Bioequivalence and Relative Bioavailability Studies to Assess a New Acalabrutinib Formulation That Enables Coadministration With Proton-Pump Inhibitors.

Acalabrutinib is a Bruton tyrosine kinase (BTK) inhibitor approved to treat adults with chronic lymphocytic leukemia, small lymphocytic lymphoma, or previously treated mantle cell lymphoma. As the bioavailability of the acalabrutinib capsule (AC) depends on gastric pH for solubility and is impaired by acid-suppressing therapies, coadministration with proton-pump inhibitors (PPIs) is not recommended. Three studies in healthy subjects (N = 30, N = 66, N = 20) evaluated the pharmacokinetics (PKs), pharmacodynamics (PDs), safety, and tolerability of acalabrutinib maleate tablet (AT) formulated with pH-independent release. Subjects were administered AT or AC (orally, fasted state), AT in a fed state, or AT in the presence of a PPI, and AT or AC via nasogastric (NG) route. Acalabrutinib exposures (geometric mean [% coefficient of variation, CV]) were comparable for AT versus AC (AUCinf 567.8 ng h/mL [36.9] vs 572.2 ng h/mL [38.2], Cmax 537.2 ng/mL [42.6] vs 535.7 ng/mL [58.4], respectively); similar results were observed for acalabrutinib's active metabolite (ACP-5862) and for AT-NG versus AC-NG. The geometric mean Cmax for acalabrutinib was lower when AT was administered in the fed versus the fasted state (Cmax 255.6 ng/mL [%CV, 46.5] vs 504.9 ng/mL [49.9]); AUCs were similar. For AT + PPI, geometric mean Cmax was lower (371.9 ng/mL [%CV, 81.4] vs 504.9 ng/mL [49.9]) and AUCinf was higher (AUCinf 694.1 ng h/mL [39.7] vs 559.5 ng h/mL [34.6]) than AT alone. AT and AC were similar in BTK occupancy. Most adverse events were mild with no new safety concerns. Acalabrutinib formulations were comparable and AT could be coadministered with PPIs, food, or via NG tube without affecting the PKs or PDs.

Results of a Phase II 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.

Phase III Study of Cabozantinib in Previously Treated Metastatic Castration-Resistant Prostate Cancer: COMET-1.

PURPOSE: Cabozantinib is an inhibitor of kinases, including MET and vascular endothelial growth factor receptors, and has shown activity in men with previously treated metastatic castration-resistant prostate cancer (mCRPC). This blinded phase III trial compared cabozantinib with prednisone in patients with mCRPC. PATIENTS AND METHODS: Men with progressive mCRPC after docetaxel and abiraterone and/or enzalutamide were randomly assigned at a two-to-one ratio to cabozantinib 60 mg once per day or prednisone 5 mg twice per day. The primary end point was overall survival (OS). Bone scan response (BSR) at week 12 as assessed by independent review committee was the secondary end point; radiographic progression-free survival (rPFS) and effects on circulating tumor cells (CTCs), bone biomarkers, serum prostate-specific antigen (PSA), and symptomatic skeletal events (SSEs) were exploratory assessments. RESULTS: A total of 1,028 patients were randomly assigned to cabozantinib (n = 682) or prednisone (n = 346). Median OS was 11.0 months with cabozantinib and 9.8 months with prednisone (hazard ratio, 0.90; 95% CI, 0.76 to 1.06; stratified log-rank P = .213). BSR at week 12 favored cabozantinib (42% v 3%; stratified Cochran-Mantel-Haenszel P < .001). rPFS was improved in the cabozantinib group (median, 5.6 v 2.8 months; hazard ratio, 0.48; 95% CI, 0.40 to 0.57; stratified log-rank P < .001). Cabozantinib was associated with improvements in CTC conversion, bone biomarkers, and post-random assignment incidence of SSEs but not PSA outcomes. Grade 3 to 4 adverse events and discontinuations because of adverse events were higher with cabozantinib than with prednisone (71% v 56% and 33% v 12%, respectively). CONCLUSION: Cabozantinib did not significantly improve OS compared with prednisone in heavily treated patients with mCRPC and progressive disease after docetaxel and abiraterone and/or enzalutamide. Cabozantinib had some activity in improving BSR, rPFS, SSEs, CTC conversions, and bone biomarkers but not PSA outcomes.

