Disease Burden Parameters Research Articles

Laboratory analysis of 124 chronic lymphocytic leukemia cases: Single center study

Abstract BACKGROUND: Chronic lymphocytic leukemia (CLL) is a disease characterized by an uncontrolled proliferation of malfunctioning mature B-lymphocytes. It represents a variable range of clinical presentation and prognoses. Understanding the demographic and cellular characteristics of CLL patients can aid in better disease management and treatment outcomes. OBJECTIVES: To identifying hematological parameters and patterns and potential markers that could assist in better diagnosis and of CLL in the local population. PATIENTS, MATERIALS AND METHODS: A retrospective analysis of 124 cases of newly diagnosed CLL was conducted. Data were collected from reports over 2 years (April 2022-April2024), including demographics, Hb levels, WBC counts, platelet counts and expression of CD markers (5, 19, 20, 23, 200, FMC7, LAIR1 and others) using flow cytometry on peripheral blood specimens. Based on FC findings, patients were categorized into two groups for better assessment; definite diagnosis CLL and possible diagnosis CLL; then further subdivided into poor prognosis CLL and good prognosis CLL. RESULTS: Male patients represented 59.5% of cases and females were 40.5% with a median age of 61 years at diagnosis. The mean Hb level was 109 ± 2 g/L, the mean WBC count was 58.0 ± 25.0 × 109/L, and the mean platelet count was 190 ± 40 × 109/L. CD5 was positive in 97.6% of cases, with CD23 in 96%. CONCLUSION: This study provides an overview of the demographic and cellular marker characteristics of CLL patients in FC unit. The findings underscore the heterogeneity of CLL immunophenotype and the importance of detailed characterization in improving patient management protocols; however, further research is warranted to correlate these findings with other parameters of disease burden and prognosis to optimize the therapeutic approaches for CLL patients.

OR27-03 Oral Infigratinib Treatment Is Well Tolerated And Significantly Increases Height Velocity In Children With Achondroplasia: Month 6 Results From The PROPEL 2 Dose-finding Study

