RESUMEN
Despite great therapeutic advances in the field of biologics, small synthetic molecules such as thiopurines, including azathioprine, mercaptopurine, and thioguanine, remain an important therapeutic pillar in the treatment of inflammatory bowel disease, other autoimmune disorders, and cancer. This review presents the latest guidelines for thiopurine administration, highlighting the importance of individualized therapy guided by pharmacogenomics. It emphasizes dose adjustment based on nudix hydrolase 15 (NUDT15) and thiopurine S-methyltransferase (TPMT) genotype, along side thiopurine S-methyltransferase activity and thiopurine metabolic profile. In addition, the article takes a critical look at emerging research in the field of thiopurine pharmaco genomics featuring novel genetic markers and technological developments in genetic testing. Finally, the potential of integrated approaches that combine genetic, meta bolic, and clinical factors to further individualize thiopurine therapy is highlighted.
Asunto(s)
Enfermedades Inflamatorias del Intestino , Mercaptopurina , Metiltransferasas , Medicina de Precisión , Humanos , Medicina de Precisión/métodos , Metiltransferasas/metabolismo , Metiltransferasas/genética , Mercaptopurina/uso terapéutico , Mercaptopurina/administración & dosificación , Enfermedades Inflamatorias del Intestino/tratamiento farmacológico , Enfermedades Inflamatorias del Intestino/genética , Azatioprina/administración & dosificación , Farmacogenética , Pirofosfatasas/genética , Pirofosfatasas/metabolismo , Enfermedades Autoinmunes/tratamiento farmacológico , Neoplasias/tratamiento farmacológico , Neoplasias/genética , Genotipo , Tioguanina , Hidrolasas NudixRESUMEN
The thiopurine drugs-azathioprine and mercaptopurine-are purine antimetabolites used for the treatment of autoimmune hepatitis. These drugs undergo metabolism through genetically determined pathways, which influences their effectiveness and toxicity. There is scarce information regarding the clinical effects of measuring drug metabolites in these patients. The goal of the study is to test the clinical significance of measuring thiopurine metabolites in patients unsuccessfully treated with thiopurines. Clinical and laboratory data collected for patients who were treated for autoimmune hepatitis between 2015 and 2018, and did not achieve full remission under thiopurine therapy and had thiopurine metabolite levels measured due to lack of response and suspicious side effects were chosen. We compared clinical and laboratory data before and after the therapy change. The study included 25 tests of thiopurine metabolites in 21 patients. Six tests had therapeutic levels. Three tests showed high levels leading to lowering the drug dose. In 11 cases, levels of 6-thioguanine nucleotide were low; the dose was not changed in 3 of these, and the dose was increased in the remaining 8. Shunting was observed in 5 cases, 2 of which were mild and the dose was not changed. In the remaining 3, the dose was decreased, and allopurinol was added. Significant improvements in liver enzymes were observed following dose adjustments. We showed that, in cases of suboptimal response to thiopurine treatment, measuring thiopurine metabolites had an important role in optimizing therapy. In most patients, changing the dose led to a significant improvement with no need to switch to secondline therapies.
