Clinical usefulness of therapeutic concentration monitoring for imatinib dosage individualization: results from a randomized controlled trial.

PURPOSE: This study assessed whether a cycle of "routine" therapeutic drug monitoring (TDM) for imatinib dosage individualization, targeting an imatinib trough plasma concentration (C min) of 1,000 ng/ml (tolerance: 750-1,500 ng/ml), could improve clinical outcomes in chronic myelogenous leukemia (CML) patients, compared with TDM use only in case of problems ("rescue" TDM). METHODS: Imatinib concentration monitoring evaluation was a multicenter randomized controlled trial including adult patients in chronic or accelerated phase CML receiving imatinib since less than 5 years. Patients were allocated 1:1 to "routine TDM" or "rescue TDM." The primary endpoint was a combined outcome (failure- and toxicity-free survival with continuation on imatinib) over 1-year follow-up, analyzed in intention-to-treat (ISRCTN31181395). RESULTS: Among 56 patients (55 evaluable), 14/27 (52 %) receiving "routine TDM" remained event-free versus 16/28 (57 %) "rescue TDM" controls (P = 0.69). In the "routine TDM" arm, dosage recommendations were correctly adopted in 14 patients (median C min: 895 ng/ml), who had fewer unfavorable events (28 %) than the 13 not receiving the advised dosage (77 %; P = 0.03; median C min: 648 ng/ml). CONCLUSIONS: This first target concentration intervention trial could not formally demonstrate a benefit of "routine TDM" because of small patient number and surprisingly limited prescriber's adherence to dosage recommendations. Favorable outcomes were, however, found in patients actually elected for target dosing. This study thus shows first prospective indication for TDM being a useful tool to guide drug dosage and shift decisions. The study design and analysis provide an interesting paradigm for future randomized TDM trials on targeted anticancer agents

Single agent rituximab in patients with follicular or mantle cell lymphoma: clinical and biological factors that are predictive of response and event-free survival as well as the effect of rituximab on the immune system: a study of the Swiss Group for Clinical Cancer Research (SAKK)

Background: Predictive factors of rituximab efficacy and its effect on the immune system are still not defined. Patients and methods: Three hundred and six patients with follicular or mantle cell lymphoma received four weekly doses of rituximab (induction) and no further treatment (arm A) or four more doses at 2-month intervals (arm B). Results: Response rate to induction was 44%. Independent predictive factors for response were disease bulk <5 cm, follicular histology, normal hemoglobin and low lymphocyte count. Factors associated with event-free survival (EFS) were having responded to induction, having received not more than one line of therapy, Ann Arbor stage I-III, high lymphocyte count, disease bulk <5 cm, Fc-gamma receptor genotype VV and receiving prolonged treatment. B cells were suppressed by treatment but recovered after a median of 12 months in arm A and 18 months in arm B. The median IgM level after 1 year was normal in arm A but was decreased to 73% of baseline in arm B. We observed 24 serious adverse events, equally distributed between arms. Ten patients receiving induction only and six patients receiving prolonged treatment developed a second tumor. Conclusions: We defined the characteristics predicting response and EFS to rituximab. Prolonged treatment results in longer EFS at the cost of a longer reduction in B cell and IgM levels, but without additional clinical toxicit

Clinical usefulness of therapeutic concentration monitoring for imatinib dosage individualization: results from a randomized controlled trial

Purpose: This study assessed whether a cycle of "routine” therapeutic drug monitoring (TDM) for imatinib dosage individualization, targeting an imatinib trough plasma concentration (C min) of 1,000ng/ml (tolerance: 750-1,500ng/ml), could improve clinical outcomes in chronic myelogenous leukemia (CML) patients, compared with TDM use only in case of problems ("rescue” TDM). Methods: Imatinib concentration monitoring evaluation was a multicenter randomized controlled trial including adult patients in chronic or accelerated phase CML receiving imatinib since less than 5years. Patients were allocated 1:1 to "routine TDM” or "rescue TDM.” The primary endpoint was a combined outcome (failure- and toxicity-free survival with continuation on imatinib) over 1-year follow-up, analyzed in intention-to-treat (ISRCTN31181395). Results: Among 56 patients (55 evaluable), 14/27 (52%) receiving "routine TDM” remained event-free versus 16/28 (57%) "rescue TDM” controls (P=0.69). In the "routine TDM” arm, dosage recommendations were correctly adopted in 14 patients (median C min: 895ng/ml), who had fewer unfavorable events (28%) than the 13 not receiving the advised dosage (77%; P=0.03; median C min: 648ng/ml). Conclusions: This first target concentration intervention trial could not formally demonstrate a benefit of "routine TDM” because of small patient number and surprisingly limited prescriber's adherence to dosage recommendations. Favorable outcomes were, however, found in patients actually elected for target dosing. This study thus shows first prospective indication for TDM being a useful tool to guide drug dosage and shift decisions. The study design and analysis provide an interesting paradigm for future randomized TDM trials on targeted anticancer agents

Clinical usefulness of therapeutic concentration monitoring for imatinib dosage individualization: results from a randomized controlled trial.