Abstract Disclosure: R. Savarirayan: Advisory Board Member; Self; Ascendis Pharma, BioMarin, QED Therapeutics, Sanofi. Consulting Fee; Self; BioMarin. Grant Recipient; Self; Ascendis Pharma, BioMarin, QED Therapeutics, Theracon. Research Investigator; Self; Ascendis Pharma, BioMarin, QED Therapeutics, Theracon. J. De Bergua: None. P. Arundel: None. J. Salles: None. V. Saraff: None. B. Delgado: None. A. Leiva-Gea: None. H. McDevitt: None. M.P. Nicolino: None. M. Rossi: Advisory Board Member; Self; BioMarin. M. Salcedo: None. V. Cormier-Daire: Advisory Board Member; Self; BioMarin. M. Skae: None. P. Kannu: Advisory Board Member; Self; Novartis, Ipsen. Grant Recipient; Self; CIHR. M.B. Bober: Advisory Board Member; Self; Biomarin. Consulting Fee; Self; Ascendis Pharma, BioMarin, Pfizer, QED Therapeutics. Grant Recipient; Self; Ascendis Pharma, BioMarin, Pfizer, QED Therapeutics. Research Investigator; Self; Ascendis Pharma, BioMarin, Pfizer, QED Therapeutics. J. Phillips: None. H. Saal: Advisory Board Member; Self; Alexion. Grant Recipient; Self; Alexion, BioMarin, Pfizer, QED Therapeutics. Research Investigator; Self; Alexion, BioMarin, Pfizer, QED Therapeutics. P. Harmatz: Consulting Fee; Self; Audentes, Aeglea, Homology, JCR, Denali, Inventiva, Paradigm, Capsida, Chiesi, Avrobio. Grant Recipient; Self; BioMarin, Inventiva. Research Investigator; Self; BioMarin, Shire/Takeda, QED, RegenXbio, Denali, Ascendis, Amicus, Allievex, JCR, Orphazyme, Idorsia, Sangamo. C.P. Burren: Grant Recipient; Self; Amgen, Pfizer, QED Therapeutics. Research Investigator; Self; Amgen, Pfizer, QED Therapeutics. T. Candler: None. T. Cho: Employee; Self; QED Therapeutics. Stock Owner; Self; QED Therapeutics. E. Muslimova: Employee; Self; QED Therapeutics. Stock Owner; Self; QED Therapeutics. R. Weng: Employee; Self; QED Therapeutics. Stock Owner; Self; QED Therapeutics. S. Raj: None. J. Hoover-Fong: Consulting Fee; Self; Pfizer/Therachon, BioMarin, QED Therapeutics, Sanofi, Ascendis Pharma. Grant Recipient; Self; Pfizer/Therachon, BioMarin, Ascendis Pharma. Research Investigator; Self; Pfizer/Therachon, BioMarin, Ascendis Pharma. M. Irving: Advisory Board Member; Self; Ascendis Pharma, BioMarin, QED Therapeutics, Sanofi, Therachon/Pfizer. Speaker; Self; BioMarin, QED Therapeutics. D. Rogoff: Employee; Self; QED Therapeutics. Stock Owner; Self; QED Therapeutics. Background: Achondroplasia (ACH), the most common short-limbed skeletal dysplasia, is characterized by impaired endochondral ossification resulting from gain-of-function pathogenic variants in the fibroblast growth factor receptor 3 (FGFR3) gene, a negative regulator of endochondral bone growth. People with ACH are at risk for several significant co-morbidities, including compression of the brainstem due to foramen magnum stenosis, sleep-disordered breathing, chronic otitis media with conductive hearing loss, and symptomatic spinal stenosis. Infigratinib is an oral, selective FGFR1-3 tyrosine kinase inhibitor being investigated for the treatment of children with ACH in a phase 2 interventional study (PROPEL 2). Methods: PROPEL 2 (NCT04265651) is a phase 2 dose-finding, open-label study of infigratinib in children 3−11 years of age with ACH who participated for ≥6 months in PROPEL (NCT04035811), a non-interventional clinical assessment study. The PROPEL 2 dose-escalation (DE) phase comprises 5 ascending dose cohorts ranging from 0.016 mg/kg/day to 0.25 mg/kg/day. The primary endpoints are safety; change from baseline (BL) in annualized height velocity (AHV); and infigratinib pharmacokinetics in this population. Secondary endpoints include changes from BL in body proportions, and changes in quality of life. Other parameters of disease burden are evaluated as exploratory endpoints. Summary: Children enrolled in the PROPEL 2 DE phase completed ≥6 months of treatment at the assigned cohort dose. Cohorts 1-3 (n=37; doses 0.016, 0.032, and 0.064 mg/kg/day) did not show a significant increase in AHV and these doses were assessed as non-efficacious. Treatment at the cohort 4 dose (0.128 mg/kg/day) resulted in an increase in AHV from BL of 1.52 cm/year in children ≥5 years old (n=11; p=0.02). Infigratinib at the cohort 5 dose (n=10 with month 6 data, 0.25 mg/kg/day) resulted in a significant mean increase from BL of 3.03 cm/year (p=0.0022). In children considered responders (Δ in AHV ≥25% from BL, n=8/10), the mean change in AHV at the cohort 5 dose was +3.81±1.8 cm/year, with a median of +4.14 cm/year. Infigratinib was well tolerated with no serious AEs or AEs that led to study discontinuation, with most AEs mild or moderate in severity. At the cohort 5 dose level, no grade 3 AEs or treatment-related AEs were reported. Conclusion: Oral infigratinib in children with ACH, up to a dose of 0.25 mg/kg/day, was well tolerated and showed dose-dependent increases in AHV, with a significant mean change from BL of +3.03cm/year at the cohort 5 dose. The safety and efficacy of this oral, once-daily dose of infigratinib at 0.25 mg/kg/day will be further explored in a phase 3 randomized controlled study. If these phase 2 data are confirmed, infigratinib could potentially offer children with ACH the first safe and effective oral therapy to improve growth, enhance functionality and decrease medical complications. Presentation: Saturday, June 17, 2023

THU165 PROPEL, PROPEL 2 And PROPEL OLE Studies Of Infigratinib In Children With Achondroplasia: Design And Status Of 3 Ongoing Trials

