Chronic activation of B-cell receptor (BCR) signaling via Bruton tyrosine kinase (BTK) is largely considered to be one of the primary mechanisms driving disease progression in B–Cell lymphomas. Although the BTK-targeting agent ibrutinib has shown promising clinical responses, the presence of primary or acquired resistance is common and often leads to dismal clinical outcomes. Resistance to ibrutinib therapy can be mediated through genetic mutations, up-regulation of alternative survival pathways, or other unknown factors that are not targeted by ibrutinib therapy. Understanding the key determinants, including tumor heterogeneity and rewiring of the molecular networks during disease progression and therapy, will assist exploration of alternative therapeutic strategies. Towards the goal of overcoming ibrutinib resistance, multiple alternative therapeutic agents, including second- and third-generation BTK inhibitors and immunomodulatory drugs, have been discovered and tested in both pre-clinical and clinical settings. Although these agents have shown high response rates alone or in combination with ibrutinib in ibrutinib-treated relapsed/refractory(R/R) lymphoma patients, overall clinical outcomes have not been satisfactory due to drug-associated toxicities and incomplete remission. In this review, we discuss the mechanisms of ibrutinib resistance development in B-cell lymphoma including complexities associated with genomic alterations, non-genetic acquired resistance, cancer stem cells, and the tumor microenvironment. Furthermore, we focus our discussion on more comprehensive views of recent developments in therapeutic strategies to overcome ibrutinib resistance, including novel BTK inhibitors, clinical therapeutic agents, proteolysis-targeting chimeras and immunotherapy regimens.
22 February 2024 in New England Journal of Medicine
Polycythemia vera is a chronic myeloproliferative neoplasm characterized by erythrocytosis. Rusfertide, an injectable peptide mimetic of the master iron regulatory hormone hepcidin, restricts the availability of iron for erythropoiesis. The safety and efficacy of rusfertide in patients with phlebotomy-dependent polycythemia vera are unknown. In part 1 of the international, phase 2 REVIVE trial, we enrolled patients in a 28-week dose-finding assessment of rusfertide. Part 2 was a double-blind, randomized withdrawal period in which we assigned patients, in a 1:1 ratio, to receive rusfertide or placebo for 12 weeks. The primary efficacy end point was a response, defined by hematocrit control, absence of phlebotomy, and completion of the trial regimen during part 2. Patient-reported outcomes were assessed by means of the modified Myeloproliferative Neoplasm Symptom Assessment Form (MPN-SAF) patient diary (scores range from 0 to 10, with higher scores indicating greater severity of symptoms). Seventy patients were enrolled in part 1 of the trial, and 59 were assigned to receive rusfertide (30 patients) or placebo (29 patients) in part 2. The estimated mean (±SD) number of phlebotomies per year was 8.7±2.9 during the 28 weeks before the first dose of rusfertide and 0.6±1.0 during part 1 (estimated difference, 8.1 phlebotomies per year). The mean maximum hematocrit was 44.5±2.2% during part 1 as compared with 50.0±5.8% during the 28 weeks before the first dose of rusfertide. During part 2, a response was observed in 60% of the patients who received rusfertide as compared with 17% of those who received placebo (P = 0.002). Between baseline and the end of part 1, rusfertide treatment was associated with a decrease in individual symptom scores on the MPN-SAF in patients with moderate or severe symptoms at baseline. During parts 1 and 2, grade 3 adverse events occurred in 13% of the patients, and none of the patients had a grade 4 or 5 event. Injection-site reactions of grade 1 or 2 in severity were common. In patients with polycythemia vera, rusfertide treatment was associated with a mean hematocrit of less than 45% during the 28-week dose-finding period, and the percentage of patients with a response during the 12-week randomized withdrawal period was greater with rusfertide than with placebo. (Funded by Protagonist Therapeutics; REVIVE ClinicalTrials.gov number, NCT04057040.).
19 April 2015 in Mediterranean Journal of Hematology and Infectious Diseases
Introduction:Histoplasmosis is a rare fungal disease caused by dimorphic fungi Histoplasma capsulatum. The causative fungus is present in soil, infects through inhalation and manifests in three main types-acute primary, chronic cavitary and progressive disseminated Histoplasmosis. Disseminated Histoplasmosis (DH) is defined as a clinical condition where fungus is present in more than one location. Among the forms of histoplasmosis, DH is the rarest and generally found in immune-compromised individual.Here we are presenting our experiences of the series of cases of Disseminated Histoplasmosis in immune-competent individuals who have been diagnosed in our institute in last 5 years.Materials and methods:This is a single centre retrospective observational study, from May 2009 to April 2014. Only cases with Disseminated Histoplasmosis in otherwise healthy immune-competent individuals were included in the study. The Histoplasmosis is confirmed by either presence of Histoplasma in biopsy specimen from extra-pulmonary organ or by positive growth in fungal cultureResult:Total seven patients met the inclusion criteria. Five out of 7 patients were male. The mean age was 35 years. Five of the 7 patients presented with fever for long duration. Six patients complained of significant weight loss before diagnosis. On examination, one patient had skin nodules, five patients had hepato-splenomegaly, and two patients had lymphadenopathy.The laboratory investigation revealed anaemia in six out of 7 patients, and pancytopenia in 3 patients. Two patients had features of hemophagocytic syndrome in the bone marrow.All of the patient had undergone treatment with conventional amphotericine B deoxy-cholate and azole antifungal. One patient with adrenal involvement died in hospital. The patient with skin nodule had recurrent relapses. The other patients had resolution of symptoms and clinically cured.Conclusion:Disseminated Histoplasmosis is not an uncommon etiology of fever of prolonged duration even in immuno-competent individual, and should be kept as a differential diagnosis. Targeted investigation with early bone marrow biopsy and fungal culture may help in diagnosis of DH. Imaging study to exclude adrenal involvement prevents case fatality in DH. Cytopenia may be due to secondary hemophagocytic syndrome, which improves with anti-fungal therapy. Treatment with either amphotericine B or itraconazole gives excellent outcome, though therapy may have to given for prolonged period in case of relapses.
