Marcelo Capra

DBS sampling in imatinib therapeutic drug monitoring: from method development to clinical application

BACKGROUND Imatinib (IM) is widely used in treatment of chronic myeloid leukemia with target trough plasma concentrations above 1000 ng ml(-1). DBS can increase access to IM therapeutic drug monitoring. RESULTS IM was measured in the range 50-4000 ng ml(-1) by UHPLC-MS/MS using one 6 mm DBS in a fully validated method. IM was stable at DBS maintained at 40°C for 36 days. Plasma and DBS concentrations were highly correlated (r > 0.96). The use of a IM concentration target of 765 ng ml(-1) in DBS identified 93% of patients with plasma concentration below 1000 ng ml(-1). CONCLUSION IM can be measured in DBS using UHPLC-MS/MS with results comparable to those obtained in blood plasma.

First report of imatinib measurement in hair: Method development and preliminary evaluation of the relation between hair and plasma concentrations with therapeutic response in chronic myeloid leukemia

BACKGROUND Imatinib (IM) is a first choice drug for treatment of chronic myeloid leukemia (CML), with a widely accepted concentration threshold of 1000ng/ml being used as a target for therapeutic drug monitoring. Once adherence to the pharmacotherapeutic regimen is of paramount importance during the long treatment course of CML, the measurement of hair IM concentrations could be a surrogate of the patients exposure to the drug. METHODS IM was extracted from a 5mg hair sample by a liquid-liquid extraction with ethyl acetate, and IM-d8 was used as internal standard (IS). After evaporation, and reconstitution in acetonitrile, the extract was injected into a LC-MS/MS system. Compounds were eluted on a C8 column in isocratic mode. IM and IS were identified in positive electrospray ionization mode using ion transitions of m/z 494.5>394.5 and 503.0>394.3 respectively. The method was applied to 102 paired hair and samples obtained from CML patients. Treatment response was evaluated according to the European LeukemiaNet recommendations. RESULTS The assay was validated in the concentration range of 0.5-25ng/mg, with intra- and inter-assay imprecisions of <13.1% and <9.3%, respectively. The limits of quantification and detection were 0.5 and 0.15ng/mg, respectively. Median hair IM concentrations are significantly smaller in patients with therapeutic failure when compared with patients with partial or optimal response (4.63 vs. 7.93, p=0.040), the same trend presented by median plasma IM concentrations (629.5 vs. 1084.8, p=0.009). An IM hair concentration below 5.8ng/mg has 83% sensibility and 70% specificity to identify patients with therapeutic failure. CONCLUSIONS A fast, sensitive, and selective LC-MS/MS method allowing quantification of IM in hair samples was developed and validated. CML patients with therapeutic failure had significantly lower hair IM concentrations when compared with patients with optimal response. These preliminary findings may support the use of hair as a matrix for IM monitoring in clinical settings, with significant logistic advantages over the collection of venous blood, particularly in developing countries.

ETV6/RUNX1 fusion lacking prognostic effect in pediatric patients with acute lymphoblastic leukemia

A Brazilian sample of 58 patients with acute lymphoblastic leukemia has been prospectively followed up with the objective of evaluating evolution of disease. Age ranged from 6 months to 16 years. Of the 58 patients, 11 were positive and 47 were negative for the ETV6/RUNX1 fusion (previously known as TEL/AML1). After a minimum follow-up period of 57 months, 2 of the ETV6/RUNX1(+) patients had died and 11 of the ETV6/RUNX1(-), for an overall survival of 77.6%. Among the 11 ETV6/RUNX1(+) patients (age range, 2 years to 13 years 7 months), all achieved a complete remission; the average overall survival was 64.2 months and the average event-free survival was 61.7 months. Among the 47 ETV6/RUNX1(-) patients, 4 did not have a complete remission; the average overall survival was of 60.8 months and the average event-free survival was 57.2 months. No significant difference was observed between overall survival and event-free survival, nor in any of the other data comparatively analyzed. The patients had a cure rate similar to that described in literature. In this small sample population, the presence of the ETV6/RUNX1 fusion did not identify statistical difference in prognosis.