Abstract Disclosure: R. Savarirayan: Advisory Board Member; Self; Ascendis Pharma, BioMarin, QED Therapeutics, Sanofi. Consulting Fee; Self; BioMarin. Grant Recipient; Self; Ascendis Pharma, BioMarin, QED Therapeutics, Therachon. Research Investigator; Self; Ascendis Pharma, BioMarin, QED Therapeutics, Therachon. J. De Bergua: None. P. Arundel: None. H. McDevitt: None. V. Cormier-Daire: Advisory Board Member; Self; BioMarin. V. Saraff: None. M. Skae: None. B. Delgado: None. A. Leiva-Gea: None. M. Salcedo: None. J. Salles: None. M.P. Nicolino: None. M. Rossi: Advisory Board Member; Self; BioMarin. P. Kannu: Advisory Board Member; Self; Novartis, Ipsen. Grant Recipient; Self; CIHR. M. Bober: Advisory Board Member; Self; Biomarin. Consulting Fee; Self; Ascendis Pharma, BioMarin, Pfizer, QED Therapeutics. Grant Recipient; Self; Ascendis Pharma, BioMarin, Pfizer, QED Therapeutics. Research Investigator; Self; Ascendis Pharma, BioMarin, Pfizer, QED Therapeutics. J. Phillips III: None. H. Saal: Advisory Board Member; Self; Alexion. Grant Recipient; Self; Alexion, BioMarin, Pfizer, QED Therapeutics. Research Investigator; Self; Alexion, BioMarin, Pfizer, QED Therapeutics. P. Harmatz: Consulting Fee; Self; Audentes, Aeglea, Homology, JCR, Denali, Inventiva, Paradigm, Capsida, Chiesi, Avrobio. Grant Recipient; Self; BioMarin, Inventiva. Research Investigator; Self; BioMarin, Shire/Takeda, QED Therapeutics, RegenXbio, Denali, Ascendis, Amicus, Allievex, JCR, Orphazyme, Idorsia, Sangamo. C. Burren: Grant Recipient; Self; Amgen, Pfizer, QED Therapeutics. Research Investigator; Self; Amgen, Pfizer, QED Therapeutics. T. Candler: None. T. Cho: Employee; Self; QED Therapeutics. Stock Owner; Self; QED Therapeutics. E. Muslimova: Employee; Self; QED Therapeutics. Stock Owner; Self; QED Therapeutics. R. Weng: Employee; Self; QED Therapeutics. Stock Owner; Self; QED Therapeutics. D. Rogoff: Employee; Self; QED Therapeutics. Stock Owner; Self; QED Therapeutics. J. Hoover-Fong: Consulting Fee; Self; Pfizer/Therachon, BioMarin, QED Therapeutics, Sanofi, Ascendis Pharma. Grant Recipient; Self; Pfizer/Therachon, BioMarin, Ascendis Pharma. Research Investigator; Self; Pfizer/Therachon, BioMarin, Ascendis Pharma. M. Irving: Advisory Board Member; Self; Ascendis Pharma, BioMarin, QED Therapeutics, Sanofi, Therachon/Pfizer. Speaker; Self; BioMarin, QED Therapeutics. Background: Achondroplasia (ACH), the most common short-limbed skeletal dysplasia, is characterized by defective endochondral ossification resulting from gain-of-function mutations in the fibroblast growth factor receptor 3 (FGFR3) gene, a negative regulator of endochondral bone formation. Infigratinib is a selective, orally bioavailable FGFR1-3 tyrosine kinase inhibitor being investigated for the treatment of ACH in the observational and 2 interventional studies, as detailed below. Methods: PROPEL (NCT04035811) is a non-interventional clinical assessment study designed to characterize the natural history of ∼250 children 2.5 to <17 years of age with ACH over a 6−24-month period. Primary objective: collect baseline height velocity measurements in children who may participate in an interventional study with infigratinib. Primary endpoint: annualized growth velocity (AGV). Further objectives: collect other baseline growth measurements; evaluate exploratory biomarker indicators of growth; assess ACH-related medical events reported as medical history, or non-treatment adverse events (AEs), health-related quality of life, body pain, functional abilities and cognitive functions in children with ACH. PROPEL 2 (NCT04265651) is a phase 2, open-label study of infigratinib in children 3−11 years of age with ACH who completed ≥6 months of observation in PROPEL. This study includes dose-escalation (extended dose-finding treatment phase, n≥40), a pharmacokinetics sub-study (n≥18), and a dose-expansion phase (n≈20) to confirm the selected dose and provide evidence of efficacy. Primary endpoints: AEs; change from baseline in AGV; and infigratinib pharmacokinetics. Secondary endpoints: safety/tolerability of infigratinib; changes from baseline in anthropometric parameters. Exploratory outcomes: changes in quality of life (QoL) and other parameters of disease burden. PROPEL OLE (NCT05145010) is a phase 2, open-label extension study in ∼230 children who completed an interventional study with infigratinib and, potentially, in ≤50 infigratinib-naïve children. Primary objectives: safety, tolerability; and efficacy of long-term daily doses of infigratinib. Secondary objectives: changes in other indicators of growth/development, skeletal abnormalities, QoL/disease burden, and cognitive functions. Children may receive infigratinib until they reach final height. Summary: The PROPEL, PROPEL 2, and PROPEL OLE studies are ongoing. Together, they are intended to contribute to the understanding of the natural history of ACH, provide key evidence on the safety and efficacy of oral infigratinib, including QoL and skeletal changes in children with ACH, and inform the design of future studies in this setting. Presentation: Thursday, June 15, 2023

