Potential Pharmacokinetic Drug-Drug Interactions between Cannabinoids and Drugs Used for Chronic Pain.

Choosing an appropriate treatment for chronic pain remains problematic, and despite the available medication for its treatment, still, many patients complain about pain and appeal to the use of cannabis derivatives for pain control. However, few data have been provided to clinicians about the pharmacokinetic drug-drug interactions of cannabinoids with other concomitant administered medications. Therefore, the aim of this brief review is to assess the interactions between cannabinoids and pain medication through drug transporters (ATP-binding cassette superfamily members) and/or metabolizing enzymes (cytochromes P450 and glucuronyl transferases).

[Current status and regulation of bioanalytical laboratories engaged in quantifying immunosuppressants for transplant patients in Argentina]. / Estado de situación y regulación de laboratorios bioanalíticos que cuantifican inmunosupresores para trasplantes en Argentina.

Objective Determine the status of analytical laboratories that quantify immunosuppressants in transplant patients who are under therapeutic drug monitoring (TDM) for these drugs in Argentina in order to identify potential perfectible areas for action. Methods A survey of the clinical and analytical TDM centers in Argentina was conducted between September 2013 and November 2014 under the direction of the Garrahan Hospital Clinical Pharmacokinetics Unit and the National Unified Central Institute for Ablation and Implant Coordination. Results A nationally representative sample of 27 clinical and analytical centers was identified, of which 45% were public hospitals. Most of these centers (95%) monitor ciclosporin and tacrolimus, and to a lesser extent, sirolimus and everolimus; a small number of them also monitor mycophenolic acid. The median number of samples of these five drugs analyzed per month was 251 (range: 10-2024). Nearly 60% of the samples were analyzed in private institutions. Only four of the respondents (17%) reported values within the therapeutic margin. Of all the centers, 92% use immunoassay as the analytical methodology. Of the bioanalytical installations that have their own facilities, 68% reported that they also have their own quality assurance program. Conclusions TDM of immunosuppressants is a recommended practice for transplant patients in Argentina. Initiatives need to be taken at the national level to develop uniform guidelines for analytical laboratories that include TDM-related quality assurance processes with regulatory force. There is also a need to train technical and professional personnel and to invite the participation of public and private organizations in the regulatory, public health, and research areas.

Estado de situación y regulación de laboratorios bioanalíticos que cuantifican inmunosupresores para trasplantes en Argentina / Current status and regulation of bioanalytical laboratories engaged in quantifying immunosuppressants for transplant patients in Argentina

RESUMEN Objetivo Establecer el estado de situación de los laboratorios analíticos que cuantifican inmunosupresores en pacientes con trasplantes que se encuentran bajo monitoreo terapéutico de drogas (TDM) de estos fármacos en Argentina, para establecer potenciales áreas de actuación perfectibles. Métodos Se realizó una encuesta en centros clínicos y analíticos de TDM de Argentina, coordinada por la Unidad de Farmacocinética Clínica del Hospital Garrahan y el Instituto Nacional Central Único Coordinador de Ablación e Implante, desde setiembre de 2013 hasta noviembre de 2014. Resultados Se incluyeron 27 centros clínicos y analíticos (muestra representativa nacional). El 45% fueron hospitales públicos. La mayoría (95%) monitorizan ciclosporina y tacrolimús; en menor medida, sirolimús y everolimús, y muy pocos el ácido micofenólico. La cantidad (mediana, rango) de muestras analizadas por mes para estos cinco fármacos fue de 251 (10 - 2024). Casi 60% de las muestras se analizaron en instituciones privadas. Solo cuatro (17%) de los encuestados informan valores del margen terapéutico. El 92% usa inmunoensayos como metodología analítica. El 68% de los encuestados que contaban con instalaciones bioanalíticas propias informaron poseer algún programa de garantía de calidad. Conclusiones El TDM de inmunosupresores es una práctica recomendada para pacientes con trasplante en Argentina. Se requiere generar iniciativas nacionales que desarrollen guías armonizadas para laboratorios analíticos que incluyan procesos de garantía de calidad con alcance regulatorio relacionados con el TDM. Por otra parte, también es necesario capacitar al personal técnico y profesional, e invitar a participar a organizaciones públicas y privadas del ámbito regulatorio, sanitario y de la investigación.

