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- Jakobsen Falk, Ingrid, et al.
(författare)
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Pharmacogenetic study of the impact of ABCB1 single-nucleotide polymorphisms on lenalidomide treatment outcomes in patients with multiple myeloma: results from a phase IV observational study and subsequent phase II clinical trial
- 2018
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Ingår i: Cancer Chemotherapy and Pharmacology. - : SPRINGER. - 0344-5704 .- 1432-0843. ; 81:1, s. 183-193
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Tidskriftsartikel (refereegranskat)abstract
- Purpose Despite therapeutic advances, patients with multiple myeloma (MM) continue to experience disease relapse and treatment resistance. The gene ABCB1 encodes the drug transporter P-glycoprotein, which confers resistance through drug extrusion across the cell membrane. Lenalidomide (Len) is excreted mainly via the kidneys, and, given the expression of P-gp in the renal tubuli, single-nucleotide polymorphisms (SNPs) in the ABCB1 gene may influence Len plasma concentrations and, subsequently, the outcome of treatment. We, therefore, investigated the influence of ABCB1 genetic variants on Len treatment outcomes and adverse events (AEs). Methods Ninety patients with relapsed or refractory MM, who received the second-line Len plus dexamethasone in the Rev II trial, were genotyped for the ABCB1 SNPs 1199G amp;gt; A (Ser400Asn, rs2229109), 1236C amp;gt; T (silent, rs1128503), 2677G amp;gt; T/A (Ala893Ser, rs2032582), and 3435C amp;gt; T (silent, rs1045642) using pyrosequencing, and correlations to response parameters, outcomes, and AEs were investigated. Results No significant associations were found between genotype and either best response rates or hematological AEs, and 1236C amp;gt; T, 2677G amp;gt; T or 3435C amp;gt; T genotypes had no impact on survival. There was a trend towards increased time to progression (TTP) in patients carrying the 1199A variant, and a significant difference in TTP between genotypes in patients with standard-risk cytogenetics. Conclusions Our findings show a limited influence of ABCB1 genotype on lenalidomide treatment efficacy and safety. The results suggest that 1199G amp;gt; A may be a marker of TTP following Len treatment in standard-risk patients; however, larger studies are needed to validate and clarify the relationship.
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| 2. |
- Lund, Johan, et al.
(författare)
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Lenalidomide versus lenalidomide plus dexamethasone prolonged treatment after second-line lenalidomide plus dexamethasone induction in multiple myeloma
- 2018
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Ingår i: Cancer Medicine. - : WILEY. - 2045-7634. ; 7:6, s. 2256-2268
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Tidskriftsartikel (refereegranskat)abstract
- Lenalidomide (Len) plus dexamethasone (Dex) is approved for the treatment of relapsed or refractory multiple myeloma (RRMM). It is possible that single-agent Len may be effective as prolonged treatment regimen in RRMM once patients demonstrate an initial response to Len+Dex induction. Patients with RRMM who responded to first-line Len+Dex in an observational study (NCT01430546) received up to 24 cycles of either Len (25mg/day) or Len+Dex (25mg/day and 40mg/week) as prolonged treatment in a subsequent phase 2 clinical trial (NCT01450215). In the observational study (N = 133), median time to response was 1.7 (range 0.6-9.6) months. A complete response to all treatments received in both studies was observed in 11% of patients; very good partial response and partial response rates were 31% and 38%, respectively. Corresponding response rates in the subgroup of patients who did not enter the phase 2 trial (n = 71) were 3%, 18%, and 39%, respectively. Rates of disease progression at 2years in the phase 2 trial were 47% versus 31% for Len versus Len+Dex (P = 0.14). After 36months median follow-up in surviving patients, median time to progression was not reached with Len+Dex and was 24.9months (95% confidence interval 12.5-not calculable, P amp;lt; 0.001) with Len. Three-year OS among the total observational study population was 61% (95% CI, 52-69%). The corresponding rate among patients who entered the phase 2 clinical trial was 73% (95% CI, 60-83%) and was significantly lower among those patients who achieved PR but did not proceed into the phase 2 trial (55%; P = 0.01). In the phase 2 trial, OS was 73% in both treatment arms (P = 0.70). Neutropenia and thrombocytopenia were more common with prolonged (phase 2 trial) versus short-term (observational study) Len administration but remained manageable. Prolonged treatment with Len with or without Dex provides sustained, clinically relevant responses and demonstrates an acceptable safety profile.
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