Clinical Outcomes in Patients With COVID-19 and Hematologic Disease

BACKGROUND

Patients with hematologic diseases are at higher risk of the SARS-CoV-2 infection and more severe clinical outcomes of the coronavirus disease. CHRONOS19 is an observational prospective cohort study with the aim to determine the short and longer-term clinical outcomes, risk factors for disease severity and mortality, and rates of postinfectious immunity in patients with malignant and nonmalignant hematologic diseases and COVID-19.

PATIENTS AND METHODS

Overall, 666 patients were enrolled in the study, of which 626 were included in the final data analysis. The primary endpoint was 30-days all-cause mortality. Secondary endpoints included COVID-19 complications, rates of ICU admission and mechanical ventilation, outcomes of a hematologic disease in SARS-CoV-2 infected patients, overall survival, and risk factors for disease severity and mortality. Data from 15 centers were collected at 30, 90, and 180 days after COVID-19 was diagnosed and were managed using a web-based e-data capture platform. All evaluations were performed in the pre-omicron period of COVID-19 pandemic.

RESULTS

Thirty-days all-cause mortality was 18.9%. The predominant cause of death (in 80% of cases) were COVID-19 complications. At 180 days, the majority (70%) of additional deaths were due to hematologic disease progression. At a median follow-up of 5.7 [0.03-19.04] months, 6-months overall survival was 72% [95% CI: 0.69-0.76]. One-third of patients had severe SARS-CoV-2 disease. The rate of ICU admission was 22% with 77% of these patients requiring mechanical ventilation, with poor survival rate. A univariate analysis revealed that older age (≥ 60 years), male sex, malignant hematologic disease, myelotoxic agranulocytosis, transfusion dependence, refractory disease or relapse, diabetes among comorbidities, any complications, especially ARDS alone or in combination with CRS, admission to an ICU, and mechanical ventilation were associated with higher risks of mortality. Treatment of the hematologic disease was changed, postponed, or canceled in 63% of patients. At a longer follow-up (90 and 180 days), the status of the hematologic disease changed in 7.5% of patients.

CONCLUSION

Patients with hematologic disease and COVID-19 have high mortality rates, predominantly due to COVID-19 complications. At a longer-term follow-up, no significant impact of COVID-19 on the course of a hematologic disease was revealed.

Withdrawal syndrome after tyrosine kinase inhibitors discontinuation in patients with chronic myeloid leukemia

Background. Withdrawal syndrome (WS) a musculoskeletal pain after discontinuation of tyrosine kinase inhibitors (TKI) in patients with chronic myeloid leukemia (CML) has been described in the treatment-free remission (TFR) studies. The pathophysiological mechanisms and predisposing factors of WS have not been well established. Aim. Our aim was to evaluate clinical features and factors associated with WS in the Russian cohort of CML patients who discontinued TKI therapy. Materials and methods. WS was evaluated in total of 183 CML patients with chronic phase and sustained deep molecular response (DMR). WS was defined as a musculoskeletal pain newly observed after TKI cessation or as a worsening of previously observed symptoms. Results. DMR loss free survival at 36 months was 49% and 43% in prospective and retrospective groups respectively (p=0.96) with mеdian (Me) time of observation 33 months (range 1136). WS was observed in 49 (27%) patients: grade 12 was in 45 (92%) patients, grade 3 in 4 (8%) patients. Me time to WS occurrence was 2 months (range 17), Ме duration of WS was 5 months (range 135). WS was resolved in 14 of 15 patients with molecular relapse after 13 months of TKI re-initiation and was decreased in 1 patient. WS was completely resolved in 31 of 34 patients who continued remained in TFR and decreased in 3 patients. WS was resolved spontaneously or with nonsteroidal anti-inflammatory drugs in 14 (45%) and 17 (55%) patients accordingly. Older age (p0.0001), longer duration of TKI therapy (p0.0001) and presence of locomotion system diseases (p=0.022) were observed in patients with WS. No WS was observed in pregnant patients (р0.001). Survival without DMR loss at 12 months after TKI stop was 66 and 42% in patients with and without WS accordingly (р=0.095). Conclusion. The rate of WS was 27% that is in a good concordance with the data of the other TFR studies. A longer period of TKI exposure, older age and the history of locomotion system diseases were associated with the development of the WS. We found for the first time that WS was not observed in patients with pregnancy. There was no association of WS development and the rate of molecular relapses.

Efficacy and safety results from ASCEMBL, a phase 3 study of asciminib versus bosutinib (BOS) in patients (pts) with chronic myeloid leukemia in chronic phase (CML-CP) after ≥2 prior tyrosine kinase inhibitors (TKIs): Week 96 update

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Background: Asciminib is the first BCR::ABL1 inhibitor to specifically target the ABL Myristoyl Pocket (STAMP). In the ASCEMBL primary analysis, asciminib had superior efficacy and better safety/tolerability than BOS in pts with CML-CP after ≥2 prior TKIs. After a median follow-up of 2.3 years (16.5 months’ additional follow-up since primary analysis), we report efficacy and safety results (cutoff: October 6, 2021). Methods: Eligible pts were adults with CML-CP after ≥2 prior TKIs, with intolerance or lack of efficacy per 2013 European LeukemiaNet. Pts were randomized 2:1 to asciminib 40 mg twice daily or BOS 500 mg once daily, stratified by major cytogenetic response (MCyR) status (Ph+ metaphases ≤35%) at baseline. The key secondary endpoint was major molecular response (MMR) rate at wk 96. Results: 233 pts were randomized to asciminib (n=157) or BOS (n=76). At cutoff, treatment was ongoing in 84 (53.5%) and 15 (19.7%) pts, respectively; the most common reason for discontinuation was lack of efficacy in 38 (24.2%) and 27 (35.5%) pts, respectively. MMR rate at wk 96 (per ITT) was higher on asciminib (37.6%) than BOS (15.8%). The difference, adjusting for baseline MCyR, was 21.7% (95% CI, 10.5%-33.0%; 2-sided P=.001). More pts on asciminib than BOS, respectively, had BCR::ABL1IS ≤1% (45.1% vs 19.4%) at wk 96. The probability of maintaining MMR and BCR::ABL1IS ≤1% for ≥72 wk was 96.7% (95% CI, 87.4%-99.2%) and 94.6% (95% CI, 86.2%-97.9%), respectively, on asciminib and 92.9% (95% CI, 59.1%-99.0%) and 95.0% (95% CI, 69.5%-99.3%), respectively, on BOS. Median duration of exposure was 103.1 (range, 0.1-201.1) wk on asciminib and 30.5 (range, 1.0-188.3) wk on BOS. Despite the longer duration of asciminib exposure, safety/tolerability of asciminib continued to be better than that of BOS (Table). No new on-treatment deaths were reported since the primary analysis. Most frequent (>10%) grade ≥3 adverse events (AEs) on asciminib vs BOS were thrombocytopenia (22.4%, 9.2%), neutropenia (18.6%, 14.5%), diarrhea (0%, 10.5%), and increased alanine aminotransferase (0.6%, 14.5%). Conclusions: After >2 years of follow-up, asciminib continued to show superior efficacy and better safety/tolerability vs BOS. Responses were durable, with more pts on asciminib in MMR. Additionally, more pts on asciminib had BCR::ABL1IS ≤1%, a milestone response in later lines associated with improved survival. These results continue to support the use of asciminib as a new CML therapy, with the potential to transform standard of care. Clinical trial information: NCT03106779. [Table: see text]

Second-line bosutinib (BOS) for patients (pts) with chronic phase (CP) chronic myeloid leukemia (CML): Final 10-year results of a phase 1/2 study

