Patient-reported outcome measures in a pharmacokinetic study with sunitinib, a prospective cohort study.

PURPOSE: During treatment with tyrosine kinase inhibitors, such as sunitinib, patients experience treatment and/or disease-related symptoms. Although application of patient-reported outcome measures (PROMs) enhances early recognition of symptoms, early clinical trials are focused on symptom severity objectified by the Common Terminology Criteria for Adverse Events (CTCAE) in order to evaluate drug safety and to determine a personalized and/or safe dosage range. To gain insight into patient-reported symptoms in addition to healthcare professional-reported adverse events (AEs), a substudy was conducted in an ongoing pharmacokinetic-guided sunitinib dosing study. METHODS: In patients for whom sunitinib was considered standard therapy or patients with advanced/metastatic tumors for whom no standard therapy was available, patient-reported symptoms and well-being besides healthcare professional-reported AEs were assessed. RESULTS: Twenty-nine patients were included for analysis. Over 50% of them experienced a decreased well-being, caused by symptoms of mild and moderate intensity. Compared to healthcare professionals, all measured symptoms, with the exception of fatigue and vomiting, were reported statistically significantly more often by patients. CONCLUSIONS: Application of PROMs in early clinical trials on personalized or individualized oral targeted anticancer agents is feasible and enhances early recognition of symptom burden due to multiple CTCAE grade 1-2 AEs, just as pro-active symptom management and effect evaluation of interventions performed. Application of PROMs in these trials might be clinically relevant in obtaining dose-limiting toxicities.

Pharmacokinetically guided sunitinib dosing: a feasibility study in patients with advanced solid tumours.

BACKGROUND: Plasma exposure of sunitinib shows large inter-individual variation. Therefore, a pharmacokinetic (PK) study was performed to determine safety and feasibility of sunitinib dosing based on PK levels. METHODS: Patients were treated with sunitinib 37.5 mg once daily. At days 15 and 29 of treatment, plasma trough levels of sunitinib and N-desethyl sunitinib were measured. If the total trough level (TTL) was <50 ng ml(-1) and the patient did not show any grade ⩾3 toxicity, the daily sunitinib dose was increased by 12.5 mg. If the patient suffered from grade ⩾3 toxicity, the sunitinib dose was lowered by 12.5 mg. RESULTS: Twenty-nine out of 43 patients were evaluable for PK assessments. Grade ⩾3 adverse events were experienced in seven patients (24%) at the starting dose and in nine patients (31%) after dose escalation. TTLs were below target in 15 patients (52%) at the starting dose. Of these, five patients (17%) reached target TTL after dose escalation without additional toxicity. CONCLUSIONS: In a third of the patients that were below target TTL at standard dose, the sunitinib dose could be increased without additional toxicities. This could be the basis for future studies and the implementation of a PK-guided dosing strategy in clinical practice.

A randomized phase II study comparing erlotinib versus erlotinib with alternating chemotherapy in relapsed non-small-cell lung cancer patients: the NVALT-10 study.

BACKGROUND: Epidermal growth factor receptor tyrosine kinase inhibitors (TKIs) administered concurrently with chemotherapy did not improve outcome in non-small-cell lung cancer (NSCLC). However, in preclinical models and early phase noncomparative studies, pharmacodynamic separation of chemotherapy and TKIs did show a synergistic effect. PATIENTS AND METHODS: A randomized phase II study was carried out in patients with advanced NSCLC who had progressed on or following first-line chemotherapy. Erlotinib 150 mg daily (monotherapy) or erlotinib 150 mg during 15 days intercalated with four 21-day cycles docetaxel for squamous (SQ) or pemetrexed for nonsquamous (NSQ) patients was administered (combination therapy). After completion of chemotherapy, erlotinib was continued daily. Primary end point was progression-free survival (PFS). RESULTS: Two hundred and thirty-one patients were randomized, 115 in the monotherapy arm and 116 in the combination arm. The adjusted hazard ratio for PFS was 0.76 [95% confidence interval (CI) 0.58-1.02; P = 0.06], for overall survival (OS) 0.67 (95% CI 0.49-0.91; P = 0.01) favoring the combination arm. This improvement was primarily observed in NSQ subgroup. Common Toxicity Criteria grade 3+ toxic effect occurred in 20% versus 56%, rash in 7% versus 15% and febrile neutropenia in 0% versus 6% in monotherapy and combination therapy, respectively. CONCLUSIONS: PFS was not significantly different between the arms. OS was significantly improved in the combination arm, an effect restricted to NSQ histology. STUDY REGISTRATION NUMBER: NCT00835471.

