scholarly journals Monoacylglycerol Lipase Inhibition: A Strategy to Treat Chronic Pain in a Humanized Sickle Cell Mouse Model

Blood ◽  
2021 ◽  
Vol 138 (Supplement 1) ◽  
pp. 956-956
Author(s):  
Kennedy N Goldsborough ◽  
Karan Mucchala ◽  
Kalpna Gupta ◽  
Joyce Lloyd ◽  
Hamid Akbarali ◽  
...  

Abstract Introduction: Sickle Cell Disease (SCD) is a major cause of morbidity and mortality worldwide, and affects more than 100,000 people in the US. Acute, vaso-occlusive pain crises are the hallmark of the disease and the primary cause of hospitalization. Recurrent, acute pain episodes compound and result in chronic pain for many patients, though the mechanisms of this transition are poorly understood. Although opioids remain the standard of care to treat SCD chronic pain, their myriad adverse side effects (e.g., constipation, respiratory depression, abuse liability, dependence) as well as the fact that SCD chronic pain requires prolonged opioid treatment that results in tolerance, severely limit their therapeutic utility. Thus, a pressing need exists to identify effective non-opioid analgesic strategies to reduce SCD chronic pain. Humanized mouse models of SCD, such as the Berkeley (BERK) model, provide a useful tool to investigate disease pathophysiology and evaluate novel therapeutic strategies. Dorsal Root Ganglion neurons are peripheral sensory neurons essential for pain preclinical investigations. DRG neurons from rodents in neuropathic pain models show hyperexcitability. Inhibitors of the major degradative enzyme of 2-arachidonoylglycerol, monoacylglycerol lipase (MAGL), reduce nociceptive behavior in neuropathic and inflammatory preclinical models of pain through cannabinoid receptor-dependent and -independent mechanisms. MAGL inhibitors have yet to be tested in BERK mice and we hypothesize that they will ameliorate pain-like behavior and neuronal hyperexcitability. Here we evaluate the effects of MJN110 in a series of pain-related behaviors in BERK mice. Methods: Male and female HbSS-BERK (sickle) and HbAA-BERK (control) mice were used as subjects for these experiments. Pain-like behaviors were assessed using the Von Frey, Hot Plate, and Grip Strength tests. Neuronal hyperexcitability was assessed using whole cell patch clamp electrophysiology of L4-S1 dorsal root ganglia (DRG) neurons. For the dose-response experiments, MJN-110 (1.25, 2.5, 5, and 10 mg/kg, i.p.) was administered one hour prior to testing. Data were analyzed as Student's t-test, one- and two-way ANOVAs followed by Tukey or Sidak post-hoc analysis when appropriate (p < 0.05 considered significant). Results: HbSS-BERK mice displayed profound mechanical allodynia, as well as thermal and deep tissues/musculoskeletal hyperalgesia. HbSS-BERK mice possess extremely hyperexcitable DRG neurons. MJN-110 dose-dependently reduced mechanical allodynia and thermal hyperalgesia in HbSS-BERK mice. Importantly, BERK mice given seven days of daily injections of MJN-110 (5 mg/kg) displayed sustained antinociception that did not undergo tolerance. Ongoing studies are aimed to determine whether MJN110 ameliorates the hyperexcitability of DRG neurons. Conclusion: These initial findings, not only validate that BERK mice show hypersensitive responses to mechanical and heat stimuli, but also demonstrate that neurons innervating the distal parts of BERK mice are hyperexcitable. Additionally, MJN110 reduces these hyper-nociceptive behaviors suggesting that MAGL inhibition represents a viable strategy to reduce chronic pain behaviors in the BERK mouse model. Disclosures Gupta: Tautona Group: Consultancy, Honoraria; Novartis: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; 1910 Genetics: Other: Grantee; Grifols: Other: Grantee; SCDAA: Membership on an entity's Board of Directors or advisory committees; CSL Behring LLC: Honoraria; NIH: Other: Grantee; University of Minnestoa Foundation: Other: Philanthropic Funding; Southern California Institute for Research and Education Foundation: Other: Philanthropic Funding; Cyclerion: Research Funding; UCI Foundation: Other: Philanthropic Funding. Smith: Emmaus Pharmaceuticals: Consultancy; Global Blood Therapeutics: Consultancy, Honoraria, Research Funding, Speakers Bureau; Novartis Pharmaceuticsl: Consultancy, Honoraria; Novo-Nordisk: Other: DSMB; Pfizer: Consultancy, Research Funding; Imara: Research Funding; Forma Therapeutics: Consultancy, Research Funding; Agios: Research Funding.

