Chromosome-positive Chronic Myeloid Leukemia In Chronic Phase Research Articles

Asciminib monotherapy in patients with CML-CP without BCR::ABL1 T315I mutations treated with at least two prior TKIs: 4-year phase 1 safety and efficacy results

Asciminib is approved for patients with Philadelphia chromosome–positive chronic-phase chronic myeloid leukemia (CML-CP) who received ≥2 prior tyrosine kinase inhibitors or have the T315I mutation. We report updated results of a phase 1, open-label, nonrandomized trial (NCT02081378) assessing the safety, tolerability, and antileukemic activity of asciminib monotherapy 10–200 mg once or twice daily in 115 patients with CML-CP without T315I (data cutoff: January 6, 2021). After ≈4-year median exposure, 69.6% of patients remained on asciminib. The most common grade ≥3 adverse events (AEs) included increased pancreatic enzymes (22.6%), thrombocytopenia (13.9%), hypertension (13.0%), and neutropenia (12.2%); all-grade AEs (mostly grade 1/2) included musculoskeletal pain (59.1%), upper respiratory tract infection (41.7%), and fatigue (40.9%). Clinical pancreatitis and arterial occlusive events (AOEs) occurred in 7.0% and 8.7%, respectively. Most AEs occurred during year 1; the subsequent likelihood of new events, including AOEs, was low. By data cutoff, among patients without the indicated response at baseline, 61.3% achieved BCR::ABL1 ≤ 1%, 61.6% achieved ≤0.1% (major molecular response [MMR]), and 33.7% achieved ≤0.01% on the International Scale. MMR was maintained in 48/53 patients who achieved it and 19/20 who were in MMR at screening, supporting the long-term safety and efficacy of asciminib in this population.

The Cytogenetic Landscape of Pediatric Chronic Myeloid Leukemia Diagnosed in Chronic Phase.

Simple SummaryPhiladelphia chromosome-positive chronic myeloid leukemia (CML) is characterized by the translocation of the chromosomes 9 and 22. Additional non-Philadelphia aberrations of chromosomes (nPhAs) and their prognostic relevance for the disease course are comparably well known in adult patients with CML. However, due to the rarity of CML in children and adolescents, nPhAs have hardly been determined systematically in these age groups. Here, we present a large analysis of nPhAs detected in a cohort of 161 patients younger than 18 years who had been diagnosed with CML in chronic phase and enrolled in the German national CML-PAED-II registry. We found a distinct distribution of nPhAs in this pediatric cohort with possible impact on treatment response whereas the survival remained unaffected. Our findings emphasize differences in the disease biology between pediatric and adult patients and prompt further joint international efforts to acquire more data on the disease in this age group.Philadelphia chromosome-positive chronic myeloid leukemia (CML) is cytogenetically characterized by the classic translocation t(9;22)(q34;q11), whereas additional non-Philadelphia aberrations (nPhAs) have been studied extensively in adult patients with CML, knowledge on nPhAs in pediatric patients with CML is still sparse. Here, we have determined nPhAs in a cohort of 161 patients younger than 18 years diagnosed with chronic phase CML and consecutively enrolled in the German national CML-PAED-II registry. In 150 cases (93%), an informative cytogenetic analysis had been performed at diagnosis. In total, 21 individuals (13%) showed nPhAs. Of these, 12 (8%) had a variant translocation, 4 (3%) additional chromosomal aberrations (ACAs) and 5 (3%) harbored a complex karyotype. Chromosome 15 was recurrently involved in variant translocations. No significant impact of the cytogenetic subgroup on the time point of cytogenetic response was observed. Patients with a complex karyotype showed an inferior molecular response compared to patients carrying the classic translocation t(9;22)(q34;q11), variant translocations or ACAs. No significant differences in the probability of progression-free survival and overall survival was found between patients with nPhAs and patients with the classic Philadelphia translocation only. Our results highlight the distinct biology of pediatric CML and underline the need for joint international efforts to acquire more data on the disease pathogenesis in this age group.

Outcomes before and after dose reduction in patients with newly diagnosed chronic myeloid leukemia receiving bosutinib or imatinib.