PSAT106 Infigratinib in Children with Achondroplasia: Design of the PROPEL, PROPEL2 and PROPEL OLE Studies

Abstract Background Achondroplasia (ACH), the most common non-lethal form of skeletal dysplasia, is characterized by defective endochondral ossification resulting from gain-of-function mutations in the fibroblast growth factor receptor 3 (FGFR3) gene, a negative regulator of endochondral bone formation. Infigratinib, a selective, orally bioavailable FGFR1–3 tyrosine kinase inhibitor, has been shown to reverse established growth arrest in chondrocytes and improve foramen magnum and long bone length in Fgfr3Y367C/+ mice. Infigratinib is being investigated for the treatment of ACH in the PROPEL program of three clinical trials: 1) PROPEL, designed to collect information on the natural history of ACH; 2) PROPEL2, designed to obtain preliminary evidence of efficacy and safety and to identify the dose of infigratinib to investigate further; 3) PROPEL OLE, which is designed to evaluate the long-term efficacy and safety of infigratinib in children with ACH. Methods PROPEL (NCT04035811) is a non-interventional clinical assessment study designed to characterize the natural history of up to 200 children aged 2.5–10 years with ACH over a 6−24-month period. The primary objective is to collect baseline height velocity measurements in children who may participate in an interventional study with infigratinib. The primary endpoint is the annualized growth velocity (AGV). Further objectives are to collect other baseline growth measurements, evaluate exploratory biomarker indicators of growth, and assess ACH-related medical events reported as medical history, or non-treatment adverse events (AEs). PROPEL2 (NCT04265651) is a phase 2, open-label study of infigratinib in children aged 3−11 years with ACH who completed ≥6 months observation in PROPEL. PROPEL2 includes dose-escalation with an extended dose-finding treatment phase (n≈40), a pharmacokinetics sub-study (n≈18), followed by a dose-expansion phase (n≈20) in which children receive infigratinib for 12 months to confirm the selected dose and provide evidence of efficacy. Primary endpoints are treatment-emergent AEs, change from baseline in AGV, and infigratinib pharmacokinetics. Secondary endpoints include safety/tolerability of infigratinib and changes from baseline in anthropometric parameters, including body proportions. Exploratory outcomes include changes in QoL and other parameters of disease burden. PROPEL OLE (NCT05145010) is a phase 2, open-label extension study in up to 230 children who completed an interventional study with infigratinib and, potentially, in ≤50 who are infigratinib-naive. The primary objectives are to evaluate safety, tolerability, and efficacy of long-term daily doses of infigratinib. Secondary objectives include evaluation of changes in other indicators of growth and development, and evaluation of QoL and disease burden. Children will receive infigratinib until they reach final/near final height. Summary PROPEL, PROPEL2, and PROPEL OLE are currently ongoing. Together, these studies are intended to provide key evidence on the safety and efficacy of oral infigratinib in children with ACH and will inform the design of future studies in this setting. Presentation: Saturday, June 11, 2022 1:00 p.m. - 3:00 p.m.

