Application of a stochastic model to response assessments in a study of squamous cell carcinoma of the head and neck.

This paper discusses the application of a stochastic model in the analysis of response assessments made at various time points in a clinical trial of patients with squamous cell carcinoma of the head and neck. The transition rates and probabilities during treatment administration are derived using maximum likelihood methods. The results are then compared with the standard analyses used in solid tumour studies. Stochastic modelling is considered to complement the standard analyses, provide a holistic approach and better explain the underlying disease process.

Eltrombopag for the treatment of chronic idiopathic thrombocytopenic purpura.

BACKGROUND: The pathogenesis of chronic idiopathic thrombocytopenic purpura (ITP) involves antibody-mediated platelet destruction and reduced platelet production. Stimulation of platelet production may be an effective treatment for this disorder. METHODS: We conducted a trial in which 118 adults with chronic ITP and platelet counts of less than 30,000 per cubic millimeter who had had relapses or whose platelet count was refractory to at least one standard treatment for ITP were randomly assigned to receive the oral thrombopoietin-receptor agonist eltrombopag (30, 50, or 75 mg daily) or placebo. The primary end point was a platelet count of 50,000 or more per cubic millimeter on day 43. RESULTS: In the eltrombopag groups receiving 30, 50, and 75 mg per day, the primary end point was achieved in 28%, 70%, and 81% of patients, respectively. In the placebo group, the end point was achieved in 11% of patients. The median platelet counts on day 43 for the groups receiving 30, 50, and 75 mg of eltrombopag were 26,000, 128,000, and 183,000 per cubic millimeter, respectively; for the placebo group the count was 16,000 per cubic millimeter. By day 15, more than 80% of patients receiving 50 or 75 mg of eltrombopag daily had an increased platelet count. Bleeding also decreased during treatment in these two groups. The incidence and severity of adverse events were similar in the placebo and eltrombopag groups. CONCLUSIONS: Eltrombopag increased platelet counts in a dose-dependent manner in patients with relapsed or refractory ITP. (ClinicalTrials.gov number, NCT00102739.)

Target-specific randomized discontinuation trial design: a novel approach in molecular therapeutics.

PURPOSE: To describe a phase II study design to evaluate the activity of novel anti-cancer agents that focuses on molecular pathogenesis rather than tumor histology. METHODS: We propose an enrichment design that enrolls patients across histologies expressing target X and incorporates randomized discontinuation of drug Y after an initial treatment period to evaluate for potential cystostatic activity. RESULTS: We are currently evaluating the activity of lapatinib in patients with HER-2 amplified solid tumors using the target-specific, histology-independent, randomized discontinuation design. Patients receive treatment with lapatinib for an initial 12-week period. After restaging, patients with disease progression are removed from study, patients achieving an objective response continue treatment, and patients with stable disease are randomized to continue lapatinib versus initiate treatment with placebo. The primary endpoints are to evaluate the objective response rate during the initial treatment period and to evaluate the proportion of patients progression-free 12 weeks post-randomization. CONCLUSION: The target-specific, histology-independent, randomized discontinuation design is an attractive alternative to the traditional phase II design for the development of "targeted" therapeutics.

Randomized phase II multicenter trial of two schedules of lapatinib as first- or second-line monotherapy in patients with advanced or metastatic non-small cell lung cancer.

PURPOSE: This randomized phase II study was initially designed to test the activity of two dose schedules of lapatinib (GW572016H), an oral, reversible, dual tyrosine kinase inhibitor of epidermal growth factor receptor (EGFR) and human EGFR-2 (HER2/neu; HER2), in chemotherapy-naive patients with non-small cell lung cancer (NSCLC); it was later amended to target patients with bronchioloalveolar carcinoma or no smoking history. EXPERIMENTAL DESIGN: Patients with good performance status and recurrent or metastatic NSCLC were randomized to lapatinib (orally, 1,500 mg once daily or 500 mg twice daily) until progression or intolerance. Patients could have had a maximum of one prior systemic therapy (chemotherapy or biological therapy) for NSCLC. Safety and activity were assessed every 4 and 8 weeks, respectively. Tumors were analyzed for EGFR and HER2 mutations and/or amplifications. RESULTS: Of 75 patients in the nontargeted population, 1 (1.3%) had partial response and 16 (21%) had stable disease of >or=24 weeks. No complete or partial responses were observed in 56 patients in the targeted population; 14 (25%) had stable disease of >or=24 weeks. No responses were seen in three patients with EGFR mutations and five with EGFR gene amplification. No mutations in HER2 were found. One of two patients with HER2 amplification had a 51% decrease in tumor size; however, this response was unconfirmed. The most common adverse events were grade 1 or 2 diarrhea, rash, fatigue, nausea, and anorexia. Adverse events were similar across dosing regimens. CONCLUSIONS: Lapatinib was well tolerated, with no notable difference in toxicity between treatment groups. Lapatinib monotherapy did not induce a significant number of tumor regressions in NSCLC. Further studies may be warranted to determine whether lapatinib is active in combination with other agents in the treatment of NSCLC.