7039 Background: Bosutinib (BOS) is approved for patients (pts) with Philadelphia chromosome-positive chronic myeloid leukemia (CML), at a starting dose of 400 mg QD in newly diagnosed pts in chronic phase (CP). This analysis evaluated the impact dose reduction has on the outcomes of BOS and imatinib (IMA) in pts with CP CML. Methods: In the open-label BFORE trial, 536 pts with newly diagnosed CP CML were randomized to receive 400 mg QD BOS (N = 268) or IMA (N = 268; 3 untreated). Dose could be reduced to 300 mg QD for toxicity. Following sponsor approval, dose reduction to BOS 200 mg QD was permitted for 4 wks maximum; after this time, dose escalation or treatment discontinuation was required. Maintenance of response after dose reduction was defined as having a response > 6 mo after the first reduction. Database lock: June 12, 2020, 5 y after the last pt enrolled. Results: In the BOS arm, dose reduction to 300 (without further reduction) or 200 mg QD was seen in 82 (31%) and 33 (12%) pts, and median time to dose reduction was 85 and 205 d. In the IMA arm, 50 (19%) pts had a dose reduction to 300 mg QD, and median time to dose reduction was 92 d. Most common (≥2% of pts) treatment-emergent adverse events (TEAEs) leading to dose reduction were increased alanine aminotransferase (8%), thrombocytopenia (7%), diarrhea (7%), increased lipase (6%), increased aspartate aminotransferase (4%), nausea (4%), neutropenia (3%), rash (3%) and abdominal pain (2%) with BOS, and neutropenia (4%) with IMA. Of the pts who remained on 400 mg QD BOS (n = 153) or IMA (n = 214), respectively, 120 (78%) and 139 (65%) achieved major molecular response (MMR). Among pts who had a BOS dose reduction to 300 mg QD, 51/82 (62%) had MMR > 6 mo after dose reduction: 14 (17%) maintained MMR before and after dose reduction and 37 (45%) achieved MMR for the first time after dose reduction. Seven (9%) pts had MMR before dose reduction but discontinued treatment before the next > 6 mo assessment. In the IMA arm, 32/50 (64%) pts had MMR > 6 mo after dose reduction: 9 (18%) maintained MMR before and after dose reduction and 23 (46%) achieved MMR for the first time after dose reduction. One (2%) pt had MMR before dose reduction but discontinued treatment before the next > 6 mo assessment and 1 (2%) pt lost a previously attained MMR after dose reduction. Among pts who had a BOS dose reduction to 200 mg QD, 12/33 (36%) had MMR > 6 mo after dose reduction: 7 (21%) maintained MMR before and after dose reduction and 5 (15%) achieved MMR for the first time after dose reduction. Six (18%) pts had MMR before dose reduction but discontinued treatment before the next > 6 mo assessment. Similar trends were seen for complete cytogenetic response. Conclusions: Management of TEAEs through BOS or IMA dose reduction enabled pts to continue treatment, with a substantial number of pts achieving MMR for the first time after dose reduction. Clinical trial information: NCT02130557.

Maintenance of Health-Related Quality of Life in the Phase 4 BYOND Study of Bosutinib for Pretreated Chronic Phase Chronic Myeloid Leukemia

Maintenance of Health-Related Quality of Life in the Phase 4 BYOND Study of Bosutinib for Pretreated Chronic Phase Chronic Myeloid Leukemia

Long-term patient-reported outcomes from an open-label safety and efficacy study of bosutinib in Philadelphia chromosome-positive chronic myeloid leukemia patients resistant or intolerant to prior therapy.