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Background: BOS is approved for Philadelphia chromosome (Ph)+ CML resistant/intolerant to prior therapy and newly diagnosed Ph+ CP CML. In a phase 1/2 study, second-line BOS showed durable efficacy and manageable toxicity in pts with imatinib-resistant (IM-R) or -intolerant (IM-I) Ph+ CP CML. Methods: This final efficacy and safety analysis of the phase 1/2 study and extension study was based on ≥10 y of follow-up (FU). Ph+ CP CML pts who received BOS starting at 500 mg/d after prior treatment (Tx) with imatinib only were included. Results: 19% of pts were on BOS at y 10, and 13% were still on BOS at study completion after ≥10 y; 19% completed ≥10 y of FU. Median duration of Tx and FU were 26 and 54 mo, respectively. Median (range) dose intensity was 436 (87–599) mg/d. The most common primary reasons for permanent Tx discontinuation were lack of efficacy (unsatisfactory response or disease progression; 27%) and adverse events (AEs; 26%). In pts with a valid baseline assessment, cumulative complete cytogenetic response (CCyR), major molecular response (MMR) and MR4 rates (95% CI), respectively, were 50% (43–56), 42% (35–49) and 37% (30–44) (IM-R: 48% [41–56], 46% [37–55] and 39% [31–48]; IM-I: 53% [41–64], 36% [25–48] and 33% [22–45]). Responses were durable, with estimated probabilities of maintaining CCyR, MMR and MR4 > 50% after ≥10 y (Table). At 10 y, cumulative incidence of on-Tx progression/death was 24% and Kaplan-Meier (K-M) overall survival 72% (Table); 55 deaths (IM-R: n = 41; IM-I: n = 14) occurred on study, none BOS-related. Any grade Tx-emergent AEs (TEAEs) in ≥40% of pts were diarrhea (86%), nausea (46%) and thrombocytopenia (42%). Pleural effusion, cardiac and vascular TEAEs occurred in 13%, 12% and 11% of pts, respectively. 28% of pts had AEs leading to permanent Tx discontinuation; most common (≥2% of pts) were thrombocytopenia (6%), neutropenia (2%) and alanine aminotransferase increased (2%). Conclusions: These 10-y data are consistent with prior results of durable efficacy and manageable toxicity with second-line BOS and support long-term BOS use in CP CML pts after imatinib failure. Clinical trial information: NCT00261846 and NCT01903733. [Table: see text]

[Successful use of long-term follow-up in patients with chronic myeloid leukemia with a deep molecular response at reduced doses of 2nd generation tyrosine kinase inhibitors: clinical cases and literature review]

Therapy with tyrosine kinase inhibitors (TKI) allows to achieve a deep molecular response in 6070% of patients with chronic myeloid leukemia (CML). According to the current guidelines CML patients receive a long-term treatment with TKI in standard dose. The frequently observed adverse effects (AE) of TKI therapy are mostly dose-dependent. A new treatment approach with TKI use in reduced dose is desirable for the CML patients with existing AE or with a high risk of AE occurrence. We report the two cases of successful long-term treatment of CML patients with reduced doses of second generation TKIs. The aim of the TKI dose reduction was to reduce the clinical manifestations of drug toxicities and to prevent the AE.

Analysis of the Mortality of Russian Patients With Chronic Myeloid Leukemia in the Multicenter EUTOS ELN Population-based Study (EUTOS-PBS)

INTRODUCTION

Russia took part in the multicenter population-based study (Europe) and included 6.8% adult patients with newly diagnosed chronic myeloid leukemia (CML). The objective of this study was to analyze the mortality in the Russian cohort of patients with newly diagnosed CML in the EUTOS PBS observational study.

PATIENTS AND METHODS

The analyzed cohort consisted of 197 patients (>18 years) with Ph+/BCR-ABL1+ CML diagnosed in the period from October 1, 2009 through December 31, 2012 from 6 regions of Russia. The distribution of the phases of CML were: chronic phase (CP), 93.4% and accelerated phase (AP) + blast crisis (BC), 6% + 0.6%. The median age was 50 years (range, 18-82 years); the male/female ratio was equal.

RESULTS

The overall survival (OS) at 5, 6, and 7 years was 80% (95% confidence interval [CI], 72%-86%), 78% (95% CI, 65%-80%), and 73% (95% CI, 65%-80%), respectively (P < .001). The 5-year OS in patients with AP and BC was 39%. In Russia, the study was prolonged, with a median follow-up of 77 months (range, 0.7-108 months): 141 (71.5%) patients were alive, 47 (24%) patients died, and the status of 9 (4.5%) patients is was unknown. Forty-seven (23.8%) patients died during the follow-up period. The largest number of deaths was observed in the first year after the CML diagnosis: 17 (36%) of 47 cases, 3 of 17 died refusing the CML treatment. At the seventh year of CML therapy, 1 patient died after allogenic hematopoietic stem cell transplantation. The causes of death were: (1) progression of CML to AP/BC in 20 (43%) patients; (2) death in remission in 5 (11%) patients with complete cytogenetic response (CCyR) and/or major molecular response; and (3) death without progression to AP/BC but with signs of leukemia in 22 (46%) patients. The 5-year cumulative incidence of death from all reasons was 20%; the cumulative incidence of CML-related and non-CML-related death at the fifth year was 18% and 11%, respectively.

CONCLUSION

In general, the results of treatment in the Russian population sample of non-selected patients with CML were comparable with the data of the total European cohort. The CML-related deaths prevailed in the first year of CML therapy. The appropriate monitoring and therapy interventions during the first year of CML treatment are apparently important for the long-term treatment results.

Multipotent Mesenchymal Stromal Cells in Patients with Chronic Myeloid Leukemia before Discontinuation of Tyrosine Kinase Inhibitors

We analyzed changes in multipotent mesenchymal stromal cells of patients with chronic myeloid leukemia before discontinuation of tyrosine kinase inhibitors. Withdrawal syndrome was significantly more common in patients who have been taking tyrosine kinase inhibitors for a longer time and in patients of older age and with lower body weight. In patients with withdrawal syndrome, the total production of mesenchymal stromal cells and expression of FGFR2 and MMP2 genes were significantly lower; loss of deep molecular response was also less frequent in this group of patients. At the same time, the expression of genes important for the maintenance of stem cells (SOX9, PDGFRa, and LIF) was significantly lower in the mesenchymal stromal cells of patients with withdrawal syndrome and loss of deep molecular response. We observed a clear-cut relationship between the development of withdrawal syndrome and the loss of deep molecular response. The decrease in the expression of FGFR2 and MMP2 genes in the mesenchymal stromal cells of patients with chronic myeloid leukemia before discontinuation of treatment can be a predictor of withdrawal syndrome, while simultaneous decrease in the expression of SOX9, PDGFRa, and LIF in these cells attests to undesirability of therapy discontinuation at the moment.

ENESTop 192-week results: Treatment-free remission (TFR) in patients (pts) with chronic myeloid leukemia in chronic phase (CML-CP) after stopping second-line (2L) nilotinib (NIL)

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Background: In the ENESTop study (NCT01698905) of TFR in pts with CML-CP who achieved a sustained deep molecular response (MR) with 2L NIL, 57.9% remained in TFR 48 wks after stopping NIL (primary endpoint). Analyses at 144 wks showed durability of TFR. Data from longer follow-up (192 wks) evaluating the maintenance of TFR are reported. Methods: Pts treated with ≥2 y NIL after > 4 wks imatinib (≥3 y total) and achieving MR4.5 ( BCR-ABL1IS ≤0.0032%) on NIL were eligible. After a 1 y consolidation, pts with no confirmed loss of MR4.5 could attempt TFR. NIL was resumed upon loss of major MR ( BCR-ABL1IS ≤0.1%) or confirmed loss of MR4 ( BCR-ABL1IS ≤0.01%). At the data cut-off (Sep 24 2018), all pts had completed ≥192 wks of TFR, resumed NIL, or discontinued the study. Results: By the data cut-off, of 126 pts entering TFR, 56 were ongoing, 59 had resumed NIL, and 11 had discontinued. TFR rate at 192 wks was 46.0% (58/126; 95% CI, 37.1–55.1%); all but 1 of the 58 pts were in MR4.5. Only 1/61 pts in TFR at 144 wks lost response by 192 wks (confirmed loss of MR4); another 2 pts discontinued due to serious AE (polycythemia vera) and pt/guardian decision, respectively. Of 59 pts who resumed NIL, 56 (94.9%) and 55 (93.2%) regained MR4 and MR4.5, respectively. 40/56 pts (71.4%) who regained MR4 had stable MR4 at 96 wks (12 discontinued < 96 wks, and 4 remained on study with < 96 wks, after regaining MR4); 37/55 pts (67.3%) who regained MR4.5 had stable MR4.5 at 96 wks (12 discontinued < 96 wks, and 6 remained on study with < 96 wks, after regaining MR4.5). There were no disease progressions, deaths due to CML, or new deaths since the 144-wk analysis. The 192 wk treatment-free survival rate was 50.3% (95% CI, 41.2–58.7%). Of 62 pts who remained in TFR for > 144 wks, 11.3%, 53.2%, 21.0%, 14.5% and 3.2% had musculoskeletal pain AEs during consolidation and each subsequent 48 wk period of TFR. Among 59 pts who resumed NIL, most common AEs were hypertension (20.3%) and arthralgia (13.6%); the majority of AEs were grade 1/2. Conclusions: Results demonstrate long-term durability and safety of TFR following 2L NIL, with no disease progressions or CML-related deaths, and musculoskeletal pain AEs were transient. Clinical trial information: NCT01698905.