Asunto(s)
Azatioprina , Hepatitis Autoinmune , Inmunosupresores , Mercaptopurina , Humanos , Hepatitis Autoinmune/tratamiento farmacológico , Hepatitis Autoinmune/metabolismo , Hepatitis Autoinmune/sangre , Femenino , Masculino , Mercaptopurina/análogos & derivados , Mercaptopurina/uso terapéutico , Mercaptopurina/metabolismo , Mercaptopurina/sangre , Persona de Mediana Edad , Azatioprina/uso terapéutico , Adulto , Inmunosupresores/uso terapéutico , Anciano , Resultado del Tratamiento , Nucleótidos de Guanina/sangre , Estudios Retrospectivos , Monitoreo de Drogas/métodos , Tionucleótidos/sangreRESUMEN
BACKGROUND AND OBJECTIVE: Thioguanine (TG), azathioprine (AZA), and mercaptopurine (MP) are thiopurine prodrugs commonly used to treat diseases, such as leukemia and inflammatory bowel disease (IBD). 6-thioguanine nucleotides (6-TGNs) have been commonly used for monitoring treatment. High levels of 6-TGNs in red blood cells (RBCs) have been associated with leukopenia, the cutoff levels that predict this side effect remain uncertain. Thiopurines are metabolized and incorporated into leukocyte DNA. Measuring levels of DNA-incorporated thioguanine (DNA-TG) may be a more suitable method for predicting clinical response and toxicities such as leukopenia. Unfortunately, most methodologies to assay 6-TGNs are unable to identify the impact of NUDT15 variants, effecting mostly ethnic populations (e.g., Chinese, Indian, Malay, Japanese, and Hispanics). DNA-TG tackles this problem by directly measuring thioguanine in the DNA, which can be influenced by both TPMT and NUDT15 variants. While RBC 6-TGN concentrations have traditionally been used to optimize thiopurine therapy due to their ease and affordability of measurement, recent developments in liquid chromatography-tandem mass spectrometry (LC-MS/MS) techniques have made measuring DNA-TG concentrations in lymphocytes accurate, reproducible, and affordable. The objective of this systematic review was to assess the current evidence of DNA-TG levels as marker for thiopurine therapy, especially with regards to NUDT15 variants. METHODS: A systematic review and meta-analysis were performed on the current evidence for DNA-TG as a marker for monitoring thiopurine therapy, including methods for measurement and the illustrative relationship between DNA-TG and various gene variants (such as TPMT, NUDT15, ITPA, NT5C2, and MRP4). PubMed and Embase were systematically searched up to April 2024 for published studies, using the keyword "DNA-TG" with MeSH terms and synonyms. The electronic search strategy was augmented by a manual examination of references cited in articles, recent reviews, editorials, and meta-analyses. A meta-analysis was performed using R studio 4.1.3. to investigate the difference between the coefficients (Fisher's z-transformed correlation coefficient) of DNA-TG and 6-TGNs levels. A meta-analysis was performed using RevMan version 5.4 to investigate the difference in DNA-TG levels between patients with or without leukopenia using randomized effect size model. The risk of bias was assessed using the Newcastle-Ottowa quality assessment scale. RESULTS: In this systematic review, 21 studies were included that measured DNA-TG levels in white blood cells for either patients with ALL (n = 16) or IBD (n = 5). In our meta-analysis, the overall mean difference between patients with leukopenia (ALL + IBD) versus no leukopenia was 134.15 fmol TG/µg DNA [95% confidence interval (CI) (83.78-184.35), P < 0.00001; heterogeneity chi squared of 5.62, I2 of 47%]. There was a significant difference in DNA-TG levels for patients with IBD with and without leukopenia [161.76 fmol TG/µg DNA; 95% CI (126.23-197.29), P < 0.00001; heterogeneity chi squared of 0.20, I2 of 0%]. No significant difference was found in DNA-TG level between patients with ALL with or without leukopenia (57.71 fmol TG/µg DNA [95% CI (- 22.93 to 138.35), P < 0.80]). DNA-TG monitoring was found to be a promising method for predicting relapse rates in patients with ALL, and DNA-TG levels are likely a better predictor for leukopenia in patients with IBD than RBC 6-TGNs levels. DNA-TG levels have been shown to correlate with various gene variants (TPMT, NUDT15, ITPA, and MRP4) in various studies, points to its potential as a more informative marker for guiding thiopurine therapy across diverse genetic backgrounds. CONCLUSIONS: This systematic review strongly supports the further investigation of DNA-TG as a marker for monitoring thiopurine therapy. Its correlation with treatment outcomes, such as relapse-free survival in ALL and the risk of leukopenia in IBD, underscores its role in enhancing personalized treatment approaches. DNA-TG effectively identifies NUDT15 variants and predicts late leukopenia in patients with IBD, regardless of their NUDT15 variant status. The recommended threshold for late leukopenia prediction in patients with IBD with DNA-TG is suggested to be between 320 and 340 fmol/µg DNA. More clinical research on DNA-TG implementation is mandatory to improve patient care and to improve inclusivity in thiopurine treatment.