Efficiency of nilotinib to target chronic phase-chronic myeloid leukaemia primary mature CD34\u2212 and immature CD34+\u2009cells

Accumulation in target cells is an essential pharmacokinetic step of targeted therapies. Tyrosine Kinase Inhibitors (TKI) against the BCR-ABL fusion protein in Chronic Phase-Chronic Myeloid Leukaemia (CP-CML) cells constitute a unique model in terms of efficacy, specificity, and in vivo demonstration of response heterogeneity by target cells. The overall therapeutic response to nilotinib is heterogeneous with no satisfactory explanation. To better understand the patients’ response heterogeneity, we quantified nilotinib uptake by primary CP-CML cells in standardized conditions using flow cytometry, which allowed also distinguishing mature (polymorphonuclear cells) from immature (CD34+) cells. Nilotinib was undetectable in 13.3% of PMN and 40% of CD34+ cells. Moreover, in CD34+ cells, intracellular nilotinib did not completely abolish BCR-ABL activity (monitored by CrkL phosphorylation inhibition), although nilotinib accumulated well in most CD34+ cell samples. Intracellular nilotinib concentration was inversely correlated with disease burden parameters, Sokal score, and early haematologic response at day 6 ± 1 only in PMN, suggesting an intrinsic ability to limit nilotinib entry in the forms with higher tumor cell burdenat diagnosis. These findings suggest that nilotinib accumulation in CP-CML cells is influenced by individual characteristics and intra-clonal heterogeneity, and might be used for pharmacokinetic studies and to assess the therapeutic response.

Quantitative Multiplex Immunohistochemistry Identifies Immunosuppression in the AML Bone Marrow and NK-Cells As Prognostic Biomarker in Intermediate-Risk Patients

BACKGROUNDA complex interaction between blasts and surrounding cells in the acute myeloid leukemia (AML) bone marrow (BM) microenvironment sustains blast proliferation and confers chemoresistance. T- and NK-cells have been shown to be dysfunctional in AML, which might be associated with immune evasion and poor prognosis. Here, we present a comprehensive analysis of the immune contexture of the AML BM at diagnosis and study its interaction with clinicopathological variables.METHODSDiagnostic BM biopsies (n=69) were collected from AML patients treated in the Helsinki University Hospital during 2005-2017 and age and gender-matched controls (n=12) to construct tissue microarrays (TMA). Using 8-plex immunohistochemistry (mIHC) and computerized image analysis, we determined cell abundance and immunophenotypic states of millions of immune cells. Immunoprofiles were integrated with a total of 120 clinicopathological variables including cytogenetics and molecular genetics, ELN (European Leukemia Net) risk classification, disease burden parameters, and patient demographics.RESULTSUnsupervised hierarchical clustering of the immunologic contexture defined by mIHC analysis grouped AML patients distinctly from control subjects (Fig 1a). By extracting significant differences (Mann-Whitney U test, q<0.05) and annotating immunologic markers as either anti-cancer or immunosuppression drivers based on literature, we observed an interesting polarization of increased immunosuppression in AML compared to control BM (Fig 1b). In AML patients, lower fraction of granzyme B expressing (GrB+) cells was noted both in CD3+CD4+ helper T-cells (10.9% vs 24.3%, q=0.002, in AML vs control BM) and CD3+CD8+ cytotoxic T-cells (23.5% vs 33.5%, q=0.02). Moreover, we observed pronounced T-cell inhibition features, such as higher proportion of regulatory T-cells (1.5% vs 0.0% FOXP3+ of helper T-cells, q<0.001), and lower expression of class I HLA in BM cells (89.1% vs 100.0%, q<0.001). Putative exhausted PD1+ T-cells were also markedly enriched in the AML BM (15.7% vs 1.7% PD1+ of helper T-cells and 13.2% vs 2.0% PD1+ of cytotoxic T-cells, q<0.001).Among the high interpatient heterogeneity, we discovered two main immune profiles. Cluster 1 was characterized with higher proportion (Log2 fold change >0.5, q<0.05) of cytotoxic T-cells and expression of CD57, CD27, and CD25 in T-cells, as well as higher expression of PD-L1 in the BM. Moreover, lower expression (Log2 fold change <0.5, q<0.05) of OX40 and CD45RO in T-cells and proportion of CD11c+BDCA1+ (type 1 myeloid dendritic cells) were observed. Patients of Cluster 1 were associated with longer event-free survival (EFS; HR 1.9, p=0.049) as well as lower age (median 53.6 vs 64.4 years, p=0.001). No connection between immunologic clusters and FLT3 or NPM1 genotype, complex karyotype, ELN risk class, blast proportion or leukocyte count was found.To support clinical decision-making in ELN 2017 intermediate-risk patients, we developed a risk stratification model focusing on this particular subgroup (n=28) using L1-penalized Cox regression. Patient age over 60 years (HR 8.1, CI95% 2.5-26.6 p<0.001) and low proportion of CD45+CD2+CD3- NK-cells (HR 0.92, CI95% 0.85-0.99 p=0.03) predicted worse EFS.In intermediate-risk patients (n=68) of a separate validation cohort (n=145) analyzed with flow cytometry, low NK cell proportion and high age predicted worse EFS (HR 2.7 CI95% 1.6-4.6 p<0.001) and OS (HR 3.9 CI95% 2.1-7.3 p<0.001) after adjusting with induction therapy protocol. Lower NK-cell proportion was associated with FLT3-ITD genotype (0.45% vs 1.1% NK-cells/all cells in FLT3-ITD+ vs FLT3-ITD- AML patients, p=0.01), and higher than median PB leukocyte (WBC) count (0.50% vs 1.9% NK-cells/all cells in patients with PB WBC ≥7.8x10E9/L vs <7.8x10E9/L, p<0.001).CONCLUSIONSUsing TMA cytometrics with mIHC and automated image analysis for detailed characterization of the immune contexture, we discovered pronounced immune exhaustion and suppression in AML BM. An aging-related immune profile was identified and was associated with poor prognosis. Furthermore, survival prediction of intermediate-risk patients might be enhanced by considering patient age and NK-cell proportion. Taken together, immunophenotyping of AML patients might improve risk stratification and identify a subgroup benefiting from immunomodulatory treatments. [Display omitted] DisclosuresPallaud:Novartis: Employment. Marques Ramos:Novartis: Employment. Porkka:Novartis: Honoraria, Research Funding; Celgene: Honoraria, Research Funding. Mustjoki:Ariad: Research Funding; Novartis: Honoraria, Research Funding; Celgene: Honoraria; Bristol-Myers Squibb: Honoraria, Research Funding; Pfizer: Honoraria, Research Funding.