Daratumumab plus bortezomib and dexamethasone versus bortezomib and dexamethasone in relapsed or refractory multiple myeloma: updated analysis of CASTOR

Daratumumab, a CD38 human monoclonal antibody, demonstrated significant clinical activity in combination with bortezomib and dexamethasone versus bortezomib and dexamethasone alone in the primary analysis of CASTOR, a phase 3 study in relapsed and/or refractory multiple myeloma. A post hoc analysis based on treatment history and longer follow up is presented. After 19.4 (range: 0-27.7) months of median follow up, daratumumab plus bortezomib and dexamethasone prolonged progression-free survival (median: 16.7 versus 7.1 months; hazard ratio, 0.31; 95% confidence interval, 0.24-0.39; P<0.0001) and improved the overall response rate (83.8% versus 63.2%; P<0.0001) compared with bortezomib and dexamethasone alone. The progression-free survival benefit of daratumumab plus bortezomib and dexamethasone was most apparent in patients with 1 prior line of therapy (median: not reached versus 7.9 months; hazard ratio, 0.19; 95% con fidence interval, 0.12-0.29; P<0.0001). Daratumumab plus bortezomib and dexamethasone was also superior to bortezomib and dexamethasone alone in subgroups based on prior treatment exposure (bortezomib, thalidomide, or lenalidomide), lenalidomide-refractory status, time since last therapy (≤12, >12, ≤6, or >6 months), or cytogenetic risk. Minimal residual disease–negative rates were >2.5-fold higher with daratumumab across subgroups. The safety profile of daratumumab plus bortezomib and dexamethasone remained consistent with longer follow up. Daratumumab plus bortezomib and dexamethasone demonstrated significant clinical activity across clinically relevant subgroups and provided the greatest benefit to patients treated at first relapse. Trial registration: clinicaltrials.gov identifier: 02136134.

Prognostic and therapeutic stratification in CLL: focus on 17p deletion and p53 mutation.

Chronic lymphocytic leukemia (CLL), a disorder for which B cell heterogeneity and increased cellular proliferation play central pathogenic roles, displays several genetic abnormalities that are associated with poor prognosis and have therapeutic implications. In this review, we discuss the prognostic role and therapeutic implications of chromosome 17p deletions and TP53 mutations in CLL. Unlike other recurrent genetic abnormalities, the frequency of TP53 alterations is relatively low in newly diagnosed patients, but increases sharply with disease progression, which suggests that these alterations represent an evolutionary mechanism of resistance. In comparison with patients without such abnormalities, those with 17p deletions and TP53 mutations have lower response rates and more aggressive disease. One important consequence of the diverse molecular mechanisms that affect the TP53 pathway is the need to assess both the presence of 17p deletion and TP53 mutations before treatment initiation. Several authors have attempted to incorporate TP53 abnormalities in different prognostic models for CLL, and the recent International Prognostic Index for Chronic Lymphocytic Leukemia formally considers patients with TP53 abnormalities (deletion 17p or TP53 mutation or both) as high-risk. Several novel agents may improve results in patients with CLL, including in those with TP53 mutations. Ibrutinib, idelalisib, and venetoclax have been approved in various settings and countries for treatment of CLL. Further progress in targeted therapy and judicious use of chemotherapy, monoclonal antibodies, and reduced-intensity allogeneic transplantation will provide patients with CLL in general, and those with TP53 abnormalities in particular, with a better prognosis.

Needs for Palliative Care of Cancer Patients in Brazil: Analysis of Data from 2008-2014

Background: The Brazilian Health System (SUS) faces major challenges to ensure the constitutional right of universal access to health care assistance and technological advances to the entire population. Concerns with the ageing population, the increasing incidence of cancer and the emergence of chronic non-communicable diseases include palliative care as one of the objectives of the Brazilian Health System (SUS). However, considering that each disease and individual present different social and cultural factors, needs, pattern of disease progression, associated co-morbidities and access to health care, the estimation of necessary resources and the definition of specific criteria to structure and adapt palliative care in the health services have been a difficult task in Brazil. Thus, it is necessary to estimate the needs and the resources and to specify parameters to structure and tailor an adequate modality of assistance in palliative care. Aims: 1) To estimate the number of cancer patients with palliative care needs in the population; 2) To simulate palliative care methods for population based estimation. Methods: The present methodology has a quantitative approach, with descriptive, exploratory, retrospective and observational studies of hospitalized cancer patients. This is a cross-sectional study using death certificate and hospital admission data, which was collected from the Mortality Information System (SIM) and Hospital Information System (SIH) of the Brazilian Health System (SUS), obtained from the database of the Health Information Department (DATASUS). Results: Yearly around 1.1 million deaths were reported to the Brazilian Mortality Information System, being 15.9% of these related to people living with cancer. Between 2008 and 2014, there were almost 4.5 million hospitalizations (4,431,685) of patients with cancer in Brazil, and, of all the hospital admissions of cancer patients, 1.189.908 (26.85%) were related to intercurrences of the disease and/or of treatment. The average rate of hospital mortality was 7.7 for cancer in general and 21.4 for clinical intercurrence of cancer patients, while the average length of stay (LOS) was 5.7 days for cancer in general and 7.9 days for clinical intercurrence of cancer patients. Conclusion: considering that the offer and the technical guidance regarding palliative care for users served by health establishments authorized by Brazilian Health System for the specialized assistance in oncology are mandatory, we need to estimate the needs, resources and specify parameters to structure and tailor an adequate modality of assistance in palliative care.