ABSTRACT Objective Determine the status of analytical laboratories that quantify immunosuppressants in transplant patients who are under therapeutic drug monitoring (TDM) for these drugs in Argentina in order to identify potential perfectible areas for action. Methods A survey of the clinical and analytical TDM centers in Argentina was conducted between September 2013 and November 2014 under the direction of the Garrahan Hospital Clinical Pharmacokinetics Unit and the National Unified Central Institute for Ablation and Implant Coordination. Results A nationally representative sample of 27 clinical and analytical centers was identified, of which 45% were public hospitals. Most of these centers (95%) monitor ciclosporin and tacrolimus, and to a lesser extent, sirolimus and everolimus; a small number of them also monitor mycophenolic acid. The median number of samples of these five drugs analyzed per month was 251 (range: 10-2024). Nearly 60% of the samples were analyzed in private institutions. Only four of the respondents (17%) reported values within the therapeutic margin. Of all the centers, 92% use immunoassay as the analytical methodology. Of the bioanalytical installations that have their own facilities, 68% reported that they also have their own quality assurance program. Conclusions TDM of immunosuppressants is a recommended practice for transplant patients in Argentina. Initiatives need to be taken at the national level to develop uniform guidelines for analytical laboratories that include TDM-related quality assurance processes with regulatory force. There is also a need to train technical and professional personnel and to invite the participation of public and private organizations in the regulatory, public health, and research areas.

Therapeutic monitoring of pediatric renal transplant patients with conversion to generic cyclosporin.

BACKGROUND: Cyclosporin is a calcineurin inhibitor widely used in renal transplant patients to prevent organ rejection. Several position papers have been published but no reports on the practical experience in pediatric patients undergoing conversion between cyclosporin innovator and generic products are available. OBJECTIVE: To evaluate the pharmacokinetics and safety as part of therapeutic monitoring of cyclosporin in renal transplant pediatric patients who switch from the innovator to the generic formulation in Argentina. SETTING: Hospital de Pediatría JP Garrahan, Buenos Aires, Argentina. METHODS: Stable pediatric renal transplant patients (6 months post-transplant) switched from the innovator to the generic formulation of cyclosporin microemulsion capsule. Cyclosporin pharmacokinetic parameters were obtained while taking the innovator and after starting with the generic formulation. Blood samples were drawn before and 1, 2, and 3 h after drug administration and subsequently quantified. Pharmacokinetic parameters were obtained by means of a Bayesian approach. MAIN OUTCOMES MEASURE: Cyclosporin pharmacokinetic parameters (area under the curve, AUC; Blood concentration after 2 h, C2), adverse events and graft rejection. RESULTS: A total of 12 patients were included. Median (range) age and time post-transplant were 10.7 years (6.5-17.7) and 8.3 years (3.4-14.0), respectively. Two patients or their parents did not consent to the switch. Median (range) dose normalized cyclosporin AUC and C2 were 1.15 (mg*h/L)/mg/kg (0.72-3.0) and 265.5 (ng/ml)/mg/kg (120.8-725.7), respectively, on the innovator therapy and 1.05 (mg*h/L)/mg/kg (0.54-2.22) and 317.1 (ng/ml)/mg/kg (116.7-564.7) for the generic drug after the switch. The median (range) percentage of change in the AUC and C2 when switching between formulations were 16.7 % (0.7-56.7) and 13.1 % (3.7-68.6), respectively. No significant changes in serum creatinine levels were registered when comparing before and after substitution of products. Adverse events (number of events) recorded 5 months before and after the switch included hirsutism (2), hypertension (2), and gingival hyperplasia (1). CONCLUSION: Conversion of cyclosporin from innovator brand to generic in pediatric renal transplant patients needs to be closely monitored.