Exome, transcriptome and miRNA analysis don't reveal any molecular markers of TKI efficacy in primary CML patients

BACKGROUND

Approximately 5-20% of chronic myeloid leukemia (CML) patients demonstrate primary resistance or intolerance to imatinib. None of the existing predictive scores gives a good prognosis of TKI efficacy. Gene polymorphisms, expression and microRNAs are known to be involved in the pathogenesis of TKI resistance in CML. The aim of our study is to find new molecular markers of TKI therapy efficacy in CML patients.

METHODS

Newly diagnosed patients with Ph+ CML in chronic phase were included in this study. Optimal and non-optimal responses to TKI were estimated according to ELN 2013 recommendation. We performed genotyping of selected polymorphisms in 62 blood samples of CML patients, expression profiling of 33 RNA samples extracted from blood and miRNA profiling of 800 miRNA in 12 blood samples of CML patients.

RESULTS

The frequencies of genotypes at the studied loci did not differ between groups of patients with an optimal and non-optimal response to TKI therapy. Analysis of the expression of 34,681 genes revealed 26 differently expressed genes (p < 0.05) in groups of patients with different TKI responses, but differences were very small and were not confirmed by qPCR. Finally, we did not find difference in miRNA expression between the groups.

CONCLUSIONS

Using modern high-throughput methods such as whole-exome sequencing, transcriptome and miRNA analysis, we could not find reliable molecular markers for early prediction of TKI efficiency in Ph+ CML patients.

Treatment-Free Remission After Second-Line Nilotinib Treatment in Patients With Chronic Myeloid Leukemia in Chronic Phase: Results From a Single-Group, Phase 2, Open-Label Study

BACKGROUND

Treatment-free remission (TFR)-that is, stopping tyrosine kinase inhibitor (TKI) therapy without loss of response-is an emerging treatment goal in chronic myeloid leukemia (CML).

OBJECTIVE

To evaluate TFR after discontinuation of second-line nilotinib therapy.

DESIGN

Single-group, phase 2, open-label study. (ClinicalTrials.gov: NCT01698905).

SETTING

63 centers in 18 countries.

PATIENTS

Adults with CML in chronic phase who received TKI therapy for at least 3 years (>4 weeks with imatinib, then ≥2 years with nilotinib) and achieved MR4.5 (BCR-ABL1 ≤0.0032% on the International Scale [BCR-ABL1IS]) while receiving nilotinib entered a 1-year consolidation phase. Those with sustained MR4.5 during consolidation were eligible to enter TFR.

INTERVENTIONS

Patients received nilotinib during consolidation; those who entered TFR stopped treatment. Patients with loss of major molecular response (MMR) (BCR-ABL1IS ≤0.1%) or confirmed loss of MR4 (BCR-ABL1IS ≤0.01%) during TFR reinitiated nilotinib treatment.

MEASUREMENTS

Proportion of patients without loss of MMR, confirmed loss of MR4, or treatment reinitiation within 48 weeks of stopping treatment (primary end point).

RESULTS

163 patients who had switched from imatinib to nilotinib (for reasons including resistance, intolerance, and physician preference) enrolled in the study and entered the consolidation phase. Of these patients, 126 met the criteria for entering the TFR phase, and 73 (58% [95% CI, 49% to 67%]) and 67 (53% [CI, 44% to 62%]) maintained TFR at 48 weeks (primary end point) and 96 weeks, respectively. Of the 56 patients who reinitiated nilotinib therapy, 55 regained MMR or better and 52 regained MR4.5. None had CML progression to accelerated phase or blast crisis. Musculoskeletal pain was more frequent during the first 48 weeks after nilotinib discontinuation.

LIMITATION

The study included a heterogeneous patient population and was not designed to compare outcomes between patients continuing and those stopping treatment.

CONCLUSION

TFR seems achievable in patients with sustained MR4.5 after switching to nilotinib.

PRIMARY FUNDING SOURCE

Novartis Pharmaceuticals Corporation.

[Results of following up patients with chronic myeloid leukemia and a deep molecular response without tyrosine kinase inhibitor therapy]

AIM

To assess the results of following up patients with chronic myeloid leukemia (CML) and a deep molecular response (MR) without tyrosine kinase inhibitor (TKI) therapy.

SUBJECTS AND METHODS

The reasons for TKI discontinuation in 70 patients with CML and a deep MR of more than 1 year's duration were adverse events, pregnancy, and patients' decision. Information was collected retrospectively and prospectively in 2008-2016.

RESULTS

The median follow-up after TKI therapy discontinuation was 23 months (2 to 100 months). At 6, 12 and 24 months after TKI therapy discontinuation, the cumulative incidence of major MR (MMR) loss was 28, 41 and 48%, respectively; the survival rates without TKI therapy were 69, 50, and 39%, respectively. MMR loss was noted in 28 (88%) patients at 12 months; it was not seen without TKI therapy at 2-year follow-up. Deaths due to CML progression were absent. The Sokal risk group was a reliable factor influencing MMR loss (p ≤ 0.05). The cumulative recovery rate for deep MR after resumption of TKI use was 73 and 100% at 12 and 24 months, respectively, with a median follow-up of 24 months (1 to 116 months). Deep MR recovered at a later time when the therapy was resumed more than 30 days after MMR loss.

CONCLUSION

Safe follow-up is possible in about 50% of the patients with CML and stable deep MRs without TKI therapy. The introduction of this approach into clinical practice requires regular molecular genetic monitoring and organizational activities. Biological factors in maintaining remission after TKI discontinuation need to be separately studied.

Nilotinib dose-optimization in newly diagnosed chronic myeloid leukaemia in chronic phase: final results from ENESTxtnd

The Evaluating Nilotinib Efficacy and Safety in Clinical Trials-Extending Molecular Responses (ENESTxtnd) study was conducted to evaluate the kinetics of molecular response to nilotinib in patients with newly diagnosed chronic myeloid leukaemia in chronic phase and the impact of novel dose-optimization strategies on patient outcomes. The ENESTxtnd protocol allowed nilotinib dose escalation (from 300 to 400 mg twice daily) in the case of suboptimal response or treatment failure as well as dose re-escalation for patients with nilotinib dose reductions due to adverse events. Among 421 patients enrolled in ENESTxtnd, 70·8% (95% confidence interval, 66·2-75·1%) achieved major molecular response (BCR-ABL1 ≤ 0·1% on the International Scale) by 12 months (primary endpoint). By 24 months, 81·0% of patients achieved major molecular response, including 63·6% (56 of 88) of those with dose escalations for lack of efficacy and 74·3% (55 of 74) of those with dose reductions due to adverse events (including 43 of 54 patients with successful re-escalation). The safety profile of nilotinib was consistent with prior studies. The most common non-haematological adverse events were headache, rash, and nausea; cardiovascular events were reported in 4·5% of patients (grade 3/4, 3·1%). The study was registered at clinicaltrials.gov (NCT01254188).

[Efficiency of interferon therapy in patients with essential thrombocythemia or polycythemia vera]

AIM

To evaluate the efficiency of interferon (IFN) therapy in patients with essential thrombocythemia (ET) and polycythemia vera (PV).

SUBJECTS AND METHODS

A total of 61 patients (41 with ET and 20 with PV) were examined. Prior to study enrolment, 44 (72%) patients with ET or PV received one or other therapy (aspirin was not taken into account). The mean Jak2V617F mutant allele at baseline was 23% (6-54%) in the patients with ET and 40% (11-88%) in those with PV. The median time from diagnosis to enrollment was 49 months.