BACKGROUNDHealth‐related quality of life (HRQOL) in patients with chronic‐phase chronic myeloid leukemia (CML) is important because of the requirement for long‐term treatment. This study assessed HRQOL in bosutinib‐treated patients with Philadelphia chromosome–positive CML and resistance or intolerance to 1 (chronic‐phase second‐line [CP2L]) or more (chronic‐phase third‐line [CP3L]) tyrosine kinase inhibitors who had 264 weeks or more of follow‐up (ClinicalTrials.gov identifier NCT00261846).METHODSPatient‐reported HRQOL was assessed with the EuroQol 5‐Dimensions Questionnaire (EQ‐5D) and the Functional Assessment of Cancer Therapy–Leukemia (FACT‐Leu).RESULTSIn total, 284 and 119 patients composed the CP2L and CP3L cohorts, respectively. At treatment completion, more than 50% of the patients in the CP2L and CP3L cohorts completed the EQ‐5D and FACT‐Leu assessments. The EQ‐5D and EQ‐5D visual analog scale scores were stable in both cohorts throughout treatment. The mean FACT‐Leu scores were generally stable over time but were lower in magnitude in the CP3L cohort versus the CP2L cohort. The FACT‐Leu scale scores of a subset of patients with chronic diarrhea (CP2L, n = 101; CP3L, n = 30) were similar to the scores of the larger cohorts. Minimally important differences (MIDs) from baseline for the FACT‐Leu scale scores were observed for the following: emotional well‐being (EWB), Functional Assessment of Cancer Therapy–General (FACT‐G) Total, FACT‐Leu Total, and Functional Assessment of Cancer Therapy Trial Outcome Index (FACT‐TOI) in the CP2L cohort and FACT‐Leu Total in the CP3L cohort. Among patients with chronic diarrhea, MIDs were observed for EWB, FACT‐G Total, FACT‐Leu Total, and FACT‐TOI in the CP2L cohort and for EWB, FACT‐G Total, and FACT‐Leu Total in the CP3L cohort.CONCLUSIONSHRQOL was maintained with long‐term bosutinib treatment for patients with CP2L and CP3L CML. Cancer 2018;124:587‐95. © 2017 The Authors. Cancer published by Wiley Periodicals, Inc. on behalf of American Cancer Society. This is an open access article under the terms of the Creative Commons Attribution‐NonCommercial License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes.

Cost-Effectiveness of Nilotinib Versus Dasatinib for The Second-Line Treatment of Patients with Philadelphia Chromosome-Positive Chronic Myeloid Leukemia in Chronic Phase (CML-CP), Resistant or Intolerant To Imatinib, in Frame of Russian Healthcare System

Cost-Effectiveness of Nilotinib Versus Dasatinib for The Second-Line Treatment of Patients with Philadelphia Chromosome-Positive Chronic Myeloid Leukemia in Chronic Phase (CML-CP), Resistant or Intolerant To Imatinib, in Frame of Russian Healthcare System

Comparison of Branded and Generic Imatinib Plasma Concentrations in Patients With Chronic Myelogenous Leukemia: Unicentric Study.

For over a decade, imatinib has been the first-line treatment of Philadelphia chromosome-positive chronic myeloid leukemia (CML). Doubts on the bioequivalence and bioavailability of emerging generic compounds have been expressed. Adequate imatinib plasma concentration ([IPC]≥1000 μmol/L) is associated with a better chance of optimal treatment response in patients with CML. In this study, we compared the achieved IPCs between the branded compound and its 2 generic forms. IPCs were compared in 24 consecutive patients with CML in the first chronic phase who changed from branded to generic imatinib. The median age was 49 years (range, 22-76 years). Fifteen of them were male. Six patients were switched to Neopax, 13 to Imakrebin, and 5 patients received both generics consecutively. All compounds were used in an equivalent dose of 400 mg orally once daily for at least 1 month before plasma concentrations were measured. High-performance liquid chromatography was used to determine imatinib plasma concentration from a specimen collected 21 to 24 hours after the last dose. The median IPC achieved with branded imatinib was 1454 μmol/L (range, 485-2707 μmol/L) with 18 patients (75%) having IPC≥ 1000 μmol/L. For Neopax and Imakrebin, median IPCs were 1717 μmol/L (range, 1249-3630 μmol/L) and 1458 μmol/L (range, 707-880 μmol/L), respectively, with 11 of 11 (100%) and 16 of 18 (89%) patients having IPC≥ 1000 μmol/L. No significant difference in measured IPCs between all 3 compounds was found (P > .257). When taken at equivalent doses, imatinib generics are bioequivalent and comparable in clinical efficacy and have the potential for substantial savings in the treatment cost for CML.

Nilotinib.

Targeted therapy of Philadelphia chromosome-positive chronic myeloid leukemia (CML) using the tyrosine kinase inhibitor imatinib mesylate has been one of the most striking achievements in modern cancer medicine. However, while imatinib can establish long-term remission in many cases, resistance to or intolerance of imatinib is eventually experienced by a substantial number of patients. Subsequent advances have led to the development of novel tyrosine kinase inhibitors (TKIs). One such inhibitor, nilotinib, was rationally designed to increase its affinity and specificity for the oncogenic tyrosine kinase Bcr-Abl compared with imatinib and has been shown to be effective after imatinib failure. Recently, nilotinib has been shown to be more effective when used as first-line therapy of chronic phase CML.