Asunto(s)
Monitoreo de Drogas , Nucleótidos de Guanina , Mercaptopurina , Tioguanina , Tionucleótidos , Humanos , Azatioprina/uso terapéutico , Azatioprina/farmacocinética , Biomarcadores/sangre , ADN/genética , Monitoreo de Drogas/métodos , Nucleótidos de Guanina/sangre , Mercaptopurina/farmacocinética , Mercaptopurina/uso terapéutico , Mercaptopurina/sangre , Hidrolasas Nudix , Pirofosfatasas/genética , Pirofosfatasas/metabolismo , Tioguanina/farmacocinética , Tionucleótidos/sangreRESUMEN
Thiopurines, an effective therapy for Crohn's disease (CD), often lead to adverse events (AEs). Gene polymorphisms affecting thiopurine metabolism may predict AEs. This retrospective study in CD patients (n = 114) with TPMT activity > 5 Units/Red Blood Cells analyzed TPMT (c.238 G > C, c.460 G > A, c.719 A > G), ITPA (c.94 C > A, IVS2 + 21 A > C), and NUDT15 (c.415 C > T) polymorphisms. All patients received azathioprine (median dose 2.2 mg/kg) with 41.2% experiencing AEs, mainly myelotoxicity (28.1%). No NUDT15 polymorphisms were found, 7% had TPMT, and 31.6% had ITPA polymorphisms. AEs led to therapy modifications in 41.2% of patients. Multivariate analysis identified advanced age (OR 1.046, p = 0.007) and ITPA IVS2 + 21 A > C (OR 3.622, p = 0.015) as independent predictors of AEs. IVS2 + 21 A > C was also associated with myelotoxicity (OR 2.863, p = 0.021). These findings suggest that ITPA IVS2 + 21 A > C polymorphism and advanced age predict AEs during thiopurine therapy for CD with intermediate-normal TPMT activity.
Asunto(s)
Azatioprina , Enfermedad de Crohn , Metiltransferasas , Pirofosfatasas , Humanos , Enfermedad de Crohn/genética , Enfermedad de Crohn/tratamiento farmacológico , Pirofosfatasas/genética , Femenino , Masculino , Adulto , Estudios Retrospectivos , Azatioprina/efectos adversos , Azatioprina/uso terapéutico , Metiltransferasas/genética , Persona de Mediana Edad , Adulto Joven , Inmunosupresores/efectos adversos , Inmunosupresores/uso terapéutico , Adolescente , Variantes Farmacogenómicas/genética , Polimorfismo de Nucleótido Simple/genética , Polimorfismo Genético/genética , Mercaptopurina/efectos adversos , Mercaptopurina/uso terapéutico , Análisis Multivariante , Anciano , Factores de Riesgo , Hidrolasas Nudix , Inosina TrifosfatasaRESUMEN
BACKGROUND: This study evaluated the effectiveness of NUDT15 codon 139 genotyping in optimizing thiopurine treatment for inflammatory bowel disease (IBD) in Japan, using real-world data, and aimed to establish genotype-based treatment strategies. METHODS: A retrospective analysis of 4628 IBD patients who underwent NUDT15 codon 139 genotyping was conducted. This study assessed the purpose of the genotyping test and subsequent prescriptions following the obtained results. Outcomes were compared between the Genotyping group (thiopurine with genotyping test) and Non-genotyping group (thiopurine without genotyping test). Risk factors for adverse events (AEs) were analyzed by genotype and prior genotyping status. RESULTS: Genotyping test for medical purposes showed no significant difference in thiopurine induction rates between Arg/Arg and Arg/Cys genotypes, but nine Arg/Cys patients opted out of thiopurine treatment. In the Genotyping group, Arg/Arg patients received higher initial doses than the Non-genotyping group, while Arg/Cys patients received lower ones (median 25 mg/day). Fewer AEs occurred in the Genotyping group because of their lower incidence in Arg/Cys cases. Starting with < 25 mg/day of AZA reduced AEs in Arg/Cys patients, while Arg/Arg patients had better retention rates when maintaining ≥ 75 mg AZA. Nausea and liver injury correlated with thiopurine formulation but not dosage. pH-dependent mesalamine reduced leukopenia risk in mesalamine users. CONCLUSIONS: NUDT15 codon 139 genotyping effectively reduces thiopurine-induced AEs and improves treatment retention rates in IBD patients after genotype-based dose adjustments. This study provides data-driven treatment strategies based on genotype and identifies risk factors for specific AEs, contributing to a refined thiopurine treatment approach.
