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- Eriksson, Anna, 1977-
(author)
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Studies of New Signal Transduction Modulators in Acute Myeloid Leukemia
- 2012
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Doctoral thesis (other academic/artistic)abstract
- Acute myeloid leukemia (AML) is a life-threatening malignant disorder with dismal prognosis. AML is characterized by frequent genetic changes involving tyrosine kinases, normally acting as important mediators in many basic cellular processes. Due to the overexpression and frequent mutations of the FMS-like receptor tyrosine kinase 3 (FLT3) in AML, this tyrosine kinase receptor has become one of the most sought after targets in AML drug development.In this thesis, we have used a combination of high-throughput screens, direct target interaction assays and sequential cellular screens, including primary patient samples, as an approach to discover new targeted therapies. Gefitinib, a previously known inhibitor of epidermal growth factor receptor and the two novel tyrosine kinase inhibitors AKN-032 and AKN-028, have been identified as compounds with cytotoxic activity in AML.AKN-028 is a potent inhibitor of FLT3 with an IC50 value of 6 nM in an enzyme assay, but also displaying in vitro activity in a variety of primary AML samples, irrespective of FLT3 mutation status or quantitative FLT3 expression. AKN-028 shows a sequence dependent in vitro synergy when combined with standard cytotoxic agents cytarabine or daunorubicin, with better efficacy when cells are exposed to standard chemotherapy simultaneously or for 24 hours prior to adding AKN-028. Antagonism is observed when cells are pre-treated with AKN-028, possibly explained by the cell cycle arrest induced by the compound. In vivo cytotoxic activity and good oral bioavailability have made AKN-028 a candidate drug for clinical studies and the compound is presently investigated in an international two-part multicenter phase I/II study.Results from microarray studies performed to further elucidate the mechanism of action of AKN-028, revealed significantly altered gene expression induced by AKN-028 in both AML cell lines and in primary AML cells, with an enrichment of the Myc pathway among the downregulated genes.Furthermore, tyrosine kinase activity profiling shows a dose-dependent kinase inhibition by AKN-028 in all AML samples tested. Interestingly, cells with a high overall kinase activity were more sensitive to AKN-028. Provided conformation in a larger set of samples, kinase activity profiling may give useful information in individualizing treatment of patients with AML.
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- Flygt, Hjalmar, et al.
(author)
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Long-term tolerability and efficacy after initial PegIFN-α addition to dasatinib in CML-CP : Five-year follow-up of the NordCML007 study
- 2021
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In: European Journal of Haematology. - : John Wiley & Sons. - 0902-4441 .- 1600-0609. ; 107:6, s. 617-623
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Journal article (peer-reviewed)abstract
- ObjectivesTreatment-free remission (TFR) has emerged as a treatment goal in chronic myeloid leukemia in the chronic phase (CML-CP). Attempts to increase proportion of patients achieving TFR include combination of tyrosine kinase inhibitors (TKI) and other drugs. Interferon-α in addition to TKI has shown promising efficacy but with dose-dependent toxicity and discontinuations. NordCML007 was initiated to study the efficacy and safety of low dose pegylated IFN-α (PegIFN-α) in combination with dasatinib (DAS) in CML-CP.MethodsForty patients with newly diagnosed CML-CP were given DAS upfront. After month 3 (M3) 15 μg/wk of PegIFN-α was added and increased to 25 μg/wk from M7 until M15. DAS treatment was continued and adverse events and BCR-ABL1 qRT-PCR values were reported yearly after M24. Results from M1 to M18 have previously been published, and here we present long-term data.ResultsAfter 5 years of follow-up, there were no suspected unexpected serious adverse reactions, no increase in serosal effusions, no disease progressions and no CML-related deaths. Rates of MR3.0 (MMR), MR4.0 and MR4.5 were 84.6%, 64.1% and 51.3% respectively at M60, and 95% of patients reached MMR at some point during the study.ConclusionInitial addition of PegIFN-α to DAS shows good long-term efficacy without increased toxicity.
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- Flygt, Hjalmar, et al.
(author)
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Treatment-free remission after a second TKI discontinuation attempt in patients with Chronic Myeloid Leukemia re-treated with dasatinib - interim results from the DAstop2 trial.
- 2024
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In: Leukemia. - : Springer. - 0887-6924 .- 1476-5551.