Blood ◽  
2021 ◽  
Vol 138 (Supplement 1) ◽  
pp. 559-559
Author(s):  
Alyssa H. Cull ◽  
Michael Spencer Chapman ◽  
Marioara Ciuculescu ◽  
Emily Mitchell ◽  
Myriam Armant ◽  
...  

Abstract Recent advances in clonal stem cell tracking strategies have enabled interrogation of unperturbed human hematopoiesis. Whole genome sequencing (WGS) can be used to map the clonal dynamics of hematopoietic stem and progenitor cells (HSPCs) by employing spontaneous somatic mutations as unique clonal tags (Lee-Six et al., Nature, 2018). These tags allow for retrospective analysis of individual stem cell clones and the construction of phylogenetic trees mapping out stem cell relatedness, with mutations being acquired in a near-linear fashion over the course of an individual's life. The unprecedented level of information obtained in these studies is particularly well-suited to understanding genomic changes in gene therapy trials aimed at curing diseases such as sickle cell disease (SCD). In addition to mapping relatedness between stem cells, sequencing data can be used to better define mutational signatures for HSPC clones that have been successfully gene-modified as well as those that lack an integrated copy of the therapeutic vector. Given this method's ability to identify low frequency mutations in individual HSPC clones, mutations with extremely low variant allele frequencies can be detected much more readily than through traditional bulk sequencing approaches, something that is particularly relevant given recent safety concerns in some SCD gene therapy trials. In this study, we have mapped the clonal dynamics of HSPCs obtained from pre- and post-gene therapy samples from 4 SCD patients who have undergone autologous gene therapy performed using a BCL11A shmiR lentivirus vector (NCT 03282656, 12-36 months follow-up). HSPCs from mobilized peripheral blood (pre-gene therapy), bone marrow aspirates (both pre- and post-gene therapy) or unmobilized peripheral blood (post-gene therapy) were expanded as single clones and 1508 individual colonies were then sequenced using WGS to an average sequencing depth of 12.3x. Initial results indicate that the mean mutation burden per cell in a pre-gene therapy sample is elevated for some patients compared to what would be expected based on patient age in similar studies. In pre-gene therapy samples, the structure of the phylogenetic trees appeared to be highly polyclonal, indicating that there were no significant clonal expansion events prior to gene therapy. In one patient where we undertook extensive profiling, approximately 15-20 excess mutations per HSPC were observed across the entire genome 24 months after transplantation, presumably acquired as a consequence of gene therapy and/or reconstitution post-transplantation, which is equivalent to approximately one year of normal ageing without a transplantation intervention. However, no clonal expansions or driver mutations were identified at this 24 month follow-up timepoint, suggesting that no strong selective advantage or pre-leukemic events were present prior to or following the gene therapy protocol. Extending this approach to a wider range and larger number of patients will allow for comprehensive mapping of the genomic landscape and clonal evolution of stem cells in sickle cell patients and will also set the stage for improved assessment of safety and potential leukemia-initiating events in the context of gene therapy. Disclosures Esrick: bluebird bio: Consultancy. Williams: bluebird bio: Membership on an entity's Board of Directors or advisory committees, Other: Insertion Site Analysis Advisory Board, Patents & Royalties: BCH licensed certain IP relevant to hemoglobinopathies to bluebird bio. The current license includes the potential for future royalty/milestone income. Bluebird has indicated they will not pursue this as a clinical program and BCH is negotiating return of, Research Funding; BioMarin: Membership on an entity's Board of Directors or advisory committees, Other: Insertion Site Advisory Board; Beam Therapeutics: Membership on an entity's Board of Directors or advisory committees, Other: Scientific Advisory Board; Emerging Therapy Solutions: Membership on an entity's Board of Directors or advisory committees, Other: Chief Scientific Chair; Geneception: Membership on an entity's Board of Directors or advisory committees, Other: Scientific Advisory Board; Alerion Biosciences: Other: Co-founder (now licensed to Avro Bio, potential for future milestones/royalties); Novartis: Membership on an entity's Board of Directors or advisory committees, Other: Steering Committee, Novartis ETB115E2201 (eltrombopag in aplastic anemia). Advisory fees donated to NAPAAC.; Orchard Therapeutics: Membership on an entity's Board of Directors or advisory committees, Other: Membership on a safety advisory board (SAB): SAB position ended 05/20/2021. Co-founder , Patents & Royalties: Potential for future royalty/milestone income, X-SCID. Provided GMP vector for clinical trial, Research Funding. Campbell: Mu Genomics: Current holder of individual stocks in a privately-held company, Membership on an entity's Board of Directors or advisory committees. Kent: STRM.bio: Research Funding.