Risk Factors Associated with the Development of Infusion-Related Reactions in Patients with Chronic Lymphocytic Leukaemia Treated with Anti-CD20 Monoclonal Antibodies: Analysis of the CLL11 Study Dataset

Background: The administration of anti-CD20 monoclonal antibodies (mAb) in patients with B-cell lympho-proliferative disorders is frequently accompanied by a constellation of signs and symptoms that have been labelled as infusion-related reactions (IRR). The pathophysiology of IRR remains poorly understood as do predictors of risk, which may relate to the mechanism of action of the anti-CD20, disease-related factors such as tumour burden or host factors such as polymorphisms of Fc gamma receptor 3A (FcγRIIIA).In the CLL11 trial (NCT01010061), patients with previously untreated chronic lymphocytic leukaemia and comorbidities were randomised to receive either rituximab (type I anti-CD20 mAb) or obinutuzumab (type II and glycoengineered anti-CD20 mAb) in combination with chlorambucil for six cycles. Obinutuzumab led to faster depletion of B cells and achieved an improvement in outcome parameters such as response and progression-free survival compared with the rituximab arm, but was also associated with a higher rate and increased severity of IRR. To better understand the profile of risk for IRR in patients with CLL, we performed an exploratory analysis on data obtained from patients treated with either one of the two antibodies given in combination with chlorambucil.Methods: Patients from the prospective, randomized Phase III CLL11 study who received a first infusion of obinutuzumab (N=331) or rituximab (N=326) were included. Baseline pre-treatment risk factors thought to play a possible role in the development of IRR were identified a priori and included patient demographics, concurrent conditions and premedications, parameters of disease burden, prognostic factors, laboratory variables and FcγR genotype. Baseline values for mean fluorescence intensity (MFI) of CD20, gated on the circulating CLL clone, and MFI of CD16, gated on the natural killer (NK) cell population (CD56+16+) in peripheral blood were also available for N=510 patients. The primary outcome, development of an IRR with the first infusion, was defined as the occurrence of related signs and symptoms during or within 24 hours of administration of antibody. Due to the short-term nature of the initial IRR a multivariate logistical regression analysis was performed rather than a time to event analysis. Internal validation of this model, derived from a single dataset, was conducted using the established resampling technique of bootstrapping. This assessed the proportion of times each variable retained significance at α=0.10 when the model was fitted to bootstrapped samples of the dataset.Results: Patients that appeared to be at greater risk of developing any grade of IRR with the first infusion of rituximab or obinutuzumab were those treated with obinutuzumab, those with higher surface expression CD20 on CLL cells (MFI CD20) and greater FcγRIIIA (MFI CD16) on NK cells in peripheral blood, those with higher affinity FcγRIIIA genotype (VV), more pronounced neutropenia and splenomegaly at baseline (Table 1). Higher baseline absolute lymphocyte count and the presence of respiratory comorbidity also appeared to increase risk. All variables significant for inclusion in the model are shown in Table 1. Looking at those patients treated with obinutuzumab only, the most important determinant of risk was MFI CD20 (OR 3.6 95% CI 1.6-7.9). The impact of glucocorticoid premedication in reducing risk in obinutuzumab treated patients was not sufficient to reach significance, however, patients were not randomised to this intervention.Conclusion: This work identifies novel disease- and patient-specific biological variables that appear to play a role in the development of IRR in patients with CLL treated with anti-CD20 mAb, although the treatment received (obinutuzumab >rituximab) confers greatest risk. In addition to parameters of tumour burden, target antigen expression and gene polymorphisms of FcγR also appear to contribute to the risk of developing an IRR. Our results support the hypothesis that higher rates of IRR seen with the administration of obinutuzumab may result from stronger activation upon binding to CD20 on leukemic cells and subsequent enhanced cross-linking between CD20 expressing leukemic cells and FcγRIIIA bearing effector cells. Further studies involving obinutuzumab in this patient population will be needed to externally validate the results of this exploratory analysis. [Display omitted] DisclosuresFreeman:Roche Pharmaceuticals: clinical research fellowship supported by Roche Pharmaceuticals (secondment from Bart’s) Other. Dixon:Roche Pharmaceuticals: Employment. Houghton:Roche Pharmaceuticals: Employment. Humphrey:Roche: Employment. Fingerle-Rowson:Roche Pharmaceuticals: Employment. Kreuzer:Roche Pharmaceuticals: Research Funding. Engelke:Roche: Travel grants Other. Hallek:Roche Pharmaceuticals: Consultancy, Research Funding, Speakers Bureau. Goede:Bristol Myers Squibb: Honoraria; Mundipharma: Honoraria, Membership on an entity’s Board of Directors or advisory committees, Research Funding; Roche: Honoraria, Membership on an entity’s Board of Directors or advisory committees, Research Funding, Travel grants Other.