Asunto(s)
Azatioprina , Genotipo , Enfermedades Inflamatorias del Intestino , Mercaptopurina , Pirofosfatasas , Humanos , Pirofosfatasas/genética , Femenino , Masculino , Estudios Retrospectivos , Adulto , Persona de Mediana Edad , Mercaptopurina/uso terapéutico , Mercaptopurina/efectos adversos , Enfermedades Inflamatorias del Intestino/tratamiento farmacológico , Enfermedades Inflamatorias del Intestino/genética , Japón , Azatioprina/efectos adversos , Azatioprina/uso terapéutico , Adulto Joven , Anciano , Inmunosupresores/uso terapéutico , Inmunosupresores/efectos adversos , Adolescente , Factores de Riesgo , Codón , Hidrolasas NudixRESUMEN
Toxic erythema of chemotherapy is a broad but useful diagnosis used to summate the non-infectious, non-allergic, and reproducible reaction of certain chemotherapeutics. Due to overlapping chemotherapy side effects and often multiple drug exposures, identification of a singular culprit drug is challenging for dermatologists. Herein, we report a patient with 6-mercaptopurine (6-MP) toxic erythema confirmed via toxic metabolite markers secondary to increased levels of thiopurine methyltransferase activity, or so called "super shunting." Consulting dermatologists should be aware of "super shunting" in pediatric patients and consider testing for metabolites in patients with toxic acral erythema and mucositis in the setting of 6-MP.
Asunto(s)
Eritema , Mercaptopurina , Metiltransferasas , Mucositis , Humanos , Mercaptopurina/efectos adversos , Mercaptopurina/uso terapéutico , Metiltransferasas/metabolismo , Mucositis/inducido químicamente , Eritema/inducido químicamente , Antimetabolitos Antineoplásicos/efectos adversos , Masculino , Femenino , NiñoRESUMEN
INTRODUCTION: Risk factors for developing pancreatitis due to thiopurines in patients with inflammatory bowel disease (IBD) are not clearly identified. Our aim was to evaluate the predictive pharmacogenetic risk of pancreatitis in IBD patients treated with thiopurines. METHODS: We conducted an observational pharmacogenetic study of acute pancreatitis events in a cohort study of IBD patients treated with thiopurines from the prospectively maintained ENEIDA registry biobank of GETECCU. Samples were obtained and the CASR, CEL, CFTR, CDLN2, CTRC, SPINK1, CPA1, and PRSS1 genes, selected based on their known association with pancreatitis, were fully sequenced. RESULTS: Ninety-five cases and 105 controls were enrolled; a total of 57% were women. Median age at pancreatitis diagnosis was 39 years. We identified 81 benign variants (50 in cases and 67 in controls) and a total of 35 distinct rare pathogenic and unknown significance variants (10 in CEL, 21 in CFTR, 1 in CDLN2, and 3 in CPA1). None of the cases or controls carried pancreatitis-predisposing variants within the CASR, CPA1, PRSS1, and SPINK1 genes, nor a pathogenic CFTR mutation. Four different variants of unknown significance were detected in the CDLN and CPA1 genes; one of them was in the CDLN gene in a single patient with pancreatitis and 3 in the CPA1 gene in 5 controls. After the analysis of the variants detected, no significant differences were observed between cases and controls. CONCLUSION: In patients with IBD, genes known to cause pancreatitis seem not to be involved in thiopurine-related pancreatitis onset.