RESULTS

The paper presents the clinical and molecular findings of long-term INF-α therapy in patients with ET or PV. The median follow-up was 52 months. Recombinant IFN-α2 showed its ability to induce complete hematologic remission (ET (76%), PV (70%)) and a complete molecular response. 22 (69%) out of 32 patients were noted to have a smaller number of cells with the Jak2V617F mutation. In the patients with PV and in those with ET, the relative reduction in the proportion of cells with the Jak2V617F mutant gene averaged 85% and 56% of the baseline values, respectively. There was a reduction in the proportion of cells expressing the Jak2V617F mutation in both the ET (from 12 to 2.2%; p=0.001) and PV (from 32.7% to 3.2%) groups (р=0.001). Ten (31%) patients achieved a deep molecular remission (≤2% Jak2V617F allele); among them, 5 patients were not found to have Jak2V617F mutation. The obtained molecular response remained in 7 of the 10 patients untreated for 11 to 86 months. The long-term treatment with IFN-α led to normalization of the morphological pattern of bone marrow in 5 of the 7 PV or ET patients.

CONCLUSION

Significant molecular remissions achieved by therapy with recombinant interferon-α2 confirm the appropriateness of this treatment option in in the majority of patients with ET or PV.

[A rare case of myeloproliferative disease with t(8;13)(p11;q12) associated with eosinophilia and lymphadenopathy]

Myeloproliferative disease associated with FGFR1 rearrangement (8p11), which is included in the 2008 WHO Classification of Myeloid Neoplasms, is a rare and extremely aggressive abnormality. The paper describes a clinical case of a 39-year-old female patient who was detected to have leukocytosis (as high as 47.2·109/l), absolute eosinophilia (as high as 3.1·109/l), and enlarged peripheral lymph nodes during her visit to a doctor. The bone marrow (BM) showed the changes typically encountered in myeloproliferative disease with eosinophilia. The patient was found to have t(8;13)(p11;q12) translocation associated with the rearrangement of the FGFR1 gene located at the 8p11 locus. Molecular and cytogenetic examinations failed to reveal BCR-ABL chimeric transcript, Jak2 V617F mutation, and deletions and translocations involving PDGFRA (4q12) and PDGFRB (5q32-33). The similar changes in the karyotype were also found in the lymph node cells. The undertaken treatment with hydroxyurea and the tyrosine kinase inhibitor dasatinib turned out to be ineffective. The patient underwent allogeneic BM transplantation from a HLA-identical sibling. Graft rejection occurred 6 months later. Allogeneic BM transplantation from the same donor (100% donor chimerism; FGFR1/8р11 translocation was not detected), which was complicated by the development of chronic graft-versus-host reaction, was performed again in March 2015. The patient is being followed up and continues to receive immunosuppressive therapy.

Frequent variations in cancer-related genes may play prognostic role in treatment of patients with chronic myeloid leukemia

BACKGROUND

Genome variability of host genome and cancer cells play critical role in diversity of response to existing therapies and overall success in treating oncological diseases. In chronic myeloid leukemia targeted therapy with tyrosine kinase inhibitors demonstrates high efficacy in most of the patients. However about 15 % of patients demonstrate primary resistance to standard therapy. Whole exome sequencing is a good tool for unbiased search of genetic variations important for prognosis of survival and therapy efficacy in many cancers. We apply this approach to CML patients with optimal response and failure of tyrosine kinase therapy.

RESULTS

We analyzed exome variations between optimal responders and failures and found 7 variants in cancer-related genes with different genotypes in two groups of patients. Five of them were found in optimal responders: rs11579366, rs1990236, rs176037, rs10653661, rs3803264 and two in failures: rs3099950, rs9471966. These variants were found in genes associated with cancers (ANKRD35, DNAH9, MAGEC1, TOX3) or participating in cancer-related signaling pathways (THSD1, MORN2, PTCRA).

CONCLUSION

We found gene variants which may become early predictors of the therapy outcome and allow development of new early prognostic tests for estimation of therapy efficacy in CML patients. Normal genetic variation may influence therapy efficacy during targeted treatment of cancers.

Long-term efficacy and safety of bosutinib in patients with advanced leukemia following resistance/intolerance to imatinib and other tyrosine kinase inhibitors

Long-term efficacy and safety of bosutinib (≥4 years follow-up from last enrolled patient) were evaluated in an ongoing phase 1/2 study in the advanced leukemia cohort with prior treatment failure (accelerated-phase [AP, n = 79] chronic myeloid leukemia [CML], blast-phase [BP, n = 64] CML, acute lymphoblastic leukemia [ALL, n = 24]). Fourteen AP, 2 BP, and 1 ALL patient remained on bosutinib at 4 years (vs. 38, 8, 1 at 1 year); median (range) treatment durations: 10.2 (0.1-88.6), 2.8 (0.03-55.9), 0.97 (0.3-89.2) months. Among AP and BP patients, 57% and 28% newly attained or maintained baseline overall hematologic response (OHR); 40% and 37% attained/maintained major cytogenetic response (MCyR) by 4 years (most by 12 months). In responders at 1 versus 4 years, Kaplan-Meier (KM) probabilities of maintaining OHR were 78% versus 49% (AP) and 28% versus 19% (BP); KM probabilities of maintaining MCyR were 65% versus 49% (AP) and 21% versus 21% (BP). Most common AEs (AP, BP) were gastrointestinal (96%; 83%), primarily diarrhea (85%; 64%), which was typically low grade (maximum grade 1/2: 81%; 59%) and transient; no patient discontinued due to diarrhea. Serious AEs occurred in 44 (56%) AP and 37 (58%) BP patients, most commonly pneumonia (n = 9) for AP and pyrexia (n = 6) for BP; 11 and 13 died within 30 days of last dose (2 considered bosutinib-related [AP] per investigator). Responses were durable in ∼50% AP responders at 4 years (∼25% BP patients responded at year 1, suggesting possible bridge-to-transplant role in BP patients); toxicity was manageable.

[FIP1L1-PDGFRА-positive myeloproliferative disease with eosinophilia: A rare case with multiple organ dysfunction and a response to tyrosine kinase inhibitor therapy]

The described case of FIP1L1-PDGFRА-positive myeloproliferative disease is characterized by an atypical aggressive course to develop severe specific complications as injuries to the brain, heart, lung, and intestine. Pathogenetic therapy with imatinib could stabilize a patient's state, but failed to produce a complete hematological response. Switching from imatinib to dasatinib could produce sustained clinical, hematological, and molecular remissions.

Bosutinib efficacy and safety in chronic phase chronic myeloid leukemia after imatinib resistance or intolerance: Minimum 24-month follow-up

Bosutinib is an orally active, dual Src/Abl tyrosine kinase inhibitor for treatment of chronic myeloid leukemia (CML) following resistance/intolerance to prior therapy. Here, we report the data from the 2-year follow-up of a phase 1/2 open-label study evaluating the efficacy and safety of bosutinib as second-line therapy in 288 patients with chronic phase CML resistant (n = 200) or intolerant (n = 88) to imatinib. The cumulative response rates to bosutinib were as follows: 85% achieved/maintained complete hematologic response, 59% achieved/maintained major cytogenetic response (including 48% with complete cytogenetic response), and 35% achieved major molecular response. Responses were durable, with 2-year estimates of retaining response >70%. Two-year probabilities of progression-free survival and overall survival were 81% and 91%, respectively. The most common toxicities were primarily gastrointestinal adverse events (diarrhea [84%], nausea [45%], vomiting [37%]), which were primarily mild to moderate, typically transient, and first occurred early during treatment. Thrombocytopenia was the most common grade 3/4 hematologic laboratory abnormality (24%). Outcomes were generally similar among imatinib-resistant and imatinib-intolerant patients and did not differ with age. The longer-term results of the present analysis confirm that bosutinib is an effective and tolerable second-line therapy for patients with imatinib-resistant or imatinib-intolerant chronic phase CML. http://ClinicalTrials.gov Identifier: NCT00261846. Am. J. Hematol. 89:732–742, 2014. © 2014 The Authors American Journal of Hematology Published by Wiley Periodicals, Inc.

[Incidence of chronic myeloid leukemia in 6 regions of Russia according to the data of the 2009-2012 population-based study]

AIM

To assess the main epidemiological characteristics of chronic myeloid leukemia (CML) in the Russian Federation.

SUBJECTS AND METHODS

A planned epidemiological prospective study was conducted in 2009-2012 in 6 Russian regions with the total number of 10.1 million inhabitants, which notified all new CML cases.