Effect of Renal and Hepatic Impairment on the Pharmacokinetics of Cabozantinib.

Cabozantinib is a tyrosine kinase inhibitor approved for the treatment of patients with progressive, metastatic medullary thyroid cancer. Two clinical pharmacology studies were conducted to characterize single-dose pharmacokinetics (PK) of cabozantinib in renally or hepatically impaired subjects. Study 1 enrolled 10 subjects, each with mild or moderate impairment of renal function; 12 healthy subjects were matched to the moderate group for age, sex, and body mass index (BMI). Study 2 enrolled 8 males each with mild or moderate hepatic impairment; 10 healthy males were matched to the moderate group for age, BMI, and ethnicity. All subjects received one 60 mg cabozantinib oral capsule dose followed by PK sampling over 21 days. Plasma concentration and protein binding were determined by liquid chromatography tandem mass spectrometry and equilibrium dialysis, respectively. PK parameters were computed using noncompartmental methods. Geometric least squared mean (LSM) ratios for plasma cabozantinib AUC0-∞ for impaired to normal organ function cohorts were (1) approximately 30% and 6% higher in subjects with mild and moderate renal impairment, respectively, and (2) approximately 81% and 63% higher in subjects with mild and moderate hepatic impairment, respectively. The percentage of unbound drug was slightly higher in both moderately impaired cohorts. No deaths or discontinuations due to adverse events occurred in either study. Cabozantinib should be used with caution in subjects with mild or moderate renal impairment. Subjects with mild or moderate hepatic impairment administered cabozantinib should be monitored closely for potential treatment-emergent drug toxicity that may necessitate a dose hold or reduction.

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.

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.

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.

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 I trial of irinotecan, infusional 5-fluorouracil, and leucovorin (FOLFIRI) with erlotinib (OSI-774): early termination due to increased toxicities.

PURPOSE: This phase I study was conducted to establish the dose-limiting toxicities and maximum-tolerated dose of erlotinib, an oral epidermal growth factor receptor tyrosine kinase inhibitor, in combination with FOLFIRI, a standard regimen of irinotecan, leucovorin, and infusional 5-fluorouracil (5-FU) in patients with advanced colorectal cancer. EXPERIMENTAL DESIGN: The trial used a dose-escalation design beginning with 100 mg/day erlotinib continuously and dose-reduced FOLFIRI (150 mg/m2 i.v. day 1 irinotecan, 200 mg/m2 i.v. leucovorin, 320 mg/m2 i.v. bolus days 1 to 2 5-FU, and 480 mg/m2 i.v. 5-FU infusion over 22 hours, days 1 to 2) administered in 6-week cycles (three FOLFIRI treatments). Plasma sampling was performed for irinotecan, erlotinib, and 5-FU for pharmacokinetic analysis during cycle 1. RESULTS: The study was halted after six patients at the lowest dose level due to unexpectedly severe toxicities, including disfiguring grade 2 rash (three patients), grade 3 diarrhea (three patients), and grade > or = 3 neutropenia (three patients). All patients required some dose interruption or reduction of either erlotinib or FOLFIRI, and only one patient completed two 6-week cycles of therapy. Five patients had stable disease after one cycle, and one patient had a partial response. No plasma pharmacokinetic interaction was observed that could explain the observed increased toxicity. CONCLUSIONS: FOLFIRI combined with erlotinib causes excessive toxicity at reduced doses. These findings contrast with available data regarding the optimal safety profile of trials combining small molecule epidermal growth factor receptor inhibitors with other conventional chemotherapy and highlight the need to perform safety-oriented studies of such combinations.