methods Patients with PC not amenable to curative therapy who had received no prior therapy for metastatic disease and had Karnofsky performance score ≥ 80 were enrolled. Patients were randomly assigned in a one-to-one ratio to GV or GP. The primary end point was progression-free-survival (PFS). Exploratory correlative studies included serial SHH serum levels and contrast perfusion computed tomography imaging. To further investigate putative biologic mechanisms of SMO inhibition, two autochthonous pancreatic cancer models (KrasG12D; p16/p19fl/fl; Pdx1-Cre and KrasG12D; p53R270H/wt; Pdx1-Cre) were studied. Results No safety issues were identified in the phase Ib portion (n = 7), and the phase II study enrolled 106 evaluable patients (n = 53 in each arm). Median PFS was 4.0 and 2.5 months for GV and GP arms, respectively (95% CI, 2.5 to 5.3 and 1.9 to 3.8, respectively; adjusted hazard ratio, 0.81; 95% CI, 0.54 to 1.21; P = .30). Median overall survival (OS) was 6.9 and 6.1 months for GV and GP arms, respectively (95% CI, 5.8 to 8.0 and 5.0 to 8.0, respectively; adjusted hazard ratio, 1.04; 95% CI, 0.69 to 1.58; P = .84). Response rates were not significantly different. There were no significant associations between correlative markers and overall response rate, PFS, or OS. Preclinical trials revealed no significant differences with vismodegib in drug delivery, tumor growth rate, or OS in either model. Conclusion The addition of vismodegib to gemcitabine in an unselected cohort did not improve overall response rate, PFS, or OS in patients with metastatic PC. Our preclinical and clinical results revealed no statistically significant differences with respect to drug delivery or treatment efficacy using vismodegib.

A phase II study of lapatinib in recurrent/metastatic squamous cell carcinoma of the head and neck.

Purpose: This study sought to determine the efficacy and safety profile of lapatinib in patients with recurrent/metastatic squamous cell carcinoma of the head and neck (SCCHN). Experimental Design: This phase II multiinstitutional study enrolled patients with recurrent/metastatic SCCHN into two cohorts: those without (arm A) and those with (arm B) before exposure to an epidermal growth factor receptor (EGFR) inhibitor. All subjects were treated with lapatinib 1,500 mg daily. Primary endpoints were response rate (arm A) and progression-free survival (PFS; arm B). The biologic effects of lapatinib on tumor growth and survival pathways were assessed in paired tumor biopsies obtained before and after therapy. Results: Forty-five patients were enrolled, 27 in arm A and 18 in arm B. Diarrhea was the most frequent toxicity occurring in 49% of patients. Seven patients experienced related grade 3 toxicity (3 fatigue, 2 hyponatremia, 1 vomiting, and 1 diarrhea). In an intent-to-treat analysis, no complete or partial responses were observed, and stable disease was the best response observed in 41% of arm A (median duration, 50 days, range, 34–159) and 17% of arm B subjects (median, 163 days, range, 135–195). Median PFS was 52 days in both arms. Median OS was 288 (95% CI, 62–374) and 155 (95% CI, 75–242) days for arms A and B, respectively. Correlative analyses revealed an absence of EGFR inhibition in tumor tissue. Conclusion: Lapatinib as a single agent in recurrent/metastatic SCCHN, although well tolerated, appears to be inactive in either EGFR inhibitor naive or refractory subjects. Clin Cancer Res; 18(8); 2336–43. ©2012 AACR.