RESULTS

The unstandardized (unnormalized, baseline) recorded incidence of CML in the examined regions was 0.58 per 100,000 annually. Its standardized (normalized) incidence was 0.70 for the WHO standard population and 0.72 for the European standard population. The regional variations in the incidence were 0.44 to 0.69. The structural analysis of the incidence in the age strata indicated that the overall morbidity was less due to the decreased rate of registration in old age groups. The morbidity rates in patients aged less than 60 years were nearly similar to the European rates; those in patients aged over 70 years were almost 10 times lower. The lower rate of detection and screening diagnosis of CML in pensioners in primary health care is discussed.

CONCLUSION

The data obtained in this study may serve as the starting point for monitoring the CML epidemiological situation.

[Synchronous and metachronous myeloid and lymphoid tumors]

AIM

To determine the clinical features of multiple primary tumors (MPT) in patients with hemoblastoses, to develop treatment policy for synchronous and metachronous tumors, and to determine the impact of chemotherapy for one disease on the course and prognosis of another one.

SUBJECTS AND METHODS

The investigation included 20 patients with multiple primary synchronous and metachronous myeloid and lymphoid tumors, who had been followed up at the Outpatient Department of the Hematology Research Center, Ministry of Health of the Russian Federation. The distribution of patients by nosological entities was as follows: 17 (85%) patients with myeloproliferative diseases (MPDs) concurrent with lymphoproliferative diseases (LPDs) and 3 (15%) with two types of MPD. A special group comprised 3 patients who successively developed 3 malignant diseases: cancer/B-cell chronic lymphocytic leukemia (B-CLL)/Ph-positive chronic myeloid leukemia (Ph+CML); cancer/polycythemia vera (PCV)/B-CLL; cancer/essential thrombocythemia (ETC)/multiple myeloma (MM).

RESULTS

The Outpatient Department of the Hematology Research Center, Ministry of Health of the Russian Federation, followed up 20 patients with synchronous and metachronous tumors in 1996 to 2013. The patients' age was 42 to 82 years (64 years). The female/male ratio was 1:1.2. Metachronous tumors were 1.5-fold higher than synchronous ones. The time to detection of secondary hemoblastosis averaged 3.3 years; the longest interval was 14 years; the mean coexistence of 2 tumors was 4.8 years (1-11 years). The total length of the follow-up was 8 years (1-19 years). Among them, there were 17 (85%) patients with 2 chronic hematologic tumors with a myeloid or lymphoid phenotype; 3 (15%) of the 20 patients had 3 malignant diseases (cancer/ B-CLL)/Ph+CML, cancer/PCV/B-CLL, cancer/ETC/MM. In the group of 17 patients, 13 (76%) were diagnosed as having Ph-negative MPDs (PCV in 4 patients, primary myelofibrosis in 4, ETC in 4, undifferentiated MPD in1) and 4 (24%) patients had Ph+CML. This patient group was found to have the following LPDs: CLL in 5 (30%), hairy cell leukemia in 1 (5%), paraproteinemic hemoblastoses in 11 (65%). MPD preceded LPD in 8 (47%) patients; the development interval between two tumors averaged 6 years (1 to 14 years). LPD preceded MPD in 3 (18%) patients; the interval averaged 5 years (2 to 17 years). MPD and LPD appeared synchronously in 6 (35%) patients.

CONCLUSION

The fact that 2 malignancies or more may occur in one patient determines the need for a careful follow-up of patients with blood system diseases. The activity of one hematologic disease or another is a leading criterion for choosing a therapeutic tactic.

Impact of early molecular response to nilotinib (NIL) or imatinib (IM) on the long-term outcomes of newly diagnosed patients (pts) with chronic myeloid leukemia in chronic phase (CML-CP): Landmark analysis of 4-year (y) data from ENESTnd

7054^

Background: ENESTnd demonstrated the superiority of NIL to IM in pts with newly diagnosed CML-CP, such as higher rates of molecular response (MR) and reduced risk of progression to accelerated phase (AP)/blast crisis (BC). This landmark analysis of ENESTnd is based on BCR-ABL transcript levels at 3 mo, with 4 y of follow-up. Methods: Rates of major MR (MMR; BCR-ABLIS ≤ 0.1%), MR4.5 (BCR-ABLIS≤ 0.0032%), progression to AP/BC, overall survival (OS), and progression-free survival (PFS) in pts in the NIL 300 mg twice daily (BID; n = 282) and IM 400 mg once daily (QD; n = 283) arms of ENESTnd were evaluated based on 3-mo BCR-ABL levels (≤ 10% vs > 10%). Results: More pts treated with NIL than IM achieved BCR-ABL ≤ 10% at 3 mo (91% vs 67%; Table). Other factors associated with MR at 3 mo included Sokal risk, spleen size, chromosomal abnormalities, white blood cell count, and median dose intensity (for NIL). On both arms, pts with BCR-ABL ≤ 10% at 3 mo had significantly higher rates of MMR and MR4.5and significantly improved PFS and OS than pts with BCR-ABL > 10% at 3 mo. Of the pts with BCR-ABL > 10% at 3 mo, 2 on NIL (8%) and 14 on IM (16%) progressed to AP/BC on study. Half of these progressions occurred between 3 and 6 mo. Analyses of outcomes based on BCR-ABL levels at 6 mo were similar to findings based on 3-mo data. Conclusions: BCR-ABL levels ≤ 10% at 3 mo were associated with superior outcomes, including higher rates of MR4.5 by 4 y and lower risk of disease progression. More pts treated with NIL than IM achieved this early level of MR. Clinical trial information: NCT00471497. [Table: see text]

[Therapeutic strategy for chronic myeloid leukemia: possibilities and prospects]

Over the past decade the clinical introduction of agents that directionally blocks the activity of BCR-ABL tumor tyrosine kinase (TK) has changed the prognosis of chronic myeloid leukemia. A significant malignant Ph'-positive clone inhibition and durable remissions have made it possible to increase overall and relapse-free survival. Due to their higher life expectancy, the number of patients is on the increase and their quality of life and working capacity remain good. According to the All-Russian Register of Chronic Myeloid Leukemia, there were more than 6500 cases in the Russian Federation in 2012. Of them, 93.1% were diagnosed with the chronic phase of the disease, 6.4 and 0.4% with its accelerated phase and blast crisis, respectively. Among the BCR-ABL TK inhibitors (TKI) registered in the Russian Federation and recommended for the treatment of chronic myeloid leukemia, there are 3 medications: imatinib, nilotinib, and dasatinib. The efficiency and safety of TKI therapy have been well studied. The most important principle of treatment is to permanently affect the Ph'-positive tumor cell clone by the long-term daily use of TKls. Regular cytogenetic and molecular genetic monitoring allows adequate estimation of the leukemic clone volume and it is essential in evaluating the therapeutic effectiveness. To choose a TKI for each specific patient with regard for its best tolerability and maximum efficiency permits individualized treatment. The prospect of therapy discontinuation can be discussed only in individual patients with a durable and stable complete molecular response and only within clinical trials.

[A rare complication of imatinib mesylate therapy: drug-induced pneumonitis]

The use of imatinib mesylate (Glivec) (Novartis Pharma AG, Switzerland) that is the drug of choice in treating patients with chronic myeloid leukemia (CML) has increased 7-year survival and improved the prognosis of the disease. The drug is generally tolerated well; the proportion of patients in whom imatinib treatment results in the development of toxic complications is small. Drug-induced interstitial pneumonitis associated with imatinib therapy is a rare complication that requires timely differential diagnosis, discontinuation of an inductor (imatinib), and altered further treatment policy.