Asunto(s)
Enfermedades Inflamatorias del Intestino , Pancreatitis , Sistema de Registros , Humanos , Femenino , Pancreatitis/inducido químicamente , Pancreatitis/genética , Masculino , Adulto , Estudios de Casos y Controles , Enfermedades Inflamatorias del Intestino/genética , Enfermedades Inflamatorias del Intestino/tratamiento farmacológico , Persona de Mediana Edad , Predisposición Genética a la Enfermedad , Factores de Riesgo , Variación Genética , Mercaptopurina/efectos adversos , Mercaptopurina/uso terapéuticoRESUMEN
OBJECTIVE: The long-term outcome of thiopurine therapy in patients with ulcerative colitis (UC) enrolled in prospective trials have not been evaluated. We aimed to assess the effects of optimised thiopurine maintenance therapy for UC. METHODS: Long-term data were obtained from patients from our center enrolled in two randomised, prospective, open-label, controlled studies comprising 66 thiopurine-naïve moderate-to-severe patients with UC consisting of a low dose azathioprine (AZA)/allopurinol combination or AZA monotherapy. Following the randomised trials, treatment was adjusted according to adverse effects and metabolites. Patients requiring optimisation initially on AZA monotherapy treatment were switched to low dose AZA in combination with allopurinol, low dose 6-mercaptopurin in combination with allopurinol, or 6-mercaptopurin treatment alone, and those treated with low dose AZA in combination with allopurinol were switched to low dose 6-mercaptopurin in combination with allopurinol or 6-mercaptopurin alone. RESULTS: A total of 62 patients were included in the analysis; 31 were initially treated with AZA monotherapy and 31 with low dose AZA in combination with allopurinol. Initial treatment was tolerated by 67% patients (7 AZA monotherapy and 28 low dose AZA in combination with allopurinol), increasing to 94% (58 patients) post-adjustment. After a median 52-month follow-up period, 38 (93%) out of the 41 primary responding patients-maintained clinical remission without steroids, biologics or surgery. The four intolerant patients and the 17 not responding to optimisation were more likely to require colectomy (odds ratio 16.36; 95% confidence interval 3.08-87.03, p < 0.0001). CONCLUSION: Optimised thiopurine therapy demonstrated effective long-term treatment for patients with ulcerative colitis.
Asunto(s)
Alopurinol , Azatioprina , Colitis Ulcerosa , Quimioterapia Combinada , Mercaptopurina , Humanos , Colitis Ulcerosa/tratamiento farmacológico , Masculino , Femenino , Azatioprina/uso terapéutico , Azatioprina/administración & dosificación , Adulto , Alopurinol/uso terapéutico , Mercaptopurina/uso terapéutico , Mercaptopurina/administración & dosificación , Persona de Mediana Edad , Estudios Retrospectivos , Estudios de Seguimiento , Resultado del Tratamiento , Inmunosupresores/uso terapéutico , Inmunosupresores/administración & dosificación , Índice de Severidad de la Enfermedad , Adulto Joven , Anciano , Ensayos Clínicos Controlados Aleatorios como AsuntoRESUMEN
Despite progressive improvements in the survival rate of pediatric B-cell lineage acute lymphoblastic leukemia (B-ALL), chemoresistance-induced disease progression and recurrence still occur with poor prognosis, thus highlighting the urgent need to eradicate drug resistance in B-ALL. The 6-mercaptopurine (6-MP) is the backbone of ALL combination chemotherapy, and resistance to it is crucially related to relapse. The present study couples chemoresistance in pediatric B-ALL with histidine metabolism deficiency. Evidence was provided that histidine supplementation significantly shifts the 6-MP dose-response in 6-MP-resistant B-ALL. It is revealed that increased tetrahydrofolate consumption via histidine catabolism partially explains the re-sensitization ability of histidine. More importantly, this work provides fresh insights into that desuccinylation mediated by SIRT5 is an indispensable and synergistic requirement for histidine combination therapy against 6-MP resistance, which is undisclosed previously and demonstrates a rational strategy to ameliorate chemoresistance and protect pediatric patients with B-ALL from disease progression or relapse.