PURPOSE This study assessed whether a cycle of "routine" therapeutic drug monitoring (TDM) for imatinib dosage individualization, targeting an imatinib trough plasma concentration (C min) of 1,000 ng/ml (tolerance: 750-1,500 ng/ml), could improve clinical outcomes in chronic myelogenous leukemia (CML) patients, compared with TDM use only in case of problems ("rescue" TDM). METHODS Imatinib concentration monitoring evaluation was a multicenter randomized controlled trial including adult patients in chronic or accelerated phase CML receiving imatinib since less than 5 years. Patients were allocated 1:1 to "routine TDM" or "rescue TDM." The primary endpoint was a combined outcome (failure- and toxicity-free survival with continuation on imatinib) over 1-year follow-up, analyzed in intention-to-treat (ISRCTN31181395). RESULTS Among 56 patients (55 evaluable), 14/27 (52 %) receiving "routine TDM" remained event-free versus 16/28 (57 %) "rescue TDM" controls (P = 0.69). In the "routine TDM" arm, dosage recommendations were correctly adopted in 14 patients (median C min: 895 ng/ml), who had fewer unfavorable events (28 %) than the 13 not receiving the advised dosage (77 %; P = 0.03; median C min: 648 ng/ml). CONCLUSIONS This first target concentration intervention trial could not formally demonstrate a benefit of "routine TDM" because of small patient number and surprisingly limited prescriber's adherence to dosage recommendations. Favorable outcomes were, however, found in patients actually elected for target dosing. This study thus shows first prospective indication for TDM being a useful tool to guide drug dosage and shift decisions. The study design and analysis provide an interesting paradigm for future randomized TDM trials on targeted anticancer agents

Pharmacokinetic (PK)-based dosage individualization of imatinib: evaluation of efficiency and clinical usefulness

Background: Retrospective analyses suggest that personalized PK-based dosage might be useful for imatinib, as treatment response correlates with trough concentrations (Cmin) in cancer patients. Our objectives were to improve the interpretation of randomly measured concentrations and to confirm its efficiency before evaluating the clinical usefulness of systematic PK-based dosage in chronic myeloid leukemia patients. Methods and Results: A Bayesian method was validated for the prediction of individual Cmin on the basis of a single random observation, and was applied in a prospective multicenter randomized controlled clinical trial. 28 out of 56 patients were enrolled in the systematic dosage individualization arm and had 44 follow-up visits (their clinical follow-up is ongoing). PK-dose-adjustments were proposed in 39% having predicted Cmin significantly away from the target (1000 ng/ml). Recommendations were taken up by physicians in 57%, patients were considered non-compliant in 27%. Median Cmin at study inclusion was 754 ng/ml and differed significantly from the target (p=0.02, Wilcoxon test). On follow-up, Cmin was 984 ng/ml (p=0.82) in the compliant group. CV decreased from 46% to 27% (p=0.02, F-test). Conclusion: PK-based (Bayesian) dosage adjustment is able to bring individual drug exposure closer to a given therapeutic target. Its influence on therapeutic response remains to be evaluated

Clinical usefulness of therapeutic concentration monitoring for imatinib dosage individualization: Results from the randomized controlled I-COME Trial