Cell Regulation of Proliferation and Differentiation ex vivo for Cells Containing Ph Chromosome in Chronic Myeloid Leukemia

Cell regulation of Ph(+)cell proliferation and differentiation has been studied ex vivo in various chronic myeloid leukemia (CML) patients. The regulation is provided by alternation of effective stages of proliferation and maturation with inhibition of Ph(+) cell proliferation by accumulating neutrophils under apoptosis blockage. The alternation of stages consists of switching stage 1 (effective proliferation) to stage 2 (effective maturation) and proceeds according to the 1/2 -1/2/1 or 2/1-2/1/2/1 schemes. The kinetic plots of alternations pass through control points of crossing plots, where the parameters of proliferation and maturation are equal. The indices of P/D efficiency (ratio of proliferation and maturation rates) are 1.06±0.23 and don't depend on time, alternation order, or sources of Ph(+) cells - CML patients. During stages alternation, conversely, the parameters of Ph+ cell proliferation and maturation vary. The proliferation stages are characterized by increased proliferating cells content, a decreased number of neutrophils, and apoptosis induction. At the maturation stages, conversely, apoptosis is inhibited, the number of mature neutrophils increases, while immature Ph(+) cells decrease. High content neutrophils inhibit the proliferation of Ph(+) cells and impair their own maturation by inversion of maturation order, probably through a feedback mechanism. The regulation differences ex vivo reveal three types of Ph(+) cells from various individual CML patients, distinguished by the number and duration of alternating stages of proliferation and maturation. Ph(+) cells types 1 and 2 have one prolonged stage of effective proliferation or effective maturation with efficiency indices P/D(1) = 1-20 or P/D(2) ⇐ 1. At the same time period, the proliferation and differentiation of the Ph(+) cells type 3 proceeds with repeated alternations of stages with P/D(1) = 1-4 or P/D(2) ⇐ 1. Type 1 Ph(+) cells (~20%) were isolated from patients in advanced stages of CML, while Ph(+) cells types 2 and 3 (30 and 50% correspondingly) were isolated from CML chronic phase patients sensitive to chemotherapy.

[Trisomy of chromosome 8 in Ph-negative cells of the bone marrow in patients with chronic myeloid leukemia treated with inhibitors of BCR-ABL tyrosine kinases]

AIM

To analyse clinical implications of chromosome 8 trisomy in Ph-negative cells of the bone marrow in patients with chronic myeloid leukemia (CML) treated with inhibitors of tyrosinkinases (ITK).

MATERIAL AND METHODS

A total of 386 patients with CML (chronic phase--288, acceleration phase--77) received imatinib (400-800 mg/day). Because of resistance and/or intolerance some patients were switched to ITK II (nilotinib, dasatinib, bozutinib). This study included 8 CML patients (7 in a chronic phase, 1 in acceleration phase) treated with BCR-ABL ITK inhibitors of the first (imatinib) and the second line (ITK-II). The standard cytogenetic examination, on demand--investigation of the interphase nuclei with FISH, in some cases morphological, cytochemical and histological examinations of the bone marrow were made.

RESULTS

The existence of a Ph-negative clone with trisomy of chromosome 8 had no negative effect on the course of the disease. The patients showed a stable hematological and cytogenetic response and no need in changing treatment policy. In long-term follow-up Ph-negative clone with trisomy of the chromosome 8 persisted without a clear trend to rise in most patients.

CONCLUSION

Detection of a Ph-negative clone with chromosome 8 trisomy at early stages suggests parallel existence of Ph-positive and Ph-negative clones. None of the patients had myelodisplasia.

[Dasatinib treatment of imatinib-resistant and imatinib-intolerant patients with chronic myeloid leukemia in a chronic phase]

AIM

To analyse resistance to imatinib therapy, efficacy and safety of dasatinib.

MATERIAL AND METHODS

A total of 18 patients with chronic myeloid leukemia (CML) in a chronic stage received dasatinib for 9-30 months (median 30 months) to September 2008.

RESULTS

Lethal outcomes during dasatinib treatment were absent. To September 2008, 16 (89%) patients were alive, 2 (11%) patients died of the disease progression after dasatinib discontinuation. A complete clinicohematological response was observed in all the patients. Major cytogenetic, complete cytogenetic, major molecular, complete molecular responses were achieved in 12 (67%), 10 (55%), 7 (39%) and 5 (28%) patients, respectively. Hematological and non-hematological toxicity occurred in 9 (50%) patients. Now 12 (67%) patients continue dasatinib treatment, in 6 (33%) patients the drug was discontinued.

CONCLUSION

The results from trials in Russian Hematological Research Center are the same as in the international study. Dasatinib is effective and well tolerated therapeutic option for imatinib-resistant patients with a chronic phase of CML.

Role of P-glycoprotein in evolution of populations of chronic myeloid leukemia cells treated with imatinib

Imatinib mesylate (imatinib) is a new generation preparation that is now successfully used for treatment of cancer, particularly for chemotherapy of chronic myeloid leukemia (CML). Imatinib inhibits the activity of chimeric kinase BCR-ABL, which is responsible for the development of CML. The goal of this study was to investigate the role of a multidrug resistance protein, P-glycoprotein (Pgp), in the evolution of CML treated with imatinib. We demonstrate here that although imatinib is a substrate for Pgp, cultured CML cells (strain K562/i-S9), overexpressing active Pgp, do not exhibit imatinib resistance. Studies of CML patients in the accelerated phase have shown variations in the number of Pgp-positive cells (Pgp+) among individual patients treated with imatinib. During treatment of patients with imatinib for 6-12 months, the number of Pgp-positive cells significantly increased in most patients. The high number of Pgp+ cells remained in patients at least for 4.5 years and correlated with active Rhodamine 123 (Rh123) efflux. Such correlation was not found in the group of imatinib-resistant patients examined 35-60 months after onset of imatinib therapy: cells from the imatinib-resistant patients exhibited efficient Rh123 efflux irrespectively of Pgp expression. We also compared the mode of Rh123 efflux by cells from CML patients who underwent imatinib treatment for 6-24 months and the responsiveness of patients to this therapy. There were significant differences in survival of patients depending on the absence or the presence of Rh123 efflux. In addition to Pgp, patients' cells expressed other transport proteins of the ABC family. Our data suggest that treatment with imatinib causes selection of leukemic stem cells characterized by expression of Pgp and other ABC transporters.

[Monitoring of minimal residual disease in patients with chronic myeloleukemia: clinical value of real-time polymerase chain reaction]

AIM

To quantitatively determine minimal residual disease (MRD) by real-time polymerase chain reaction (PCR) in patients with a chronic phase (CP) of chronic myeloid leukemia (CML).

MATERIALS AND METHODS

A molecular response was analyzed in 53 CML CP patients with incomplete and complete cptogenetic response (ICR and CCR) during imatinib therapy (median follow-up 36 months). BCR-ABL gene type p210 expression was quantitatively determined by real-time PCR under the TaqMan technology (an ICycler IQ device). The beta2 microglobulin (beta2M) gene was used as a reference gene. The results were expressed as the ratio: the number of BCR-ABL copies to that of beta2M x 10(5), as well as the difference of the common logarithm (lg) of the baseline expression level (BEL) and the result obtained: CEL lg-result lg.

RESULTS

The study revealed a correlation of the results of real-time PCR with those of cytogenetic analysis and showed it possible to study not only bone marrow, but also peripheral blood. Some negative real-time PCR results were checked using more sensitive PCR techniques. MRD was identified in most CML patients showing ICR and CCR during imatinib therapy. The reduction in BCR-ABL transcript levels by less than 2 lg (as compared to BEL) was associated with a cytogenetic recurrence and that by less than 3 lg was associated with a permanent high cytogenetic response. In patients with a cytogenetic recurrence, the median of BCR-ABL transcript levels was higher than that in patients with a permanent stable or unstable cytogenetic response. An elevation of BCR-ABL transcript levels over time antedated the development of a cytogenetic recurrence.

CONCLUSION

Quantitative monitoring by real-time PCR gives additional information on the dynamics of MRD in CML patients treated with glivec and permits improvement of study protocols for patients with CML at complete clinicohematological and cytogenetic remission.

[Recovery of polyclonial hemopoiesis in females with chronic myeloid leukemia with a complete cytogenetic response]

AIM

To study feasibility of hemopoiesis clonality determination in assessment of remission completeness in patients with chronic myeloid leukemia (CML) using polymerase chain reaction (PCR HUMARA).

MATERIAL AND METHODS

We have examined 28 patients with newly diagnosed CML, 10 CML patients with a complete cytogenetic response (CCR) to therapy with imatinib mesilate and/or alpha-interferon, 24 healthy control females. Twelve patients with untreated CML were homozygous by HUMARA gene (human androgenic receptor gene) and were withdrawn from the study. Leukocytes of peripheral blood from all the patients were investigated with PCR HUMARA for mono- or polyclonal hemopoiesis. Clonality was defined as allele proportion (a/p) of polymorphic loci of HUMARA gene. Remission completeness was confirmed cytogenetically and by molecular methods.

RESULTS

The value a/p in 10 patients with CCR varies from 0.69 to 1.33 and is similar to those in the control group.