Blood ◽  
2021 ◽  
Vol 138 (Supplement 1) ◽  
pp. 3091-3091
Author(s):  
Michael Rabaza ◽  
Maria Armila Ruiz ◽  
Liana Posch ◽  
Faiz Ahmed Hussain ◽  
Franklin Njoku ◽  
...  

Abstract Introduction Sickle cell disease (SCD) affects 1 in 365 African Americans and approximately 25 million people world-wide. A common skeletal system complication is avascular necrosis (AVN), which can cause substantial pain and a reduced quality of life. While early management of AVN is focused on increasing range of motion with physical therapy and pain relief, there are no clear predictors for who is more likely to develop AVN and earlier institution of these preventive measure could help decrease disease progression. Vascular endothelial growth factor (VEGF) is a biomarker of endothelial injury and may indicate reduced vascular supply to the femoral or humeral head. Here we describe potential risk factors and biologic pathways for AVN in SCD, as understanding these may lead to improvements in future monitoring, early detection, and early intervention practices. Methods We investigated clinical and laboratory risk factors associated with AVN in a cohort of 435 SCD patients from our center. Blood samples, clinical, and laboratory data were collected at the time of enrollment during a clinic visit. Genotyping for alpha thalassemia was performed by PCR and the serum concentration of VEGF was measured by ELISA. AVN status was confirmed by review of the medical record and available imaging. We conducted a cross-sectional analysis comparing categorical and linear variables by AVN status using the chi-square and Kruskal-Wallis test, respectively. The independent association of the clinical and laboratory variables with AVN status was determined by logistic regression analysis. The initial model included variables with a P-value < 0.1 on univariate analysis and the final model was ascertained by stepwise forward and backward selection. Median values and interquartile range (IQR) are provided. Results The median age of the cohort was 32 (IQR, 24 - 43) years, 57% (250/435) were female, and 46% (198/435) were on hydroxyurea. AVN was observed in 34% (149/435) of SCD patients. SCD patients with AVN were older, had more frequent vaso-occlusive crises requiring medical attention, and had a higher body mass index (Table I) (P ≤ 0.002). We measured VEGF in 241 of the SCD patients with serum samples available at the time of enrolment. Serum VEGF concentrations trended higher in SCD patients with versus without AVN (420 vs. 359 pg/mL, respectively; P = 0.078). In the multivariate analysis model, AVN was independently associated with increased number of vaso-occlusive crises (OR 1.1, 95% CI: 1.0 - 1.14; P = 0.02), AST concentration (natural log OR 0.5, 95% CI: 0.2 - 0.9; P = 0.03), VEGF concentration (natural log OR 1.4, 95% CI: 1.0 - 1.9; P = 0.047), and tobacco use (OR 1.9, 95% CI: 0.9 - 3.7; P = 0.078). Discussion In conclusion, we demonstrate a high prevalence of AVN in an adult cohort of SCD patients. The presence of AVN was independently associated with a greater frequency of vaso-occlusive pain episodes, which may demonstrate a shared pathophysiology between AVN and vaso-occlusion that merits further investigation. We demonstrate that serum VEGF concentrations are higher in SCD patients with AVN and may be a clinical tool to identify those at high-risk and for earlier intervention for this complication. Figure 1 Figure 1. Disclosures Gordeuk: Modus Therapeutics: Consultancy; Novartis: Research Funding; Incyte: Research Funding; Emmaus: Consultancy, Research Funding; Global Blood Therapeutics: Consultancy, Research Funding; CSL Behring: Consultancy. Saraf: Pfizer: Research Funding; Global Blood Therapeutics: Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis: Membership on an entity's Board of Directors or advisory committees, Research Funding.