Switching patients (pts) with chronic myeloid leukemia in chronic phase (CML-CP) with residual disease on long-term imatinib (IM) to nilotinib (NIL): ENESTcmr 24-mo follow-up.

7053^ Background: The 12-mo results of ENESTcmr demonstrated that switching pts on IM with sustained BCR-ABL positivity to NIL leads to faster, deeper molecular responses (MRs)vs remaining on IM. These deeper molecular responses (MR4.5 [BCR-ABL ≤ 0.0032%IS] or greater) are a prerequisite to enter most treatment-free remission studies. Here, we report 24-mo f/u of ENESTcmr. Methods: Philadelphia chromosome–positive CML-CP pts (N = 207) who achieved a complete cytogenetic response, but had detectable BCR-ABL transcripts after ≥ 2 y on IM, were randomized to receive NIL 400 mg twice daily (BID; n = 104) or continue their IM dose (400/600 mg once daily [QD]; n = 103). Results: By 24 mo, significantly more pts achieved confirmed undetectable BCR-ABL (by RQ-PCR with ≥ 4.5 log sensitivity in 2 consecutive samples) with a switch to NIL vs continuing IM (22.1% vs 8.7%; P = .0087). The increase in the rate of undetectable BCR-ABL from mo 12 to 24 was higher for pts on NIL vs IM (9.6 vs 2.9 percentage points). In pts without MR4.5 at baseline (BL), MR4.5 was achieved by 24 mo in 42.9% vs 20.8% of pts (NIL vs IM; P = .0006). In pts without major molecular response (MMR; ≤ 0.1%IS) at BL, MR4.5 was achieved by 24 mo in 29.2% vs 3.6% of pts (P = .016). No progressions to accelerated phase/blast crisis or deaths occurred on study since the 12-mo f/u. Event-free survival at 24 mo was 96.6% vs 92.8% in the NIL and IM arms, respectively. Discontinuations due to adverse events occurred in 11.5% and 2.9% of pts in the NIL and IM arms. The NIL safety profile was consistent with prior switch studies. Conclusions: By 24 mo, significantly more pts achieved deeper responses (MR4.5and undetectable BCR-ABL) with switch to NIL vs remaining on IM, and the difference between arms in these endpoints increased between 12 and 24 mo. Clinical trial information: NCT00760877. [Table: see text]

Nilotinib in imatinib-resistant or imatinib-intolerant patients with chronic myeloid leukemia in chronic phase: 48-month follow-up results of a phase II study

Nilotinib (Tasigna) is a BCR-ABL1 tyrosine kinase inhibitor approved for the treatment of patients with Philadelphia chromosome-positive chronic myeloid leukemia in chronic phase (CML-CP) who are newly diagnosed or intolerant of or resistant to imatinib. The 48-month follow-up data for patients with CML-CP treated with nilotinib after imatinib resistance or intolerance on an international phase II study were analyzed. Overall, 59% of patients achieved major cytogenetic response; 45% achieved complete cytogenetic response while on study. The estimated rate of overall survival (OS) and progression-free survival (PFS) at 48 months was 78% and 57%, respectively. Deeper levels of molecular responses at 3 and 6 months were highly positively correlated with long-term outcomes, including PFS and OS at 48 months. Of the 321 patients initially enrolled in the study, 98 (31%) were treated for at least 48 months. Discontinuations were primarily due to disease progression (30%) or adverse events (21%). Nilotinib is safe and effective for long-term use in responding patients with CML-CP who are intolerant of or resistant to imatinib. Further significant improvements in therapy are required for patients who are resistant or intolerant to imatinib.