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Journal article (peer-reviewed)abstract
- Tyrosine kinase inhibitor (TKI) discontinuation in chronic myeloid leukemia (CML) has become part of routine care for patients with a sustained deep molecular response (DMR). Approximately 50% experience a molecular relapse upon TKI cessation. Most of them quickly regain DMR upon TKI resumption. Whether these patients can achieve a second treatment-free remission (TFR) remains unclear. DAstop2 (ClinicalTrials.gov ID: NCT03573596) is a prospective study including patients with a failed first TFR attempt re-treated with any TKI for ≥ one year. Upon entering the study, patients received the TKI dasatinib for additional two years. Patients with sustained DMR for ≥1 year qualified for a second TKI stop. Ninety-four patients were included between Oct 2017-Dec 2021. At the time of data analysis, 62 patients had attempted a 2nd stop. After a median follow-up of 27 months from 2nd stop, TFR rates were 61, 56 and 46% at 6, 12 and 24 months respectively. No progression to advanced stage disease was seen and 87% had re-achieved MR4 within a median of 3 months from TKI re-initiation. In summary, we show that a 2nd TFR attempt after dasatinib treatment is safe, feasible and TFR rates seem in the range of those reported in trials of a first TKI stop.
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4. |
- Hochhaus, Andreas, et al.
(author)
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Bosutinib for pretreated patients with chronic phase chronic myeloid leukemia : primary results of the phase 4 BYOND study
- 2020
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In: Leukemia. - : Springer Science and Business Media LLC. - 0887-6924 .- 1476-5551. ; 34:8, s. 2125-2137
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Journal article (peer-reviewed)abstract
- Bosutinib is approved for newly diagnosed Philadelphia chromosome-positive (Ph+) chronic phase (CP) chronic myeloid leukemia (CML) and for Ph+ CP, accelerated (AP), or blast (BP) phase CML after prior treatment with tyrosine kinase inhibitors (TKIs). In the ongoing phase 4 BYOND study (NCT02228382), 163 CML patients resistant/intolerant to prior TKIs (n = 156 Ph+ CP CML, n = 4 Ph+ AP CML, n = 3 Ph-negative/BCR-ABL1+ CML) received bosutinib 500 mg once daily (starting dose). As of ≥1 year after last enrolled patient (median treatment duration 23.7 months), 56.4% of Ph+ CP CML patients remained on bosutinib. Primary endpoint of cumulative confirmed major cytogenetic response (MCyR) rate by 1 year was 75.8% in Ph+ CP CML patients after one or two prior TKIs and 62.2% after three prior TKIs. Cumulative complete cytogenetic response (CCyR) and major molecular response (MMR) rates by 1 year were 80.6% and 70.5%, respectively, in Ph+ CP CML patients overall. No patient progressed to AP/BP on treatment. Across all patients, the most common treatment-emergent adverse events were diarrhea (87.7%), nausea (39.9%), and vomiting (32.5%). The majority of patients had confirmed MCyR by 1 year and MMR by 1 year, further supporting bosutinib use for Ph+ CP CML patients resistant/intolerant to prior TKIs.
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5. |
- Thielen, Noortje, et al.
(author)
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Leukemic stem cell quantification in newly diagnosed chronic myeloid leukemia patients predicts response to nilotinib therapy
- 2016
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In: Clinical Cancer Research. - 1078-0432. ; 22:16, s. 4030-4038
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Journal article (peer-reviewed)abstract
- PURPOSE: Leukemic stem cells (LSCs) may harbor important resistance to tyrosine kinase inhibitors in chronic myeloid leukemia (CML). We identified Philadelphia chromosome (Ph) positive CD34+CD38- bone marrow cells (here denoted LSCs) and addressed their response-predictive value in CML patients (n=48) subjected to nilotinib in the ENEST1st trial (NCT01061177).EXPERIMENTAL DESIGN: Two flow cytometry-based cell sorting methods were employed with multiparameter-directed CD45- (MPFC) and BCR-ABL1 probe-linked (FISH) identification of Ph-positive cells, respectively.RESULTS: We observed a positive correlation between the proportion of LSCs at diagnosis and established prognostic markers (blast count, spleen size, Sokal score, hemoglobin). Conversely, a high LSC burden predicted for an inferior molecular response at 3 (MPFC, FISH), 6 (MPFC), 9 (FISH) and 15 months (FISH). During nilotinib therapy, the proportion of LSCs decreased rapidly. At 3 months, a median of only 0.3% LSCs remained among CD34+CD38- cells, and in 33% of the patients the LSC clone was not detectable anymore (FISH). The response kinetics was similar in LSC fractions as it was in the progenitor and unseparated bone marrow cell fractions.CONCLUSION: The proportion of LSCs at diagnosis, as analyzed by two independent methodologies, reflects the biology of the disease and appeared as a prognostic and response-predictive marker in CML patients subjected to first-line nilotinib therapy.
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