Nilotinib versus imatinib for the treatment of patients with newly diagnosed chronic phase, Philadelphia chromosome-positive, chronic myeloid leukaemia: 24-month minimum follow-up of the phase 3 randomised ENESTnd trial.

BACKGROUND: Nilotinib has shown greater efficacy than imatinib in patients with newly diagnosed Philadelphia chromosome-positive chronic myeloid leukaemia (CML) in chronic phase after a minimum follow-up of 12 months. We present data from the Evaluating Nilotinib Efficacy and Safety in clinical Trials-newly diagnosed patients (ENESTnd) study after a minimum follow-up of 24 months. METHODS: ENESTnd was a phase 3, multicentre, open-label, randomised study. Adult patients were eligible if they had been diagnosed with chronic phase, Philadelphia chromosome-positive CML within the previous 6 months. Patients were randomly assigned (1:1:1) to receive nilotinib 300 mg twice a day, nilotinib 400 mg twice a day, or imatinib 400 mg once a day, all administered orally, by use of a computer-generated randomisation schedule, using permuted blocks, and stratified according to Sokal score. Efficacy results are reported for the intention-to-treat population. The primary endpoint was major molecular response at 12 months, defined as BCR-ABL transcript levels on the International Scale (BCR-ABL(IS)) of 0·1% or less by real-time quantitative PCR in peripheral blood. This study is registered with ClinicalTrials.gov, number NCT00471497. FINDINGS: 282 patients were randomly assigned to receive nilotinib 300 mg twice daily, 281 to receive nilotinib 400 mg twice daily, and 283 to receive imatinib. By 24 months, significantly more patients had a major molecular response with nilotinib than with imatinib (201 [71%] with nilotinib 300 mg twice daily, 187 [67%] with nilotinib 400 mg twice daily, and 124 [44%] with imatinib; p<0·0001 for both comparisons). Significantly more patients in the nilotinib groups achieved a complete molecular response (defined as a reduction of BCR-ABL(IS) levels to ≤0·0032%) at any time than did those in the imatinib group (74 [26%] with nilotinib 300 mg twice daily, 59 [21%] with nilotinib 400 mg twice daily, and 29 [10%] with imatinib; p<0·0001 for nilotinib 300 mg twice daily vs imatinib, p=0·0004 for nilotinib 400 mg twice daily vs imatinib). There were fewer progressions to accelerated or blast phase on treatment, including clonal evolution, in the nilotinib groups than in the imatinib group (two with nilotinib 300 mg twice daily, five with nilotinib 400 mg twice daily, and 17 with imatinib; p=0·0003 for nilotinib 300 mg twice daily vs imatinib, p=0·0089 for nilotinib 400 mg twice daily vs imatinib). At 24 months, survival was comparable in all treatment groups, but fewer CML-related deaths had occurred in both the nilotinib groups than in the imatinib group (five with nilotinib 300 mg twice daily, three with nilotinib 400 mg twice daily, and ten with imatinib). Overall, the only grade 3 or 4 non-haematological adverse events that occurred in at least 2·5% of patients were headache (eight [3%] with nilotinib 300 mg twice daily, four [1%] with nilotinib 400 mg twice daily, and two [<1%] with imatinib) and rash (two [<1%], seven [3%], and five [2%], respectively). Grade 3 or 4 neutropenia was more common with imatinib than with either dose of nilotinib (33 [12%] with nilotinib 300 mg twice daily, 30 [11%] with nilotinib 400 mg twice daily, and 59 [21%] with imatinib). Serious adverse events were reported in eight additional patients in the second year of the study (four with nilotinib 300 mg twice daily, three with nilotinib 400 mg twice daily, and one with imatinib). INTERPRETATION: Nilotinib continues to show better efficacy than imatinib for the treatment of patients with newly diagnosed CML in chronic phase. These results support nilotinib as a first-line treatment option for patients with newly diagnosed disease. FUNDING: Novartis.

Chronic myelogenous leukemia: the present and the future of the TKI therapy / Leucemia mieloide crônica: o presente e o futuro dos inibidores de tirosino quinase

Impressive response rates and the good tolerability have allowed imatinib to become the gold standard frontline therapy for all CML patients in the early chronic phase. Optimal outcomes are attained with more than two thirds of the CML cases treated with standard dose imatinib (400 mg daily). Criteria to establish failure and suboptimal responses to imatinib have been defined. Treatment guidelines have also suggested imatinib dose escalation based on clinical assessments of disease response. However, despite all the effort to optimize therapy with imatinib, cases of real resistance exist. For imatinib resistant and intolerant cases, second generation powerful tyrosine kinase inhibitors (TKIs) have been developed and registered. Sequential kinase inhibitor therapy is used to overcome resistance however, a future strategy might be a combination therapy with different ABL kinase inhibitors in the same therapeutic scheme, used sequentially or simultaneousl.

Respostas impressionantes e boa tolerância transformaram o imatinibe no "padrão ouro" de tratamento de primeira linha na LMC em fase crônica precoce. Evolução favorável em mais de 2/3 dos pacientes com LMC é obtida com dose standard de 400 mg por dia. Critérios para estabelecer falha de tratamento e resposta "sub-ótima" têm sido definidos. Guidelines têm sugerido que o escalonamento da dose do imatinibe possa melhorar a resposta em subgrupo de pacientes. Entretanto, a despeito de todos os esforços para otimizar a resposta ao imatinibe, casos de resistência realmente existem. Para os casos de intolerância ou resistência ao imatinibe, inibidores potentes de segunda geração foram desenvolvidos e registrados (nilotinibe e dasatinibe). Além disto, terapêutica sequencial de inibidores podem ultrapassar a resistência, e a terapia combinada usada sequencialmente ou simultaneamente pode ser usada como estratégia futura.