Identifying High Symptom Burden in Patients with Chronic Myeloid Leukemia on Tyrosine Kinase Inhibitor Therapy

Abstract 3138 Background:Patient report of symptom burden from Philadelphia chromosome-positive chronic myeloid leukemia (CML) and its treatment is scarce. Symptom burden is the combined impact of symptoms from disease and treatment on daily functioning. Lack of symptom recognition may result in failure to address symptoms and maximize patient functioning and treatment adherence. The purposes of this study are to develop a valid and reliable patient questionnaire for measuring CML symptom burden and to describe symptom burden over 1 year. This abstract reports intermediate results of the longitudinal symptom burden of CML. Methods:160 patients with CML rated the 20 symptom items (13 core cancer and 7 CML-specific symptom items) and 6 interference items of the M. D. Anderson Symptom Inventory for CML (MDASI-CML), on a 0-to-10 scale (0 = not present or no interference; 10 = as bad as can be imagined or complete interference) every 2 weeks using interactive voice response (IVR) telephone technology. Information on performance status, quality of life, disease history, and treatment was collected at study entry. The longitudinal symptom burden of CML and associated factors are reported using descriptive statistics, t-tests, and group-based trajectory and logistic regression modeling. Results:As of May 31, 2011, 160 patients had completed the MDASI-CML for 6 months; 35 patients (22%) had more that 50% data missing and were excluded from analysis. Of the remaining 125 patients, average age at study entry was 50.7 years (standard deviation [SD] = 13.2), 54% were female, 98% had chronic phase (CP) CML, 94% were receiving tyrosine kinase inhibitor (TKI) therapy, average time on current TKI therapy was 44.2 months (SD = 35.7), 2% began TKI therapy at study entry, and 99% had a clinician-rated ECOG performance status of 1 or less. The 5 most severe symptoms reported by the patients were fatigue (mean = 2.73, SD = 2.38), drowsiness (2.17, 2.26), muscle soreness and cramping (2.09, 2.36), disturbed sleep (2.03, 2.37), and difficulty remembering (1.68, 1.88). Trajectory analysis of a composite of the 5 most severe symptoms showed that patients could be divided into 2 groups reporting significantly more (48 patients, 38%) or less (77 patients, 62%) symptom severity across the 6 months of assessment (Figure 1). Average severity of all the individual symptom and interference items as well as the composite means of the top 5 symptoms, the 13 core symptoms, the 7 CML-specific symptoms, and the 6 interference items were significantly different between the groups (all p<0.01). Multivariate logistic regression modeling showed that being unmarried, higher severity of fatigue, difficulty sleeping, difficulty remembering, lack of appetite, easy bruising and bleeding, and lower severity of diarrhea at the time of study entry were independent factors significantly predicting membership in the high symptom severity group (Table 1). No other demographic or disease and treatment variables significantly predicted group membership. [Display omitted] Implications:A subset of patients (approximately one third) with CML primarily in CP receiving TKI therapy experiences more severe symptoms and needs special attention to symptom management. A single assessment (the MDASI-CML) can identify patients who experience chronically higher symptom burden and who need interventions to ameliorate symptoms, maintain daily functioning, and encourage treatment adherence. More analysis and research is needed to further delineate the symptom burden of CML and its treatment, understand the effects of symptom burden on treatment adherence, and develop effective interventions to relieve more-severe symptoms.TableFactors in CML patients predicting membership in high-symptom severity group.OR*P-Value#Lower CI TFU1-3Upper CI TFU1-3Unmarried13.744.0171.585119.154Fatigue1.616.0021.1842.204Disturbed Sleep1.676.0081.1462.451Difficulty Remembering1.543.0271.0492.268Lack of Appetite2.424.0251.1165.263Diarrhea.594.012.396.890Easy Bruising/Bleeding1.517.0151.0832.124*OR = odds ration;#P-value = probability value;##CI = confidence interval Disclosures:Williams:Novartis: Research Funding. Ault:Novartis: Speakers Bureau; Bristol-Myers Squibb: Speakers Bureau. Cortes:Novartis: Consultancy; Novartis: Research Funding; BMS: Consultancy, Research Funding; Ariad: Consultancy, Research Funding; Pfizer: Consultancy, Research Funding.

Nilotinib is superior to imatinib as first-line therapy of chronic myeloid leukemia: the ENESTnd study

Nilotinib (Tasigna®) is a more potent BCR–ABL inhibitor than imatinib and was designed to overcome imatinib’s deficiencies. Nilotinib has significant efficacy in patients with chronic myeloid leukemia (CML) in chronic phase, accelerated phase and blastic phase, following imatinib failure. Based on the results of the Evaluating Nilotinib Efficacy and Safety in Clinical Trials – Newly Diagnosed Patients (ENESTnd) study, the US FDA has granted accelerated approval of nilotinib for the treatment of adult patients with newly diagnosed Philadelphia chromosome-positive CML in chronic phase. Imatinib has changed our perceptions of the therapeutic power of targeted inhibition of a pathologically active kinase. Nilotinib, a designer agent built on the imatinib scaffold, has proven superior to its template agent by every significant surrogate marker we use in monitoring CML. Nilotinib’s clinical superiority over imatinib, as demonstrated by the ENESTnd study, has established it as an agent that we believe is a significant further step towards the cure of CML.