Method development and validation for the quantification of dasatinib, erlotinib, gefitinib, imatinib, lapatinib, nilotinib, sorafenib and sunitinib in human plasma by liquid chromatography coupled with tandem mass spectrometry.

To support pharmacokinetic-guided dosing in individual patients, a fast and accurate method for simultaneous determination of anticancer tyrosine kinase inhibitors (TKIs) dasatinib, erlotinib, gefitinib, imatinib, lapatinib, nilotinib, sorafenib and sunitinib in human plasma was developed using high-performance liquid chromatography and detection with tandem mass spectrometry (HPLC-MS/MS). Stable isotopically labeled compounds of the eight different TKIs were used as internal standards. Plasma proteins were precipitated and an aliquot of supernatant was directly injected onto a reversed phase chromatography system consisting of a Gemini C18 column (50 × 2.0 mm i.d., 5.0 µm particle size) and then compounds were eluted with a gradient. The outlet of the column was connected to a triple quadrupole mass spectrometer with electrospray interface. Ions were detected in the positive multiple reaction monitoring mode. This method was validated over a linear range from 20.0 to 10,000 ng/mL for erlotinib, gefitinib, imatinib, lapatinib, nilotinib and sorafenib, and from 5.00 to 2500 ng/mL for dasatinib and sunitinib. Results from the validation study demonstrated good intra- and inter-assay accuracy (<13.1%) and precision (10.0%) for all analytes. This method was successfully applied for routine therapeutic drug monitoring purposes in patients treated with the investigated TKIs.

Quantitative determination of erlotinib and O-desmethyl erlotinib in human EDTA plasma and lung tumor tissue.

BACKGROUND: To increase knowledge about lung tumor tissue levels of erlotinib and its primary active metabolite, and about erlotinib plasma levels in intercalated dosing schedules, a sensitive and accurate method for determination of erlotinib and O-desmethyl erlotinib (OSI-420) in human plasma and lung tumor tissue has been developed. RESULTS: A method with HPLC-MS/MS was validated over a linear range from 5 to 2500 ng/ml in plasma and from 5.0 to 500 ng/ml for lung tumor tissue homogenate (50-5000 ng/g for lung tumor). Calibration curves in plasma were used to quantify analytes in lung tumor tissue homogenate. Lung tumor tissue of 15 patients has been collected and analyzed with the presented method. CONCLUSION: This method has been successfully validated and applied to determine plasma and lung tumor tissue concentrations of erlotinib and O-desmethyl erlotinib in patients with non-small-cell lung cancer.

Fatal interstitial lung disease associated with high erlotinib and metabolite levels. A case report and a review of the literature.

INTRODUCTION: Erlotinib is an agent in the class of oral epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors. Although this class of agents is considered to be relatively safe, the most serious, but rare, adverse reaction is drug-associated interstitial lung disease (ILD). This potentially fatal adverse reaction has been often described with gefitinib, but has been less well described for erlotinib. We here describe a case report of fatal interstitial lung disease in a Caucasian man associated with erlotinib and high erlotinib and metabolite plasma levels and discuss it in the context of all documented cases of erlotinib associated ILD. METHODS: Our case was described and for the literature review a Pubmed and Google Scholar search was conducted for cases of erlotinib associated ILD. The retrieved publications were screened for relevant literature. RESULTS: Besides our case, a total of 19 cases of erlotinib-associated ILD were found. Eleven out 19 cases had a fatal outcome and in only one case erlotinib plasma concentrations were measured and found to be high. CONCLUSION: Erlotinib-associated ILD is a rare, serious and often fatal adverse reaction. Most likely, the cause for erlotinib-associated ILD is multifactorial and high drug levels may be present in patients without serious adverse reactions. However, considering the pharmacology of EGFR inhibitors, high drug and metabolite levels may play a role and future studies are warranted to identify risk factors and to investigate the role of elevated levels of erlotinib and its metabolites in the development of pulmonary toxicity.