CONCLUSION

The PCR HUMARA technique adequately assesses reduction of Ph-positive clone in CML patients with CCR and points to polyclonal hemopoiesis.

[Prognosis factors in imatinib mesilate therapy in patients with a chronic phase of Ph-positive chronic myeloid leukemia: data from a multicenter non-randomized trial in Russia]

AIM

To reveal prognostically significant factors affecting efficacy of glivek therapy in untreated (duration of the disease < or = 6 months) and pretreated (duration of the disease > 6 months) patients with chronic myeloid leukemia (CML) in a chronic phase.

MATERIAL AND METHODS

A total of 338 patients (64 untreated and 274 pretreated) with a chronic-phase CML on glivek therapy entered the trial.

RESULTS

Five-year survival on glivek was high (89, 98 and 88% in untreated and pretreated patients, respectively). Incidence of transformation in the acceleration phase and blast crisis was low both in untreated and pretreated patients (1.6 and 11%, respectively) and correlated with the rate of a complete cytogenetic response (CCR). Untreated patients had no factors affecting treatment efficacy negatively, CCR probability was 96%. Blastemia, thrombocytosis and splenomegaly reduced CCR probability significantly in pretreated patients. Slow reduction of the tumor mass, late achievement of a complete hematological response and a cytogenetic response decreased probability of CCR.

CONCLUSION

Glivek is a drug of choice for patients with chronic-phase CML. High probability of CCR both in untreated and pretreated patients lowers the risk of the disease transformation into the phase of acceleration/blast crisis and raises overall survival in both groups.

[Hyperhomocysteinemia--one of the factors underlying thrombotic complications in patients with chronic myeloproliferative diseases]

AIM

To assess incidence of hyperhomocysteinemia (HHC) in patients with chronic myeloproliferative diseases (CMPD) and to analyse possible correlation between an elevated concentration of plasma homocystein (HC) and thrombotic complications.

MATERIAL AND METHODS

The trial enrolled 61 patients: 39 CMPD patients with thrombotic complications and free of them, 22 nonhematological patients with thrombosis. The control group consisted of 40 healthy donors. The examination protocol included determination with standard methods of HC plasma concentration, platelet and plasma components of hemostasis, mutation of factor V Leiden gene, prothrombin and methylenetetrahydrofolate reductase (MTHFR).

RESULTS

Mean HC concentration in the serum in CMPD patients was 19 +/- 1.7 mcmol/l which appeared higher than in healthy donors (12 +/- 1.3 mcmol/l). The highest HC was in patients with subleukemic myelosis (SLM)--23 +/- 2.3 mcmol). No difference in HC concentration in plasma was observed in CMPD carriers of homo- or heteroxygous mutation of C667T gene or CMPD patients without the mutation. In CMPD content of factor VIII was higher in HHC than in normal HC (222 +/- 26.5 and 116 +/- 20%, respectively, p = 0.002). For von Willebrand factor 202 +/- 15.6 and 120 +/- 14.6%, respectively (p < 0.003). HC reduction in response to vitamin therapy was the greater the higher its initial level was.

CONCLUSION

There is correlation between HHC and thrombosis in CMPD patients. HC concentration may depend on the proliferative stage of CMPD. As HC is a significant independent factor of thrombotic complications risk, it is necessary to detect and treat HHC.

Phase I to II multicenter study of oblimersen sodium, a Bcl-2 antisense oligonucleotide, in patients with advanced chronic lymphocytic leukemia

PURPOSE

To determine the maximum-tolerated dose (MTD), efficacy, safety, and pharmacokinetics of oblimersen sodium in patients with advanced chronic lymphocytic leukemia (CLL).

PATIENTS AND METHODS

Eligible patients had relapsed or refractory CLL after treatment with fludarabine. Oblimersen was administered at doses ranging from 3 to 7 mg/kg/d as a 5-day continuous intravenous infusion in cycle 1 and as a 7-day continuous intravenous infusion in subsequent cycles every 3 weeks in stable or responding patients.

RESULTS

Forty patients were enrolled and treated (14 patients in phase I and 26 patients in phase II). Dose-limiting reactions in phase I included hypotension and fever, and the MTD for phase II dosing was established at 3 mg/kg/d. Two (8%) of 26 assessable patients achieved a partial response. Other evidence of antitumor activity included > or = 50% reduction in splenomegaly (seven of 17 patients; 41%), complete disappearance of hepatomegaly (two of seven patients; 29%), > or = 50% reduction of lymphadenopathy (seven of 22 patients; 32%), and > or = 50% reduction in circulating lymphocyte counts (11 of 22 patients; 50%). Adverse events included transient hypotension, fever, fatigue, night sweats, diarrhea, nausea, vomiting, hypokalemia, and cough. Plasma concentrations of oblimersen (parent drug) and its major metabolites were variable. Renal clearance represented only a small portion of total parent drug clearance.

CONCLUSION

Dosing with oblimersen sodium in patients with CLL is limited by development of a cytokine release syndrome that is characterized by fever, hypotension, and back pain. Oblimersen sodium has modest single-agent activity in heavily pretreated patients with advanced CLL, and further evaluation of its activity in combination with cytotoxic drugs is warranted.

[Cytogenetic response as a marker of efficacy of chronic myeloid leukemia therapy with a BCR-ABL thyrosine kinase inhibitor glivek]

AIM

Clinical practice with the drug glivek (imatinibe mesilate, ST1571) blocking activity of oncoprotein p210 shows that a cytogenetic response can be reached in 50-60% of patients with chronic myeloid leukemia (CML), in a late chronic phase (CP) in resistance to or intolerance of interferon alpha (IF-alpha) and in 24-43% of patients in the acceleration phase (AP). This study aimed at assessment of the rate and stability of a cytogenetic response (CR) and long-term results of survival in CML patients on glivek.

MATERIAL AND METHODS

Glivek was given to 195 CML patients (median of the treatment duration was 42 months, 1-156 months, of the patients' age--46 years). 79 patients were in CP, 116--in AP. The doses were 400 mg/day and 116 mg/day, respectively. Karyotype was studied before the treatment and later after each 6 months.

RESULTS

A considerable CR was achieved in 57% patients in CP and 44%--in AP. Of them complete CR was obtained in 48 and 35%, respectively. Marked CR is a favourable prognostic factor. Survival of patients with marked CR in CP (97% 0 and AP (89%) was significantly higher than without CR (58 and 47%, respectively, p < 0.05). Marked CR persisted in 95% cases in both phases of CML. In complete CR, a repeated study of karyotype revealed residual number of Ph+ cells both in CP and AP in 86% patients. This demonstrates necessity to take glivek continuously in achievement of a complete CR by karyotypic test. Glivek inhibits the disease progression, lowers annual lethality. 42-month (median of glivek treatment duration) overall survival reached 91 and 59% in CP and AP, respectively.

CONCLUSION

CR is an integral index prognosticating CML course. Survival rose significantly in patients with marked CR both in CP and AP of CML. Marked CR is persistent in continuous glivek therapy. The rate of a CR depends much on the disease stage.

[Acute lymphoblastic leukemias with aberrations of BCR-ABL genes]

AIM

To develop an original therapeutic strategy in Ph-positive acute lymphoblastic leukemia (ALL).

MATERIAL AND METHODS

In November 2001 Hematological Research Center (HRC) initiated the study of chimeric BCR-ABL gene. During the first stage of the study (November 2001-July 2004), 18 primary ALL patients were recruited in HRC, from July 2004 to January 2005--16 patients in HRC, N.N. Burdenko Central Military Hospital, regional Samara hospital. The diagnosis of Ph-positive ALL was established in detection of translocation t(9;22) by standard cytogenetic test or fluorescent hibridization in situ with double signal (D-FISH), or by polymerase chain reaction with reverse transcription (RT-PCR). In detection of aberration of BCR-ABL gene the patients received stem hemopoietic cells, from June 2004 imatinib was added to chemotherapy in the period of induction and consolidation.

RESULTS

Incidence rate of BCR-ABL-positive ALL by standard cytogenetic test and D-FISH makes up 20%, by RT-PCR--25%. Differences in chimeric transcripts detectability by different methods may be explained by different sensitivity of the methods. Complete hematological remissions were achieved in the majority of the patients (6 of 8) irrespective of imatinib administration. Achievement of molecular remission in BCR-ABL-positive ALL occurs also in standard chemotherapy but molecular remissions begin 2-4 months later than clinicohematological ones.