Blood ◽  
2020 ◽  
Vol 136 (Supplement 1) ◽  
pp. 3-3
Author(s):  
Rita V Masese ◽  
Dominique Bulgin ◽  
Liliana Preiss ◽  
Mitchell Knisely ◽  
Eleanor Stevenson ◽  
...  

Introduction Pregnancy in sickle cell disease (SCD) is associated with an exacerbation of SCD-related complications and an increased risk of maternal complications. The increased risk is partly due to physiologic adaptations in pregnancy, which include increased metabolic demands and a hypercoagulable state. The maternal death rate for SCD is 629 per 100,000 deliveries, compared to 12 per 100,000 deliveries in black women and 6 per 100,000 deliveries in the general population (Raider et al., 2016). Studies on maternal and perinatal outcomes of patients with SCD present inconsistent and conflicting results. Some studies have reported an increase in maternal complications such as pre-eclampsia, acute chest syndrome and thromboembolic events, while other studies have reported no significant risk in adverse maternal outcomes. The inconsistent findings reported in prior studies may be attributed to small sample sizes and single-centered sites. Our study aims to determine the prevalence and predictors of maternal morbidity among participants enrolled in the SCD Implementation Consortium (SCDIC) registry, which is the largest, most geographically diverse SCD participant sample in the United States. Methods This cross-sectional study included women enrolled in the SCDIC registry who had at least one pregnancy event. The SCDIC is composed of eight academic SCD centers across the United States and one data-coordinating center. Participants were enrolled in the SCDIC registry if they were 18 to 45 years of age and had a confirmed diagnosis of SCD. Enrolled participants completed a series of surveys that collected sociodemographic information, SCD and pregnancy history and data abstractions of participants' medical records was completed. Medical complications queried during pregnancy included: vaso-occlusive episodes, acute chest syndrome, blood transfusion requirement, preeclampsia, maternal diabetes and deep venous thrombosis. Descriptive analysis of sociodemographic, clinical and maternal characteristics was conducted. Bivariate analysis was performed using Chi-Square test, Mann-Whitney U test, t-test, and logistic regressions, as appropriate. A p-value of ≤ 0.05 was considered statistically significant for all analysis. Results The study sample included 743 women who had at least one pregnancy event, and a total of 1066 live births. Almost all women (96.3%) were African American, with a median age of 21 years (inter-quartile range of 19 to 23 years) at first birth. The majority had Hb SS SCD genotype (69.5%; 513 of the 738 with SCD genotype data). Of all reported pregnancies, participants did not use hydroxyurea during conception (78%), and pregnancy (84.5%). Only 2.7 % of the women reported using fertility drugs or assisted reproductive procedures. Seventy five percent of the pregnancies that ended in live births had maternal complications. The leading complications were vaso-occlusive episodes (61.2%), pregnancy requiring blood transfusion(s) (33.2%), preeclampsia (15.4%), deep venous thrombosis (5.6%) and acute chest syndrome (7.7%). When the pregnancies were stratified by SCD genotype, women with Hb SS had a higher occurrence of acute chest syndrome (63.4% vs. 26.7%), transfusion requirement (70.8% vs. 21%) and preeclampsia (66.7% vs 22.4%). In the univariate logistic regressions, multiparous women, with a history of adverse maternal outcomes in a previous pregnancy, had higher odds of vaso-occlusive episodes (OR: 3.42; 95% CI: 2.42-4.94) acute chest syndrome (OR:4.99; 95% CI:2.56- 9.48), transfusion requirement (OR:3.86; 95% CI:2.64- 5.69), and pre-eclampsia (OR:3.36; 95% CI:2.05-5.45). Conclusion In this large multicenter registry, we found pregnant women with SCD have significant maternal complications. Early antenatal care by healthcare providers knowledgeable about risk factors for adverse maternal outcomes in SCD is essential improve maternal and fetal outcomes and reduce the maternal death rate for SCD. Disclosures Hankins: Novartis: Research Funding; Global Blood Therapeutics: Consultancy, Research Funding; MJH Life Sciences: Consultancy, Patents & Royalties; UptoDate: Consultancy; National Heart, Lung, and Blood Institute: Honoraria, Research Funding; LINKS Incorporate Foundation: Research Funding; American Society of Pediatric Hematology/Oncology: Honoraria. Treadwell:Global Blood Therapeutics: Consultancy; UpToDate: Honoraria. King:Amphivena Therapeutics: Research Funding; Bioline: Consultancy; Celgene: Consultancy; Cell Works: Consultancy; Incyte: Consultancy; Magenta Therapeutics: Membership on an entity's Board of Directors or advisory committees; Novimmune: Research Funding; RiverVest: Consultancy; Tioma Therapuetics: Consultancy; WUGEN: Current equity holder in private company. Gordeuk:CSL Behring: Consultancy, Research Funding; Global Blood Therapeutics: Consultancy, Research Funding; Imara: Research Funding; Ironwood: Research Funding; Novartis: Consultancy. Kanter:SCDAA Medical and Research Advisory Board: Membership on an entity's Board of Directors or advisory committees; AGIOS: Membership on an entity's Board of Directors or advisory committees; BEAM: Membership on an entity's Board of Directors or advisory committees; Novartis: Consultancy; GLG: Honoraria; Jeffries: Honoraria; Cowen: Honoraria; Wells Fargo: Honoraria; NHLBI Sickle Cell Advisory Board: Membership on an entity's Board of Directors or advisory committees; Medscape: Honoraria; Guidepoint Global: Honoraria; bluebird bio, inc: Consultancy, Honoraria; Sanofi: Consultancy. Glassberg:Pfizer: Research Funding; Global Blood Therapeutics: Consultancy; Eli Lilly and Company: Research Funding. Shah:Novartis: Consultancy, Research Funding, Speakers Bureau; Alexion: Speakers Bureau; CSL Behring: Consultancy; Bluebird Bio: Consultancy; Global Blood Therapeutics: Consultancy, Research Funding, Speakers Bureau.


Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 4838-4838
Author(s):  
Sophia Delicou ◽  
Michael D. Diamantidis ◽  
Konstantinos Manganas ◽  
Eftychios Eftychiadis ◽  
Despoina Pantelidou ◽  
...  

Background: Sickle cell disease (SCD) is an autosomal recessive disorder caused by a point mutation in the β-globin chain of hemoglobin that forms hemoglobin S. It is clinically characterized by complicated episodes of veno-occlusive crises (VOC), emergency room (ER) visits and uncomplicated inpatient admissions. Aim: We investigated the clinical complications and treatment choices of a large cohort of Greek SCD patients, representative of the whole country. Most importantly, this study aimed to assess patients' attitudes and beliefs regarding their enrollment in clinical trials testing new drugs. We examined the factors influencing such a participation. Patients and Methods: A total of 254 patients from 10 Thalassemia and Sickle Cell Departments across Greece (110 men/144 women), aged 18 - over 65, 210 (82.7%) with β-thalassemia/sickle cell trait and 44 (17.3%) with homozygous SCD participated in the study. The participants had variable educational and socioeconomic background. They all answered an anonymous self-report questionnaire during their medical evaluations between November 2018 and May 2019, including their demographic and clinical characteristics, their current treatment and their opinion regarding a possible participation in a clinical trial for SCD. Descriptive statistical analysis using calculated scale variables and Chi-square test were performed. Results: All participants completed the survey. During the previous year, 64 patients (25.3%) had no admissions for VOC, 128 (50.6%) had 1-5, whereas 21 (8.3%) had 5-10 and 40 (15.8%) more than 10. Except for acute pain crises, the most frequent complications were chronic pain (59%), liver/spleen dysfunction (32.4%), infectious episodes (29.5%), iron overload (23.8%) and pulmonary hypertension (20.1%). In addition to hematological care, patients seeked medical attention from expert physicians for disease complications; 77.6% of the patients reported that they yearly visited a cardiologist, 42.4% an ophthalmologist, 31.9% an orthopedic, 28.4% a pneumonologist, 28.9% a hepatologist, 12.6% an urologist, 14% a nephrologist, 11.9% an infectious disease doctor, 10.1% a pain management specialist and 8.1% a neurologist. The therapeutic approaches included daily folic acid supplementation (86.1%), vaccines (68.3%), hydroxyurea (66.3%), antibiotics (57.1%), simple pain moderators (52.4%), opioids (48.8%) and iron chelators (30.2%). Previous experience in clinical trials was reported by only 17 patients (6.9%). Regarding the patients' attitudes towards a probable clinical trial, 41.3% were positive to try new therapies, 28.3% negative and 30.4% neutral. 67.2% were satisfied with their current treatment, without excluding a potential participation in clinical trials; such treatment satisfaction correlated significantly with older age, lower income and secondary hemochromatosis under chelation treatment (p<0.05). 40% reported that they had been waiting for years for a new treatment, but 43.2% strongly denied becoming an experimental mouse model, whereas 47.3% mentioned that they would trust their doctors' advice correlating positively with male gender and higher income (p<0.05). Lower educational status, prior intake of hydroxyurea and residence/origin in the capital in contrast to the countryside (chi-square, p<0.05) significantly correlated with a potential clinical trial participation. Internet and television information motivated patients to seek more details from their doctor. Concerning the factors rated as the most important for a potential participation in a clinical trial, 7 out of 10 patients of our cohort considered of utmost equal importance the effectiveness of a probable treatment and the relative toxicity. Conclusions: Most SCD patients have chronic complications and visit specialized physicians. Since the participation of larger number of patients in clinical trials is essential for the application of novel drugs, the most important factors of our cohort are the effectiveness of a probable treatment and the relative toxicity, along with the trust to the doctor. These factors are crucial, influencing patients' decision. Even though a proportion of our patients remain skeptical towards clinical trials, an increasing number is willing to participate, which correlates positively with residence in the capital, lower educational status and prior intake of hydroxyurea. Disclosures Kattamis: Apopharma: Honoraria; Vertex: Membership on an entity's Board of Directors or advisory committees; Celgene Corporation: Honoraria, Membership on an entity's Board of Directors or advisory committees; Ionis: Membership on an entity's Board of Directors or advisory committees; ViFOR: Membership on an entity's Board of Directors or advisory committees; Novartis Oncology: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding. Symeonidis:Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Roche: Membership on an entity's Board of Directors or advisory committees, Research Funding; Pfizer: Research Funding; Novartis: Membership on an entity's Board of Directors or advisory committees, Research Funding; MSD: Membership on an entity's Board of Directors or advisory committees, Research Funding; Janssen: Membership on an entity's Board of Directors or advisory committees, Research Funding; Tekeda: Membership on an entity's Board of Directors or advisory committees, Research Funding; Sanofi: Research Funding; Gilead: Membership on an entity's Board of Directors or advisory committees, Research Funding.