Diagnostic Findings and Treatment in a 51-Year-Old Woman With Oncogenic Osteomalacia

A 51-year-old woman presented with recurrent insufficiency fractures of the right midfoot, the left femoral condyle, and the ribs. Furthermore, she complained of unspecific muscle and joint tenderness as well as lower back pain that had evolved over the past few years. Initial laboratory testingrevealedhypophosphatemiaand elevated alkaline phosphatase levels; vitamin D and PTH were within normal limits. Subsequent analyses showed elevated levels for fibroblast growth factor 23 (FGF-23) and urinary phosphorus loss at the upper normal limit. Differential diagnoses included congenital forms of hypophosphatemicricketsandrenalphosphatewasting,aswellas (especially in a previously asymptomatic patient) oncogenic osteomalacia due to a phosphaturic mesenchymal tumor. Although bone scintigraphy performed to localize an osseous tumor was negative, whole-body positron emission tomography (PET)/computed tomography (CT) using the radiolabeled somatostatin analog [Ga]DOTATATE revealed a suspicious lesion measuring approximately 20 mm in diameter within the right gluteal region (Figure 1, A–C). Magnetic resonance imaging (MRI) for further surgical planning confirmed the PET finding (Figure 1D) and illustrated markedly increased tumor blood supply (Figure 1E). The patient underwent surgery. Macroscopy showed a sharply demarcated gray tumor without necrosis. Upon histologicalexamination, thetumorwasofmediumcelldensitywith a rich capillary supply and a characteristic deposition of a homogenous eosinophilic substance between the evenly spaced tumor cells (Figure 1, F and G). No signs of atypia, mitosis, or necrosiscouldbeobserved, thus leadingtothefinaldiagnosisof aphosphaturicmesenchymal tumorofmixedconnective tissue type (PMTMCT) (1). Postoperatively, musculoskeletal pain and tenderness relieved and biochemical parameters of disease burden (FGF-23, serum phosphorous) recovered subsequently (Figure 2). Oncogenic osteomalacia (synonym, tumor-induced osteomalacia, or TIO) is a rare cause of hypophosphatemic rickets. Main symptoms include musculoskeletal tenderness, recurrent bone marrow edema, or insufficiency fractures associated with severe hypophosphatemia, hyperphosphaturia, elevated levels of FGF-23, and typically alkaline phosphatase (2, 3). In most cases, hyperphosphaturia is caused by a benign mesenchymal tumor with unregulated secretion of phosphaturic factors/phosphatonins such as FGF-23 and secreted frizzled-related protein 4 (1, 2, 4). However, some reports indicate that this syndrome (as a paraneoplastic condition) is underdiagnosed in malignant tumors, eg, prostate, colon, and small-cell lung cancer (3). Surgical removalof the tumor is thecausative treatment that will stop phosphaturia and normalize bone metabolism (2, 4). Because these tumors may be very small and indolent and occur at unusual anatomic sites, they are generally difficult to localize. Typical manifestations include the long bones (55% of cases) and the soft tissues (45%, including the skin)—with most lesions localized in the lower limbs (ie, femur and tibia) (5). Conventional x-ray, MRI, and CT scans are usually not sufficient for tumor identification and localization. Because these tumors typically express somatostatin receptors, functional imaging with radiolabeled somatosta-

