R and Shiny for Cost-Effectiveness Analyses: Why and When? A Hypothetical Case Study.

INTRODUCTION: Health economics models are typically built in Microsoft Excel® owing to its wide familiarity, accessibility and perceived transparency. However, given the increasingly rapid and analytically complex decision-making needs of both the pharmaceutical industry and the field of health economics and outcomes research (HEOR), the demands of cost-effectiveness analyses may be better met by the programming language R. OBJECTIVE: This case study provides an explicit comparison between Excel and R for contemporary cost-effectiveness analysis. METHODS: We constructed duplicate cost-effectiveness models using Excel and R (with a user interface built using the Shiny package) to address a hypothetical case study typical of contemporary health technology assessment. RESULTS: We compared R and Excel versions of the same model design to determine the advantages and limitations of the modelling platforms in terms of (i) analytical capability, (ii) data safety, (iii) building considerations, (iv) usability for technical and non-technical users and (v) model adaptability. CONCLUSIONS: The findings of this explicit comparison are used to produce recommendations for when R might be more suitable than Excel in contemporary cost-effectiveness analyses. We conclude that selection of appropriate modelling software needs to consider case-by-case modelling requirements, particularly (i) intended audience, (ii) complexity of analysis, (iii) nature and frequency of updates and (iv) anticipated model run time.

Relationship of response and survival in patients with relapsed and refractory multiple myeloma treated with pomalidomide plus low-dose dexamethasone in the MM-003 trial randomized phase III trial (NIMBUS).

Relapsed/refractory multiple myeloma (RRMM) patients have poor overall survival (OS). Pomalidomide plus low-dose dexamethasone (POM + LoDEX) significantly extends OS in RRMM vs. high-dose dexamethasone. Survival of patients with stable disease (SD) was compared to patients with progressive disease (PD) or ≥ partial response (≥PR) at cycles (C) 3, 5, and 7. Among 302 patients randomized to POM + LoDEX, at C3 19.2% achieved ≥ PR, 38.4% SD, and 14.6% PD. Patients with SD at C3 (17.4%) and C5 (13.6%) showed improved responses at C7. Median OS from randomization by response at C3 was 22.4 months for ≥ PR (n = 58, HR 0.66; 95% CI 0.40-1.08, p = 0.0976 vs. SD), 16.2 months for SD (n = 116), and 6.3 months for PD (n = 44, HR 3.43; 95% CI 2.23-5.27, p < 0.0001 vs. SD). Similar patterns were observed for C5 and C7. Results show that POM + LoDEX should be a standard treatment after lenalidomide and bortezomib, including in SD patients.

Phase I evaluation of cediranib, a selective VEGFR signalling inhibitor, in combination with gefitinib in patients with advanced tumours.

AIM: Cediranib is a highly potent inhibitor of vascular endothelial growth factor receptor (VEGFR) signalling. Preclinical and clinical data suggest that inhibition of the VEGFR and epidermal growth factor receptor (EGFR) pathways may be synergistic. Combination treatment with cediranib and gefitinib, an EGFR signalling inhibitor, was evaluated in patients with advanced solid tumours. PATIENTS AND METHODS: Ninety patients received treatment in this four-part, open-label study (NCT00502060). The patients received once-daily oral doses of cediranib (20-45mg) and gefitinib 250mg (part A1; n=16) or 500mg (part B1; n=44). A cohort expansion phase investigated the potential pharmacokinetic interaction of cediranib 30mg with gefitinib 250mg (part A2; n=15) or 500mg (part B2; n=15). The primary objective was to assess the safety and tolerability of cediranib with gefitinib. Secondary assessments included pharmacokinetics, efficacy and pharmacodynamics. RESULTS: Combination treatment was generally well tolerated; the protocol-defined maximum-tolerated dose of cediranib was 30mg/day with gefitinib 250mg/day (part A1) and cediranib 45mg/day was the maximum dose investigated with gefitinib 500mg/day (part B1). The most common adverse events were diarrhoea (84 [93%]), anorexia (63 [70%]) and fatigue (60 [67%]). Cediranib pharmacokinetic parameters were not substantially different when given alone or in combination with gefitinib. Gefitinib pharmacokinetic parameters were similar to those seen previously with gefitinib monotherapy. Efficacy results included eight (9%) confirmed partial responses (6 renal; 1 lung; 1 osteosarcoma) and 38 (42%) patients with stable disease. Pharmacodynamic assessments demonstrated changes in levels of VEGF and soluble VEGFR-2 following treatment. CONCLUSIONS: Combination treatment was generally well tolerated and showed encouraging antitumour activity in patients with advanced solid tumours. These results merit further exploration.

Phase I clinical study of AZD2171, an oral vascular endothelial growth factor signaling inhibitor, in patients with advanced solid tumors.

PURPOSE: AZD2171 is a highly potent oral selective inhibitor of vascular endothelial growth factor (VEGF) signaling. This phase I study was designed to evaluate the safety and tolerability of increasing doses of AZD2171, with additional assessments of pharmacokinetics, pharmacodynamics, and efficacy. PATIENTS AND METHODS: In part A, 36 patients with solid tumors and liver metastases refractory to standard therapies received once-daily oral AZD2171 (0.5 to 60 mg). Doses were escalated in successive cohorts until the maximum-tolerated dose was identified. In part B, patients with (n = 36) or without (n = 11) liver metastases were randomly assigned to receive once-daily AZD2171 (20, 30, or 45 mg). In both parts, treatment continued until tumor progression or dose-limiting toxicity (DLT) was observed. RESULTS: Eighty-three patients received AZD2171, which was generally well tolerated at doses of 45 mg/d or less; the most frequently reported dose-related adverse events were diarrhea, dysphonia, and hypertension. The most common DLT was hypertension (n = 7), which occurred at AZD2171 doses of 20 mg and higher. After a single dose, maximum plasma (peak) drug concentration after single-dose administration (Cmax) was achieved 1 to 8 hours postdosing with an arithmetic mean half-life associated with terminal slope of a semilogarithmic concentration-time curve (t1/2 lamda(z)) of 22 hours. Pharmacodynamic assessments demonstrated time-, dose-, and exposure-related decreases in initial area under the curve, defined over 60 seconds post-contrast arrival in the tissue (iAUC60) using dynamic contrast-enhanced magnetic resonance imaging, as well as dose- and time-dependent reductions in soluble VEGF receptor 2 levels. Preliminary evidence of efficacy included two confirmed partial responses and 22 patients with stable disease; effects on tumor size appeared to be dose related. CONCLUSION: Once-daily oral AZD2171 at doses of 45 mg or less was generally well tolerated and was associated with encouraging antitumor activity in patients with a broad range of advanced solid tumors.