Blood ◽  
2016 ◽  
Vol 128 (22) ◽  
pp. 1018-1018 ◽  
Author(s):  
Banu Aygun ◽  
Nicole Mortier ◽  
Zora R. Rogers ◽  
William Owen ◽  
Beng Fuh ◽  
...  

Abstract Background: TCD With Transfusions Changing to Hydroxyurea (TWiTCH, ClinicalTrials.gov NCT01425307), an NHLBI-sponsored Phase III multicenter trial, compared transfusions to hydroxyurea for maintaining TCD velocities in children with sickle cell anemia who previously received transfusions for abnormal TCD velocities. Iron overload was treated with serial phlebotomy in children randomized to hydroxyurea. At the first scheduled interim analysis, non-inferiority of hydroxyurea was demonstrated and the study was terminated prematurely. Methods: Participants randomized to hydroxyurea received decreasing volumes of monthly transfusions during hydroxyurea dose escalation to maximum tolerated dose (MTD), averaging 6-7 months. During this transfusion overlap period, no chelation therapy was given. After hydroxyurea MTD was reached, transfusions were discontinued and children started monthly phlebotomy if their entry liver iron concentration (LIC) by MRI-R2 (FerriScan®) was ≥2 mg Fe/g dry weight liver (DWL). The prescribed phlebotomy volume was 10 mL/kg (maximum 500 mL) with adjustments for anemia (5 mL/kg for Hb 8.0-8.5 g/dL and held if Hb <8.0 g/dL). Phlebotomy was performed over 30 minutes with immediate equal volume normal saline replacement, typically using peripheral venous access. LIC was assessed at study entry, midpoint (12 months), and exit (24 months/early closure). Ferritin was monitored monthly using a centralized laboratory. Iron loading calculations were based on actual transfusion and phlebotomy volumes. Results: Sixty children (mean age 9.7±3.2 years; range 5.2-19.0 years; 48% male) were randomized to the Hydroxyurea Treatment Arm. The average duration of previous transfusions was 4.5±2.8 years. Almost all (51/60, 85%) had previously received chelation, primarily deferasirox, and 48 (80%) were on chelation therapy at study enrollment. Hydroxyurea MTD was achieved in 57 children (95%), and 54 commenced phlebotomy (two had low iron burden with LIC <2 and one had Hb <8.0 g/dL). A total of 914 phlebotomy procedures were scheduled per protocol for these 54 children and 756 (83%) were fully completed. There were 77 procedures cancelled due to anemia and another 81 procedures cancelled due to planned anesthesia (16), provider preference (14), hydroxyurea-related cytopenia (13), intercurrent illness (11), inadequate iv access (9), family request (5) or other (13). In 94% of phlebotomy procedures that were initiated, the full volume was removed; for the remaining 6% (47 procedures), a reduced volume was removed due to loss of venous access (37), symptoms such as headache or lightheadedness (7), or other reasons (3). A total of 18 Adverse Events (17 Grade 2 and one Grade 3) occurred in 14 participants in association with phlebotomy (2.3% prevalence). The most common complication was light headedness/near-syncope (6) followed by anemia (4), hypotension (3), headache (3), and pain at