Drug cost avoidance in clinical trials of breast cancer.

BACKGROUND: The objectives of this study were to determine if clinical trials in breast cancer, with an investigational drug, created direct drug cost savings for the healthcare system related to cost avoidance of the best standard of care treatments used in these studies. The aim was to quantify this potential drug cost avoidance. METHODS: We conducted a retrospective observational study of the drug cost avoidance during the study period (2014-2016). We included clinical trials with investigational drug, managed by pharmacy department and provided by the sponsor. The patients included had a therapeutic alternative defined as standard treatment that should have been received in case of not participating in the clinical trial. Direct cost savings, to national healthcare system, associated to clinical trials were calculated. RESULTS: Thirty-seven clinical trials with a total of 89 breast cancer patients were included in the study. A total of 62.2% were phase III and 75.7% belonged to the pharmaceutical industry. They provided a total cost avoidance of 957,246€ (1,130,028$), an average cost avoidance per patient of 10,756€ (12,697$). CONCLUSIONS: Our study suggests that those clinical trials in which investigational drug are provided or refunded by the sponsor provide substantial cost savings. Due to the shortage of published articles that calculate the cost avoided in medication, we cannot compare directly the results obtained in the different institutions.

Increased INR after gefitinib and acenocoumarol co-administration.

INTRODUCTION: Drug interactions can cause many clinical problems, particularly when the drugs are administered in combination with anticancer agents. CASE REPORT: A patient required two hospitalizations due to risk of bleeding with altered INR probably due to an interaction between gefitinib and acenocoumarol, which resulted in the potentiation of the effect of the latter and acenocoumarol dose adjustment was needed. A causality assessment between the drug-drug interaction and the augmented INR was conducted according to Naranjo algorithm and was classified as a definite adverse drug reaction. CONCLUSIONS: Patient's management recommended is to closely monitor for changes in the effects of coumarin derivatives, if administered concomitantly with antineoplasic agents.

[Validation of genetic polymorphisms associated to the toxicity of chemotherapy in colorectal cancer patients]. / Validación de polimorfismos genéticos asociados a toxicidad al tratamiento quimioterápico en pacientes de cáncer colorrectal.

OBJECTIVE: To validate the associations previously found in three cohorts of patients from the General University Hospital Gregorio Marañón, between the polymorphisms rs1128503, rs2032582 and rs1045642 of the ABCB1 gene and the hand-foot syndrome and diarrhea in colorectal cancer patients treated with chemotherapy regimes containing Capecitabine and 5-Fluorouracil, respectively, and between the polymorphisms rs2297595 of the DPYD gene and nausea/vomiting, rs11615 of ERCC1 and neutropenia, and rs28399433 CYP2A6 and neutropenia, in colorectal cancer patients treated with FOLFOX or XELOX as adjuvant therapy. METHOD: Colorectal cancer patients treated with chemotherapy regimes, containing Capecitabine (n = 157), 5-Fluorouracil (n = 99) were included in the study, as well as patients treated with XELOX or FOLFOX (n = 83) as adjuvant therapy. The patients included were recruited from the Doce de Octubre University Hospital and from the Gregorio Marañón General University Hospital, and signed the informed consent form. DNA was obtained from blood samples. Genotyping was carried out with SNaPshot. Contingency tables were created for analyzing the associations between the genotypes and the adverse reactions. RESULTS: None of the associations previously identified was replicated in the validation cohort. CONCLUSIONS: Pharmacogenetic studies with a limited sample size must be validated with bigger cohorts, if possible by means of multicentre studies, reducing the variables to the maximum and should never be used in clinical practice without validation.

OBJETIVO: Validar las asociaciones, encontradas previamente en tres cohortes de pacientes del Hospital General Universitario Gregorio Marañón, entre los polimorfismos rs1128503, rs2032582 y rs1045642 del gen ABCB1 con síndrome manopie y diarrea en pacientes de cáncer colorrectal tratados con regímenes que contenían capecitabina y 5-Fluorouracilo, respectivamente, y entre los polimorfismos rs2297595 del gen DPYD con nauseas/vómitos, rs11615 ERCC1 y neutropenia, y rs28399433 CYP2A6 y neutropenia en pacientes de cáncer colorrectal tratados con FOLFOX o XELOX en adyuvancia. MÉTODO: Se incorporaron al estudio pacientes de cáncer colorrectal tratados con regímenes quimioterápicos que contenían capecitabina (n = 157), 5-fluorouracilo (n = 99) y pacientes tratados en adyuvancia con XELOX o FOLFOX (n = 83). Los pacientes participantes fueron reclutados en el Hospital Universitario Doce de Octubre y en el Hospital General Universitario Gregorio Marañón tras firmar consentimiento informado. Se extrajo ADN a partir de muestras de sangre. Los genotipados se realizaron mediante SNaPshot. Se realizaron tablas de contingencia para analizar las asociaciones entre genotipos y reacciones adversas. RESULTADOS: Ninguna de las asociaciones previamente identificadas fue replicada en la cohorte de validación. CONCLUSIONES: Los estudios farmacogenéticos con un tamaño muestral limitado deben ser validados en cohortes más numerosas, a ser posible en estudios multicéntricos, reduciendo al máximo las variables y nunca deben ser utilizados en clínica sin validar.