Asunto(s)
Linfoma de Burkitt , Leucemia-Linfoma Linfoblástico de Células Precursoras B , Leucemia-Linfoma Linfoblástico de Células Precursoras , Sirtuinas , Humanos , Niño , Mercaptopurina/farmacología , Mercaptopurina/uso terapéutico , Histidina/uso terapéutico , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamiento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras B/tratamiento farmacológico , Linfoma de Burkitt/tratamiento farmacológico , Recurrencia , Progresión de la EnfermedadRESUMEN
Allopurinol can be used in maintenance therapy (MT) for pediatric acute lymphoblastic leukemia (ALL) to mitigate hepatic toxicity in patients with skewed 6-mercaptopurine metabolism. Allopurinol increases the erythrocyte levels of thioguanine nucleotides (e-TGN), which is the proposed main mediator of the antileukemic effect and decreases methyl mercaptopurine (e-MeMP) levels, associated with hepatotoxicity. We investigated the effects of allopurinol in thiopurine methyltransferase (TPMT) wild-type patients without previous clinical signs of skewed 6-mercaptopurine metabolism. Fifty-one patients from Sweden and Finland were enrolled in this prospective before-after trial during ALL MT. Mean e-TGN increased from 280 nmol/mmol hemoglobin (Hb) after 12 weeks of standard MT to 440 after 12 weeks of MT with addition of allopurinol 50 mg/ m2 (P<0.001). Mean e-MeMP decreased simultaneously from 9,481 nmol/mmol Hb to 2,791 (P<0.001) and mean alanine aminotransferase declined by almost 50%. Primary endpoint, defined as e-TGN >200 nmol/mmol Hb, was reached for 91% of the patients after 12 weeks of allopurinol (week 25) compared to 67% before (week 13) (P<0.001). This level was chosen as the median e-TGN in a previous NOPHO ALL-2008 study was just below 200 nmol/mmol Hb. During weeks on allopurinol a slightly higher proportion of the patients had a white blood cell count within target 1.5-3.0×109/L. Allopurinol did not increase severe adverse events and no life-threatening events were reported. In conclusion, allopurinol add-on treatment is safe and leads to increased e-TGN and reduced e-MeMP also in ALL-patients without previous signs of skewed thiopurine metabolism and is a promising approach to increase antileukemic effect and reduce toxicity.
Asunto(s)
Alopurinol , Mercaptopurina , Leucemia-Linfoma Linfoblástico de Células Precursoras , Humanos , Mercaptopurina/administración & dosificación , Mercaptopurina/uso terapéutico , Mercaptopurina/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamiento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Alopurinol/uso terapéutico , Alopurinol/administración & dosificación , Niño , Masculino , Femenino , Preescolar , Adolescente , Estudios Prospectivos , Metiltransferasas/metabolismo , Lactante , Resultado del Tratamiento , Antimetabolitos Antineoplásicos/uso terapéutico , Antimetabolitos Antineoplásicos/efectos adversosRESUMEN
INTRODUCTION: Mercaptopurine (6MP) and methotrexate (MTX) are commonly used for maintenance chemotherapy for acute lymphoblastic leukemia (ALL). These medications have been associated with various side effects such as myelosuppression, colitis, and thyroiditis in addition to numerous cutaneous adverse events. Cutaneous side-effects most reported include mucositis, alopecia, xerosis, and pruritus. We report an interesting case of hand-foot syndrome to 6MP in a child on maintenance therapy for B-cell ALL from an alteration in medication metabolism. CASE: We report a 10-year-old male on maintenance chemotherapy for pre-Bcell ALL who presented to the hospital with worsening oral lesions and erythematous, fissured plaques on the palms and soles. Maintenance therapy consisted of IV vincristine and 5-day pulse of steroids every 12 weeks, daily 6MP, and weekly MTX, which were increased to ≥ 150% of standard dosing due to persistent absolute neutrophil counts > 1500. Metabolites obtained on admission demonstrated elevated 6MMP metabolites at 35,761 (normal < 5700). TPMT and NUDT15 enzyme activity were normal and no alterations in genotyping were discovered. OUTCOME: Patient's oral chemotherapy, including both 6MP and MTX, were stopped and allopurinol 100â mg daily was initiated, which lead to overall improvement. DISCUSSION: Clinical findings of acute mucositis and worsening of hand-foot syndrome, in the setting of inadequate myelosuppression in a child on maintenance therapy for ALL should raise concerns to consider altered metabolism pathway leading to toxic metabolite buildup. Allopurinol can play in improving cutaneous manifestation and chemotherapeutic dosing in patients with altered metabolism.