Introduction: Imatinib trough plasma concentrations (Cmin) have been correlated with treatment response in chronic myeloid leukemia (CML) patients. The use of Cmin monitoring for optimizing imatinib dosage (therapeutic drug monitoring [TDM]) is therefore proposed for patients with unsatisfying response or tolerance ("rescue TDM"). A cycle of "routine TDM" for dosage individualization could also be beneficial to prevent unfavorable events, yet its clinical usefulness has not been evaluated. We aimed to assess prospectively whether a "routine TDM" intervention targeting imatinib Cmin of 1000 ng/mL (tolerance, 750-1500 ng/mL) could improve efficacy, tolerance, and persistence on treatment compared with "rescue TDM" use only. Patients (or Materials) and Methods: The Swiss Imatinib COncentration Monitoring Evaluation (I-COME) study was a multicenter randomized controlled trial (ISRCTN31181395). Adult patients in chronic or accelerated phase CML receiving imatinib ≤5 years were eligible. Patients were randomly (1:1) allocated to receive "routine TDM" intervention or to serve as controls with access only to "rescue TDM". All had 1-year follow-up. The primary endpoint was a combined efficacy-safety outcome (failure- and toxicity-free survival without imatinib discontinuation), analyzed in intention-to-treat. Results: Among 56 CML recruited patients, 55 had their molecular and cytogenetic response measured. 14/27 of patients receiving "routine TDM" (52% [33%-71%]) remained event-free versus 16/28 of control patients with "rescue TDM" only (57% [39%-75%]; P=0.69). In the "routine TDM" group, dosage recommendations were adopted entirely in 50% of patients (median Cmin at study end, 895 ng/mL; CV = 33%). These patients had fewer unfavorable events (28% [5%-52%]) compared with patients not receiving the advised dosage (77% [54%-99%]; P = 0.03; median Cmin at study end, 648 ng/mL; CV = 38%). Conclusion: This first prospective target concentration intervention trial could not formally demonstrate a benefit of "routine TDM" of imatinib, especially due to a small patient number and limited prescriber's adherence to dosage recommendations. Nevertheless, the patients receiving the advised dosage more often met target concentrations and the combined outcome (efficacy, tolerance, and persistence). A cycle of routine TDM could thus be favorable, at least in patients eligible for dosage adjustment. Its usefulness should, however, be further confirmed in larger trials

Marrow versus peripheral blood for geno-identical allogeneic stem cell transplantation in acute myelocytic leukemia: Influence of dose and stem cell source shows better outcome with rich marrow

Several studies have compared bone marrow (BM) and peripheral blood (PB) as stem cell sources in patients receiving allografts, but the cell doses infused have not been considered, especially for BM. Using the ALWP/EBMT registry, we retrospectively studied 881 adult patients with acute myelocytic leukemia (AML), who received a non-T-depleted allogeneic BM (n = 515) or mobilized PB (n = 366) standard transplant, in first remission (CR1), from an HLA-identical sibling, over a 5-year period from January 1994. The BM cell dose ranged from 0.17 to 29 × 108/kg with a median of 2.7 × 108/kg. The PB cell dose ranged from 0.02 to 77 × 10 8/kg with a median of 9.3 × 108/kg. The median dose for patients receiving BM (2.7 × 108/kg) gave the greatest discrimination. In multivariate analyses, high-dose BM compared to PB was associated with lower transplant-related mortality (RR = 0.61; 95% CI, 0.39-0.98; P = .04), better leukemia-free survival (RR = 0.65; 95% CI, 0.46-0.91; P = .013), and better overall survival (RR = 0.64; 95% CI, 0.44-0. 92; P = .016). The present study in patients with AML receiving allografts in first remission indicates a better outcome with BM as compared to PB, when the dose of BM infused is rich. © 2003 by The American Society of Hematology

Marrow versus peripheral blood for geno-identical allogeneic stem cell transplantation in acute myelocytic leukemia: Influence of dose and stem cell source shows better outcome with rich marrow

PubMed ID: 12829583Several studies have compared bone marrow (BM) and peripheral blood (PB) as stem cell sources in patients receiving allografts, but the cell doses infused have not been considered, especially for BM. Using the ALWP/EBMT registry, we retrospectively studied 881 adult patients with acute myelocytic leukemia (AML), who received a non-T-depleted allogeneic BM (n = 515) or mobilized PB (n = 366) standard transplant, in first remission (CR1), from an HLA-identical sibling, over a 5-year period from January 1994. The BM cell dose ranged from 0.17 to 29 × 10 8 /kg with a median of 2.7 × 10 8 /kg. The PB cell dose ranged from 0.02 to 77 × 10 8 /kg with a median of 9.3 × 10 8 /kg. The median dose for patients receiving BM (2.7 × 10 8 /kg) gave the greatest discrimination. In multivariate analyses, high-dose BM compared to PB was associated with lower transplant-related mortality (RR = 0.61; 95% CI, 0.39-0.98; P = .04), better leukemia-free survival (RR = 0.65; 95% CI, 0.46-0.91; P = .013), and better overall survival (RR = 0.64; 95% CI, 0.44-0. 92; P = .016). The present study in patients with AML receiving allografts in first remission indicates a better outcome with BM as compared to PB, when the dose of BM infused is rich. © 2003 by The American Society of Hematology