Soluble c-Met in serum of patients with multiple myeloma: correlation with clinical parameters

The receptor tyrosine kinase c-Met and its ligand, hepatocyte growth factor (HGF), play key roles in tumour genesis and metastasis and contribute in multiple myeloma pathogenesis. Substantial data support that a soluble extracellular fragment of c-Met may function as a decoy receptor that downregulates the biological effects of HGF and c-Met. We examined serum levels of soluble c-Met in patients with myeloma and healthy individuals and investigated a possible relationship with clinical disease parameters and survival. The concentration of c-Met and HGF was measured by enzyme-linked immunosorbent assay in serum (n=49) and bone marrow plasma (n=16) from patients with multiple myeloma and in serum from healthy controls (n=26). The median serum concentration of soluble c-Met was 186 ng/mL (range 22-562) in patients with multiple myeloma and 189 ng/mL (range 124-397) in healthy individuals. There was a significant negative correlation between serum c-Met levels and disease stage, bone marrow plasma cell percentage and serum concentration of M-protein. We have for the first time examined the concentration of soluble c-Met in serum from patients with myeloma and found equal median levels in patients with myeloma as a group and healthy individuals. Still, serum levels of soluble c-Met correlated negatively with parameters of disease burden in patients with myeloma. We suggest that a possible role for the c-Met ectodomain as a negative regulator of HGF/c-Met activity should be examined in multiple myeloma.

Interference with hemozoin formation represents an important mechanism of schistosomicidal action of antimalarial quinoline methanols.

BackgroundThe parasitic trematode Schistosoma mansoni is one of the major causative agents of human schistosomiasis, which afflicts 200 million people worldwide. Praziquantel remains the main drug used for schistosomiasis treatment, and reliance on the single therapy has been prompting the search for new therapeutic compounds against this disease. Our group has demonstrated that heme crystallization into hemozoin (Hz) within the S. mansoni gut is a major heme detoxification route with lipid droplets involved in this process and acting as a potential chemotherapeutical target. In the present work, we investigated the effects of three antimalarial compounds, quinine (QN), quinidine (QND) and quinacrine (QCR) in a murine schistosomiasis model by using a combination of biochemical, cell biology and molecular biology approaches.Methodology/Principal FindingsTreatment of S. mansoni-infected female Swiss mice with daily intraperitoneal injections of QN, and QND (75 mg/kg/day) from the 11th to 17th day after infection caused significant decreases in worm burden (39%–61%) and egg production (42%–98%). Hz formation was significantly inhibited (40%–65%) in female worms recovered from QN- and QND-treated mice and correlated with reduction in the female worm burden. We also observed that QN treatment promoted remarkable ultrastructural changes in male and female worms, particularly in the gut epithelium and reduced the granulomatous reaction to parasite eggs trapped in the liver. Microarray gene expression analysis indicated that QN treatment increased the expression of transcripts related to musculature, protein synthesis and repair mechanisms.ConclusionsThe overall significant reduction in several disease burden parameters by the antimalarial quinoline methanols indicates that interference with Hz formation in S. mansoni represents an important mechanism of schistosomicidal action of these compounds and points out the heme crystallization process as a valid chemotherapeutic target to treat schistosomiasis.