New drugs in the treatment of chronic myeloid leukaemia / Novas drogas no tratamento da leucemia mielóide crônica

The introduction of the BCR-ABL kinase inhibitor, imatinib mesylate (Gleevec®, Novartis) led to significant changes in the treatment of chronic myeloid leukaemia (CML) patients. However, despite the impressive percentage of responding patients, some CML cases, particularly those in advanced phases of the disease, show primary resistance or relapse after the initial response. The second-generation BCR-ABL inhibitors nilotinib (Tasigna®, Novartis) and dasatinib (Sprycel®, Bristol-Myers Squibb) have shown significant activity in clinical trials in patients who failed imatinib therapy, but these agents are still incapable of inhibiting the T315I mutant of Bcr-Abl and present partial activity in advanced phases of CML. The acquired biological notions of the mechanisms of tyrosine kinase inhibitor (TKI) resistance has led to the development of new compounds, some of which have shown encouraging preliminary results in clinical trials, even against T315I mutants. In this paper we discuss the new emerging therapies which may overcome TKI resistance in CML patients.

A introdução do inibidor de tirosino quinase BCR-ABL mesilato de imatinibe (Glivec®, Novartis) levou a significantes mudanças no tratamento da LMC. Entretanto, a despeito de impressionante porcentagem de pacientes que respondem, alguns casos de LMC, particularmente em fases avançadas da doença mostram resistência primaria ou recidivas após terapêutica inicial. Inibidores de tirosino quinases de segunda geração como o nilotinibe (Tasigna®, Novartis) e o dasatinibe (Sprycel®, Bristol Myers Squibb) têm mostrado significante atividade nos estudos clínicos em paciente onde o imatinibe falhou. Porém, estes agentes não são capazes de inibir a mutação T315I do Bcr-Abl e apresentam atividade parcial em fases avançadas da LMC. As noções biológicas adquiridas sobre os mecanismos de resistência aos inibidores de TK levaram ao desenvolvimento de novos compostos alguns dos quais têm resultados preliminares encorajadores incluindo a mutação T315I. Neste trabalho nós discutimos os novos agentes emergentes e qual o potencial poderão atingir para ultrapassar a resistência aos inibidores de TK em pacientes com LMC.

O tratamento de LMC com novs inibidres de tirosino-quinases / New TK-inhibitors in chronic myelogenous leukemia

O uso de inibidores do gen de fusao BCR-ABL foi introduzido na prática clínica e o mesilato de imatinibe (MI) se tornou o tratamento de primeira linha na LMC. Porém, um percentual significante de pacientes apresentará resistência primária ou adquirida. Desse modo, novas drogas têm sido desenvolvidas no sentido de superar a resistência ao MI. Dasatinibe e nilotinibe têm demonstrado importância prática. Outros inibidores de TK, principalmente para superar a mutação T3151 estão em desenvolvimento.

The use of BCR-ABL fusion gene was introduced in clinical practice and the imatinib mesylate (IM) became the front line therapy for CML. However, a significant percentage of patients will present primary or acquire resistence. News drugs have been developed in order to overcome resistant to IM. Datatinib and nilotinib demonstrated to be very active and have been introduced in clinical practice. Other TK inhibitors mainly to overcome resistance to T3151I mutation are currently in development.

Interstitial deletions at the long arm of chromosome 13 may be as common as monosomies in multiple myeloma. A genotypic study.

BACKGROUND AND OBJECTIVES: Deletions at the long arm of chromosome 13, mostly at the q14, and monosomy of chromosome 13 are described to be common in multiple myeloma (MM). 13q- has been associated with an adverse outcome and it has been proposed as one of the most important prognostic factors for MM patients. Deletions of 13q14 are rare in monoclonal gammopathy of undetermined significance (MGUS) and are thus believed to be associated with the development of the full myeloma phenotype. DESIGN AND METHODS: A genotyping analysis on purified neoplastic plasma cells was performed on 14 consecutive MM cases to determine the minimally deleted region at chromosome 13. Freshly obtained bone marrow was analyzed by flow cytometry in order to establish the percentage of plasma cell infiltration (CD38+BB4+CD56+/-CD19-). Neoplastic enrichment was carried out using BB4 coated immunomagnetic beads. This method allowed us to monitor the enrichment process. DNA obtained from the enriched neoplastic population and DNA from the clean fraction was amplified using combination sets of chromosomes 12 and 13. Amplimers were run on acrylamide gels, analyzed by automatic fluorescence quantification, and their size determined using the software programs Genescan and Genotyper. RESULTS: In 11 patients electropherograms were suggestive of loss of heterozygosity (LOH) for polymorphic markers located at the long arm of chromosome 13. Four patients showed monosomy and 7 had interstitial deletions in the telomeric region. LOH was not evidenced at chromosome 12 in any sample. The minimal region with deletion was defined by the markers D13S159 (13q32.2, centromeric) and D13S1267 (13q32.3, telomeric). A gene with a potentially pathogenic role may be located in this very small region. Three patients did not show LOH at chromosome 13 by genotypic analysis; however, in one of these, proximal deletion at the long arm of chromosome 13 (13q2.1-2.2) was demonstrated by comparative genomic hybridization (CGH). INTERPRETATION AND CONCLUSIONS: These findings suggest that interstitial deletions of the long arm of chromosome 13 may be more common than previously recognized. The methodologic approach reported in this work may simplify LOH analysis in MM patients. The potential uses of genotyping analysis in risk stratification remain to be investigated.