CONCLUSION

In using imatinib combination with chemotherapy, molecular remission can be achieved simultaneously with hematological one. Long-term results will be analysed later.

[Molecular-cytogenetic monitoring of different regimens of treatment in patients with chronic myeloid leukemia]

AIM

To conduct molecular-cytogenetic monitoring of bone marrow cells in different regimens of chronic myeloid leukemia (CML) treatment.

MATERIAL AND METHODS

A total of 651 samples of bone marrow from 319 CML patients were studied. 229 patients received polychemotherapy and 90 patients--interferon-alpha. Primary examination and monitoring of the treatment efficacy were performed using G-differential chromosome staining. Fluorescent in situ hybridization (FISH) was made in 75% cases.

RESULTS

Interferon therapy resulted in a significant increase in the number of complete and significant cytogenetic responses. With aggravation of the disease the above responses occurred less frequently while minor and no response are encountered more often. Treatment with interferon-alpha in combination with chemotherapy is much more effective than monotherapy with interferon.

CONCLUSION

G-differential chromosome staining karyotypes metaphases and detects clonal chromosome restructuring. Molecular-cytogenetic methods study chromosome restructuring at DNA level. FISH detects chimeric gene bcr/abl in cases when Ph-chromosome is not detectable by standard cytogenetic methods.

[Prediction of interferon therapy efficacy in chronic myeloid leukemia according to data of histomorphological study]

AIM

To investigate factors determining prognosis and efficacy of induction therapy including interferon-alpha-2b (intron-A, Schering Plough) in patients at an early chronic stage of Ph-positive chronic myeloid leukemia (CML) as shown by histomorphological examination.

MATERIAL AND METHODS

The analysis covered 52 CML patients treated at an early chronic phase with intron-A in a standard daily dose 5 IU/m2 in combination with low-dose cytosinearabinoside (10 mg/m2, s.c. , daily for 10 days of each month). The treatment efficacy was assessed by the international criteria of complete and partial hematological remission and cytogenetic response. The cytogenetic study employed the direct method, even and G-differential staining, fluorescent hybridization in situ (FISH). The sections were stained with hematoxilin-eosine by Gomori, van Gieson. Histological samples were examined with histomorphometry. Immunohistochemical examination was made on paraffin sections using a panel of monoclonal antibodies CD3, CD4, CD8, CD20, NK, PCNA, Ki-67 (Dako, Denmark).

RESULTS

Repeated assessment of histomorphological parameters such as erythroid lineage, degree of myelofibrosis and reduction of leukemic population indicate the treatment efficacy. Estimation of the level of leukemic population proliferation in trephine biopsies from CML patients with monoclonal antibodies PCNA and Ki-67 before the treatment is prognostically significant as it further correlates with the cytogenetic response (r = 0.821, p = 0.000000).

CONCLUSION

It is valid to study histomorphological picture of CML to prognosticate and assess treatment efficacy with standard doses of interferon-alpha with high probability.

[Myelofibrosis in patients with chronic myeloid leukemia treated with interferon-alpha]

Trepanobiopsies of the bone marrow were studied in 46 patients in a chronic phase of chronic myeloid leukemia in different periods after the beginning of interferon-alpha therapy. Progression of myelofibrosis was observed in 2 cases only. Regression of myelofibrosis was observed in 14 cases of 29 (34.2%). A negative correlation between reticulin myelofibrosis and response to therapy was found. Disappearance of diffuse reticulin myelofibrosis in all cases was followed by a cytogenetic response.

[Therapeutic efficacy of imatinib mesylate (glivec) in chronic phase of myeloid leukemia]

AIM

To evaluate efficacy and tolerance of glivek in chronic myeloid leukemia (CML) in patients who failed interferon-alpha (If-a) preparations.

MATERIAL AND METHODS

79 patients in a chronic phase of Ph + CML with hematological and cytogenetic resistance or intolerance of If-a. The response to glivec was assessed by achievement of a complete hematological remission and the cytogenetic effect (the degree of reduction of cell clone Ph+ in bone marrow). Tolerance and safety of the drug was studied by monthly standard clinicohematological tests.

RESULTS

Not only a hematological remission (92.4%), but also partial (46.8%) or complete (27.8%) elimination of BCR-ABL +/- cells were achieved after 12 months of the treatment. Glivec was well tolerated. Hematological toxicity primarily as neutropenia and thrombocytopenia were observed in 54.4 and 42% patients, respectively. Neutropenia of the third degree which made impossible to continue the treatment was observed in 29.1% patients; throbocytopenia of the third degree was registered in 16.5% patients. Among most frequent non-hematological side effects there were moderate edema, nausea, leg muscle convulsions, weight gain, arthralgias, skin eruption. All the complications were transient, were managed in all cases with only a short-time discontinuation of glivec therapy.

CONCLUSION

High activity of glivec at early stages of CML allows using this drug as a first-line therapy in patients with CML.

[Clinical significance of erythrocyte ferritin in refractory anemia and chronic myeloid leukemia]

AIM

To find out if the RBC ferritin elevation can serve as an additional criterion of inefficient erythropoiesis during progression of chronic myeloid leukemia (CML) and in various types of refractory anemia.

MATERIAL AND METHODS

The study group consisted of 56 MDS patients and 73 patients at various stages of CML. 20 healthy donors and 105 patients with verified inefficient erythropoiesis (20--with B12 deficiency before and after the treatment, 85--with beta-thalassemia) were the controls. A ferritin level was measured by radioimmunoassay in RBC hemolysates.

RESULTS

The RBC ferritin level in all types of refractory anemia was elevated throughout the disease course, increasing with the development of transfusion dependency. The CML progression was also accompanied by RBC ferritin level elevation associated with abnormal erythroid cell accumulation and elevation of intracellular PAS-positive substance (p < 0.05).

CONCLUSION

RBC ferritin level elevation can be considered as an additional biochemical criterion of inefficient erythropoiesis that may be useful in differentiation of anemias, adequate therapy selection and follow-up of erythropoiesis.

[Functional activity and expression of P-glycoprotein in chronic myeloid leukemia]

AIM

To evaluate the prognostic significance of P-glycoprotein (Pgp) in chronic myeloid leukemia (CML).

MATERIALS AND METHODS

Functional activity (rhodamine 123 test) and expression of Pgp (binding of UIC2 monoclonal antibodies by cells) were evaluated by flow cytofluorometry. A total of 141 samples of peripheral blood from 121 patients with various stages of CML were examined.

RESULTS

The number of patients whose cells express functionally active Pgp increases during the blast crisis (BC) in comparison with the chronic phase (CP). Repeated testing of patients with BC and CP showed that Pgp-expressing cells can disappear from the peripheral blood of patients despite the treatment by Pgp preparations and substrates. However the number of cases with expression and functional activity of Pgp increases in the course of BC. Several patients in whom functionally active Pgp was not detected during diagnosis of BC had longer BC phase than patients with the active protein.

CONCLUSION

These data suggest that active Pgp contributes to CML BC (presumably to patient's response to therapy) but this contribution is not decisive.

Studies of some mechanisms of drug resistance in chronic myeloid leukemia (CML)

CML is the myeloproliferative disorder connected with the specific chromosome translocation (9;22) and occurrence of the fusion gene/protein BCR-ABL. BCR-ABL protein is believed to inhibit apoptosis and to cause drug resistance. We investigated the correlation of two different forms of BCR-ABL mRNA in 94 pts with their overall survival. It was found that b2a2 (but not b2a3) mRNA expression correlates with longer survival of patients treated with chemotherapy. We did not find an influence of different types of BCR/ABL mRNA on the survival of pts treated with interferon-alpha. FAS/APO-1 antigen was expressed by the cells of 34% of the pts in CML blast crisis (BC) and directly correlated with the the expression of CD34, CD13 and CD14 differentiation antigens. FAS/APO-1 non-expression correlated with higher rate of remissions in BC. We investigated P-glyco-protein (Pgp) expression and functional activity in 40 BC CML pts. 2-fold shorter survival was found in the pts with Pgp expression. Pgp expression strongly correlated with CD13 antigen. Consecutive studies of pts in BC CML show that Pgp expressing cells often do not multiply in the course of BC CML. We postulate that Pgp may be regarded as differentiation marker of the cells and the unfavorable prognostic factor in BC CML.