Imatinib use during pregnancy and breast feeding: a case report and review of the literature

The development of imatinib as a therapeutic agent targeting BCR-ABL has increased the treatment options for chronic myeloid leukemia (CML) by significantly impacting outcomes, and imatinib is recommended by treatment guidelines as the first-line therapy. However, treatment of maternal CML with imatinib during gestation is not recommended because of the potential risk to the fetus. We describe the clinical presentation, course and outcome of one pregnant patient with CML who was treated with imatinib. We review all pregnancies associated with imatinib documented in the literature. A 27-year-old pregnant patient was diagnosed to have Philadelphia chromosome positive chronic phase CML in August 2007. Imatinib was administered (400 mg/day) between the 21st and 39th weeks of gestation. The patient tolerated the drug well and achieved complete hematological and cytogenetic remission. There were no imatinib-related maternal complications during the pregnancy. Fetal growth remained normal as well as amniotic fluid volume estimation. Labor was induced at the 39th gestational week, resulting in the uneventful vaginal delivery of a healthy male infant without any congenital anomaly. Umbilical cord blood and infant peripheral blood were collected at delivery. No postnatal complications occurred; however, imatinib was present in the umbilical cord blood (338 ng/mL) and in the infant's peripheral blood (478 ng/mL). Breast milk was collected on different postpartum days, and concentrations of imatinib were detected. At 10 months of age, the baby had normal growth and development. In light of reported cases and our experience, treatment of CML during the second and third trimesters of gestation and breast feeding seems to be safe, but the data are still limited and the effects of chronic exposure of infants to imatinib are not known. We think that each case should be examined and considered independently, and decisions should be individualized.

Evaluation of the Cepheid GeneXpert BCR-ABL Assay

Patients with chronic myeloid leukemia harbor the chromosomal translocation t(9;22), which corresponds to fusion of the BCR and ABL genes at the DNA level. The translated fusion product is an oncogenic protein with increased ABL tyrosine kinase activity causing cell transformation. To date, reverse transcriptase-polymerase chain reaction is considered the most sensitive method available for detecting low copy numbers of the BCR-ABL gene fusion. Recently, Cepheid introduced its GeneXpert-based assay for the identification of the BCR-ABL gene fusion in cells from blood samples. This system comprises a walk-away self-contained instrument that combines cartridge-based microfluidic sample preparation with reverse transcriptase-polymerase chain reaction-based fluorescent signal detection and BCR-ABL and ABL Ct (threshold cycle) determination. The difference between the BCR-ABL Ct and ABL Ct (DeltaCt) is expected to represent the ratio of the two populations of mRNAs and ultimately the percentage of neoplastic cells present. We tested whether this BCR-ABL fusion detection system could be used as a clinical diagnostic tool for monitoring patients with minimal residual disease of chronic myelogenous leukemia. We report similar performance characteristics, including limit of detection, specificity, sensitivity, and precision, of this automated BCR-ABL fusion detection system to those of a manual TaqMan reverse transcriptase-polymerase chain reaction-based test.

Discontinuation of imatinib therapy after achievement of complete molecular response in a Ph+ CML patient treated while in long lasting complete cytogenetic remission (CCR) induced by interferon

Imatinib has become the gold standard therapy for Ph+ CML, as it induces complete cytogenetic remission (CCR) in 75–90% of patients in chronic phase (CP), and up to 40% of these patients obtain at least a 3 log reduction of BCR/ABL transcript [Kantarjian HM, Cortes JE, O’Brien S, Luthra R, Giles F, Verstovsek S, et al. Long-term survival benefit and improved complete cytogenetic and molecular response rates with imatinib mesylate in Philadelphia chromosome-positive chronic-phase chronic myeloid leukemia after failure of interferon-alpha. Blood. 2004;104:1979–1988]. However, it is not yet stated whether continued therapy is required to maintain this response or whether imatinib may be discontinued after confirmation of a prolonged complete molecular remission (CMR). We here report on a Ph+ CML case in long lasting CCR following interferon-alpha treatment (IFN) which reached CMR with imatinib but soon relapsed at molecular level after this latter drug discontinuation; we considered the present observation also in the light of previously reported data.