Asunto(s)
Síndrome Mano-Pie , Mercaptopurina , Metotrexato , Mucositis , Humanos , Masculino , Síndrome Mano-Pie/etiología , Niño , Metotrexato/efectos adversos , Metotrexato/uso terapéutico , Mucositis/inducido químicamente , Mercaptopurina/efectos adversos , Mercaptopurina/uso terapéutico , Mercaptopurina/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamiento farmacológico , Vincristina/efectos adversos , Vincristina/uso terapéutico , Antimetabolitos Antineoplásicos/efectos adversosRESUMEN
Cure rates in pediatric acute lymphoblastic leukemia (ALL) currently approach 90% in the developed world. Treatment involves 6-8 mo of intensive multi-drug chemotherapy followed by 24 mo of maintenance treatment (ALL-MT). The cornerstone of ALL-MT is the daily administration of oral 6-mercaptopurine (6MP), a purine analogue. 6MP is combined with weekly oral methotrexate (MTX), an antifolate drug, to augment therapeutic activity. Some protocols include additional chemotherapy drugs (such as vincristine and corticosteroids) during MT. The objective of ALL-MT is to ensure uninterrupted treatment at the highest tolerated doses of 6MP and MTX. This requires periodic adjustments of 6MP and MTX doses throughout treatment. Tolerance is determined through regular clinical assessments and careful monitoring of blood counts. Tolerated drug doses vary widely among patients, influenced by genetic and non-genetic factors, and require individualized dosing. Suboptimal treatment intensity in ALL-MT is associated with inferior outcomes and results from failure to treat at highest tolerated drug doses and/or interruptions in treatment due to non-adherence or toxicity. Management of MT thus requires close supervision to ensure treatment adherence, periodic drug dose modifications, and treatment to tolerance, while minimizing treatment interruptions due to toxicity. The review highlights these challenges and discusses approaches and strategies for the management of MT, focusing on the Indian context.
Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica , Leucemia-Linfoma Linfoblástico de Células Precursoras , Niño , Humanos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamiento farmacológico , Mercaptopurina/uso terapéutico , Metotrexato/uso terapéuticoRESUMEN
Una paciente pediátrica de 6 años, diagnosticada de leucemia linfoblástica aguda (LLA) de riesgo intermedio, presenta milotoxicidad grave y múltiples infecciones durante la fase de inducción IB del tratamiento con 6-mercaptopurina (6-MP). En las siguientes fases del protocolo de tratamiento, que incluía también 6-MP, la paciente continúa mostrando aplasia de médula ósea y neutropenia, requiriendo numerosos ajustes de dosis e interrupciones. La dosis recomendada de 6-MP se reduce entonces al 5 %. El análisis farmacogenético, realizado en la fase de inducción IB, detectó tres polimorfismos de nucleótido único (SNPs) en el gen que codifica para la enzima tiopurina S-metiltransferasa (TPMT), observándose un fenotipo de metabolizador normal para esta enzima. Como consecuencia, se requirió de un segundo análisis farmacogenético más completo, que reveló polimorfismos patológicos en el gen de la hidrolasa Nudix 15 (NUDT15), explicaría la mielotoxicidad observada en esta paciente. Por ello, un análisis farmacogenético completo debería llevarse a cabo con anterioridad al inicio de 6-MP y de manera rutinaria en la práctica clínica, para conseguir prevenir los efectos adversos graves y/o el fracaso terapéutico. (AU)
A 6-year-old girl diagnosed with intermediate-risk acute lymphoblastic leukemia (ALL) presented with severe my-elotoxicity and multiple infections during phase IB induction treatment with 6-mercaptopurine (6-MP). In the sub-sequent treatment phases, which included 6-MP, the patient continued to show bone marrow aplasia and neu-tropenia, necessitating numerous dose adjustments and interruptions. The recommended dose was eventually reduced to 5 %. A pharmacogenetic analysis, conducted in induction phase IB, detected three single-nucleotide polymorphisms (SNPs) of the thiopurine S-methyltransferase (TPMT) gene, and the phenotype of a normal metab-olizer was observed. As a result of a second pharmacogenetic analysis, pathological polymorphisms were revealed in Nudix hydrolase 15 (NUDT15), which may explain the patients myelotoxicity. Hence, a pharmacogenetic analysis performed in advance would have been able to prevent her from suffering severe toxicity and/or treatment failure. (AU)