Patients with chronic lymphocytic leukemia (CLL) have a higher risk of developing other malignancies (OMs) compared to the general population. However, the impact of CLL-related risk factors and CLL-directed treatment is still unclear and represents the focus of this work. We conducted a retrospective international multicenter study to assess the incidence of OMs and detect potential risk factors in 19,705 patients with CLL, small lymphocytic lymphoma, or high-count CLL-like monoclonal B-cell lymphocytosis, diagnosed between 2000 and 2016. Data collection took place between October 2020 and March 2022. In 129,254 years of follow-up after CLL diagnosis, 3513 OMs were diagnosed (27.2 OMs/1000 person-years). The most common hematological OMs were Richter transformation, myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML). Non-melanoma skin (NMSC) and prostate cancers were the most common solid tumors (STs).The only predictor for MDS and AML development was treatment with fludarabine and cyclophosphamide with/without rituximab (FC ± R) (OR = 3.7; 95% CI = 2.79-4.91; p < 0.001). STs were more frequent in males and patients with unmutated immunoglobulin heavy variable genes (OR = 1.77; 95% CI = 1.49-2.11; p < 0.001/OR = 1.89; 95% CI = 1.6-2.24; p < 0.001).CLL-directed treatment was associated with non-melanoma skin and prostate cancers (OR = 1.8; 95% CI = 1.36-2.41; p < 0.001/OR = 2.11; 95% CI = 1.12-3.97; p = 0.021). In contrast, breast cancers were more frequent in untreated patients (OR = 0.17; 95% CI = 0.08-0.33; p < 0.001).Patients with CLL and an OM had inferior overall survival (OS) than those without. AML and MDS conferred the worst OS (p < 0.001). OMs in CLL impact on OS. Treatment for CLL increased the risk for AML/MDS, prostate cancer, and NMSC. FCR was associated with increased risk for AML/MDS. AbbVie, and EU/EFPIAInnovative Medicines Initiative Joint Undertaking HARMONY grant n° 116026.
Over the past 20 years, hydroxyurea (HU) has emerged as an important therapeutic agent to augment Hb F and thus total hemoglobin (Hb) in Hb E [β26(B8)Glu→Lys; HBB: c.79G>A]-β-thalassemia (Hb E-β-thal), albeit used in varying doses with little consensus on its optimal dose. We report the interim analysis findings of a broader study to assess the impact of Comprehensive Thalassemia Care, of which the present report was a part. Sixty-one Hb E-β-thal patients who were transfusion independent or requiring occasional transfusions [β-thal intermedia (β-TI)] were randomized to one of two groups; A (n = 32) and B (n = 29) to receive 10 and 20 mg/kg/day HU, respectively. The primary objective of the study was to assess the differences in responses to different doses of HU. Secondary end points were to see the tolerability and safety of HU in different doses. Good response (GR) was defined as a rise of Hb by >1.0 g/dL; intermediate response (IR) as a rise in Hb by 0.6–1.0 g/dL anytime during the study period. No response (NR): rise in Hb by <0.5 g/dL in 12 weeks or drop in Hb level from the previous value. Over a follow-up period of 24 weeks, we had 18 (56.2%) GRs, nine (28.2%) IRs and five (15.6%) NRs, while the number of GRs, IRs and NRs in group B were five (17.2%) 12 (41.4%) and 12 (41.4%), respectively. Adverse effects were more common in group B, making this dose (20 mg/kg/day) of HU more myelo-suppressive than Hb F inducing.
1 January 2014 in Indian Journal of Medical and Paediatric Oncology
Context: The exact role of the different transcript variants of BCR-ABL in the pathogenesis of chronic myeloid leukemia (CML) and their impact on prognosis is yet to be definitely enumerated. Aims: In this study, we have tried to correlate the presenting features, risk scores and treatment response with the BCR-ABL variants detected in our patients. Settings and Design: A cross-sectional unicentric hospital-based study on 80 patients diagnosed to have CML by bone marrow cytogenetics and confirmed by reverse transcriptase-polymerase chain reaction (RT-PCR). Materials and Methods: RT-PCR for BCR-ABL was performed on consecutive patients with CML attending the CML clinic from January 2010 to December 2010.The medical charts of these patients were analyzed after a follow-up of 18 months in a retrospective manner. Statistical Analysis: Box plot and histogram was used to see the distribution of variables. t-test was performed to enumerate the difference between risk scores in two populations of patients carrying two different BCR-ABL transcript variants. Results: Nearly 56.25% of patients had b3a2 (e14a2) while 41.25% of patients showed b2a2 (e13a2) transcripts. The rest 2.5% (two patients) expressed the rare e19b2 variant. Patients with b2a2 presented with higher Sokal, Hasford and European Treatment and Outcomes Study score than their b3a2 counterpart. Different parameters such as the platelet count, leukocyte count, hemoglobin and splenomegaly showed a minor difference between the groups. More patients in the b2a2 group achieved complete hematologic response at 3 months, but it was not significant. Conclusions: Patients with b2a2 variant CML tend to present with higher risk score, but do not behave in a vastly different manner than their b3a2 counterparts.