Long-term survival benefit and improved complete cytogenetic and molecular response rates with imatinib mesylate in Philadelphia chromosome–positive chronic-phase chronic myeloid leukemia after failure of interferon-α

AbstractWe reviewed 261 patients with chronicphase chronic myelogenous leukemia (CML) after interferon-α (IFN-α) failure treated with imatinib mesylate 400 mg daily. With a median follow-up time of 45 months, the major cytogenetic response rate was 73% and the complete cytogenetic response rate 63%. The estimated 4-year survival rate was 86%. Multivariate analysis for survival identified hematologic resistance to IFN-α (P = .01), splenomegaly (P = .03), and lack of any cytogenetic response after 3 months of therapy (P = .01) to have independent poor prognostic significance. Patients could be divided into good(no adverse factors), intermediate(1 adverse factor), and poor-risk groups (2 or 3 adverse factors; 12% of patients) with estimated 4-year survival rates of 96%, 86%, and 49%, respectively (P < .000 01). The 4-year cumulative major molecular response (quantitative reverse transcriptase–polymerase chain reaction [Q-PCR] = BCR-ABL/ABL less than 0.05%) rate was 43% and complete molecular response rate (BCR-ABL undetectable) 26%. Compared with a historical group of 251 similar patients treated with nonimatinib therapies, imatinib mesylate was associated with a better 4-year survival rate (86% versus 43%; P < .0001); the survival advantage was confirmed by multivariate analysis (hazard ratio, 0.19; P < .0001).

Autologous Hematopoietic Stem Cell Transplantation in Chronic Myeloid Leukemia with Different Clinical Stages

Seven patients with Philadelphia (Ph) chromosome-positive chronic myeloid leukemia (CML) were treated with an ICE-based regimen plus G-CSF with the aim of mobilizing and collecting Ph-negative peripheral stem cells in the setting of an autologous transplant program. Five patients had CML in the first chronic phase and 2 in the accelerated phase. All patients had been previously treated with interferon-α. Median value and ranges for harvested mononuclear cells, CD34+ cells and CFU-GM, respectively: 5.65 × 10⁸/kg (2.61–11.38); 1.48 × 10⁶/kg (0.216–3.5), and 3.43 × 10⁴/kg (0.243–11.6). FISH was the only useful method for detection of minimal residual disease on apheresis product showing <5% t(9;22) positive cells in 2 cases and <10% positive cells in 4 other cases. Four of seven autologous grafts have been transplanted to date. Busulfan conditioning was used in 1 case and TBI/Cy conditioning in 3 other cases. All patients are alive and well following transplantation and are on interferon-α therapy.

Imatinib mesylate: Clinical results in Philadelphia chromosome-positive leukemias

Targeted cancer therapy has long been sought by the oncology community as a potentially better approach than currently available therapies. One targeted therapy that has shown great success is the tyrosine kinase inhibitor imatinib mesylate (formerly STI571, [Gleevec]; Novartis Pharmaceuticals Corp, East Hanover, NJ) which was recently approved for the treatment of Philadelphia chromosome-positive chronic myeloid leukemia (CML). Basic scientific investigation into the molecular causes and pathogenesis of CML and encouraging preclinical investigations on the mechanism of action of imatinib mesylate led to the initiation of phase I clinical trials. Clinical development of imatinib mesylate continued with three large, multicenter, phase II trials. The majority (88%) of interferon-alpha-resistant or intolerant patients in chronicphase CML achieved a complete hematologic response to imatinib mesylate. More importantly, approximately half of patients achieved a major cytogenetic response, a result historically associated with improved survival. Furthermore, 21% of patients in acceleratedphase CML and 13.5% of patients in blastic-phase CML (patient populations with typically poor prognosis before the advent of imatinib mesylate) achieved major cytogenetic responses. Results from ongoing studies will determine the durability of these responses and will evaluate ways to optimize treatment in advancedstage patients using imatinib mesylate in combination with other therapies. Additional trials are planned to investigate the efficacy of imatinib mesylate to treat a variety of solid tumors whose pathogenesis is driven by the other tyrosine kinase targets, c-Kit and platelet-derived growth factor receptor.