Asunto(s)
Humanos , Femenino , Niño , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamiento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Mercaptopurina/uso terapéutico , Pruebas de Farmacogenómica , Farmacogenética , Unión EuropeaRESUMEN
Azathioprine (AZA) therapy failure, though not the primary cause, contributes to disease relapse and progression in inflammatory bowel disease (IBD). However, the role of gut microbiota in AZA therapy failure remains poorly understood. We found a high prevalence of Blautia wexlerae in patients with IBD with AZA therapy failure, associated with shorter disease flare survival time. Colonization of B. wexlerae increased inflammatory macrophages and compromised AZA's therapeutic efficacy in mice with intestinal colitis. B. wexlerae colonization reduced 6-mercaptopurine (6-MP) bioavailability by enhancing selenium-dependent xanthine dehydrogenase (sd-XDH) activity. The enzyme sd-XDH converts 6-MP into its inactive metabolite, 6-thioxanthine (6-TX), thereby impairing its ability to inhibit inflammation in mice. Supplementation with Bacillus (B.) subtilis enriched in hypoxanthine phosphoribosyltransferase (HPRT) effectively mitigated B. wexlerae-induced AZA treatment failure in mice with intestinal colitis. These findings emphasize the need for tailored management strategies based on B. wexlerae levels in patients with IBD.
Asunto(s)
Colitis , Enfermedades Inflamatorias del Intestino , Animales , Ratones , Mercaptopurina/uso terapéutico , Azatioprina/uso terapéutico , Inmunosupresores/uso terapéutico , Disponibilidad Biológica , Enfermedades Inflamatorias del Intestino/tratamiento farmacológico , Colitis/inducido químicamente , Colitis/tratamiento farmacológico , BacteriasRESUMEN
BACKGROUND: Inflammasome has been reported to play an important role in the pathogenesis and progression of hematologic malignancies. As one of the backbone drugs for treating acute lymphoblastic leukemia (ALL), the anti-inflammatory effect of mercaptopurine (6-MP) and the impact of gut microbiome changes caused by 6-MP on anti-inflammasome remain unclear. OBJECTIVE: We aimed to explore the association between 6-MP therapeutic effects and microbiome-involved inflammatory responses in ALL mice models. STUDY DESIGN: ALL murine model was built by i.v. injecting murine L1210 cells into DBA/2 mice (model group). Two weeks after cell injections, 6-MP was orally administrated for 14 days (6-MP group). Fecal samples of mice were collected at different time points. Cecum short-chain fatty acids (SCFAs) concentrations were determined by LC-MS/MS method. Serum cytokines were measured using a cytometric bead array. Gut microbiota composition in mice was explored using 16S rRNA gene sequencing. RESULTS: The anti-tumor effect of 6-MP was proved in ALL mice models. The levels of pro-inflammatory factors IL-6 and TNFα significantly decreased after the administration of 6-MP. Cecum contents' acetate, propionate, and butyrate levels were negatively correlated with IL-6 (correlation coefficient: acetate, -0.24; propionate, -0.26; butyrate, -0.17) and TNFα (correlation coefficient: acetate, -0.45; propionate, -0.42; butyrate, -0.31) changes. Relative abundance changes of f_Lachnospiraceae.g_ASF356 and f_Peptococcaceae.g_uncultured were in accordance with the changes of butyrate levels and opposite to the changes of pro-inflammatory levels. CONCLUSION: The anti-inflammatory response of 6-MP influenced by intestinal microbiota and its metabolites SCFAs, especially butyrate, played an essential role in improving ALL progression.