the venous access site (1). One subject had a syncopal episode followed by transient weakness, which was centrally adjudicated as TIA. An average of 53.6±21.8 mL/kg blood was administered in the hydroxyurea-treated arm, which calculates to an average iron loading of 40.1±16.3 mg Fe/kg, while an average of 112 mL/kg of venous blood was removed by phlebotomy, which calculates to an average iron unloading of 36.1±15.7 mg Fe/kg. For the 54 children who received phlebotomy, the average LIC was 12.0± 9.7 mg/g at study entry, 13.4±10.3 at midpoint reflecting overlap transfusions without chelation, and 9.7±8.9 at study exit reflecting serial phlebotomy, for an average net LIC decrease of 2.3±4.1 mg/g. Average serum ferritin at study entry was 3105±741 ng/mL and 1392±1542 ng/mL at study exit. For 39 children who completed all 24 months of treatment before study closure, the overall average LIC decrease was 3.2±3.8 mg/gram DWL and 10 had final LIC measurements <3 mg Fe/g. Calculated net iron loading was not significantly associated with measured changes in LIC or ferritin. Conclusions: In the TWiTCH trial, phlebotomy was a feasible, safe, well-tolerated, and effective treatment for transfusional iron overload in children with sickle cell anemia. Although initial overlap transfusions without chelation limited the phlebotomy effects, in children who reached hydroxyurea MTD and discontinued chronic transfusions, monthly phlebotomy led to net iron unloading and lower LIC, and significantly reduced iron burden. Disclosures Rogers: Apopharma: Consultancy. Kalfa:Baxter/Baxalta/Shire: Research Funding. Kwiatkowski:Sideris Pharmaceuticals: Consultancy; Luitpold Pharmaceuticals: Membership on an entity's Board of Directors or advisory committees; Apopharma: Research Funding; Ionis pharmaceuticals: Membership on an entity's Board of Directors or advisory committees; Shire Pharmaceuticals: Consultancy. Wood:World Care Clinical: Consultancy; Biomed Informatics: Consultancy; Biomed Informatics: Consultancy; Celgene: Consultancy; Celgene: Consultancy; AMAG: Consultancy; Apopharma: Consultancy; Apopharma: Consultancy; AMAG: Consultancy; World Care Clinical: Consultancy; Vifor: Consultancy; Vifor: Consultancy; Ionis Pharmaceuticals: Consultancy; Ionis Pharmaceuticals: Consultancy. Ware:Global Blood Therapeutics: Consultancy; Biomedomics: Research Funding; Bayer Pharmaceuticals: Consultancy; Addmedica: Research Funding; Nova Laboratories: Consultancy; Bristol Myers Squibb: Research Funding.


Blood ◽  
2020 ◽  
Vol 136 (Supplement 1) ◽  
pp. 37-37
Author(s):  
Rita V Masese ◽  
Dominique Bulgin ◽  
Mitchell Knisely ◽  
Liliana Preiss ◽  
Eleanor Stevenson ◽  
...  

Introduction Sickle cell disease (SCD) is the most common inherited blood disorders in the United States. The disease predominantly affects African Americans with 1 out of every 365 individuals born with SCD. The disease is characterized by vascular inflammation and vaso-occlusion leading to numerous complications and multi-organ dysfunction. Previous studies have shown women with SCD tend to outlive their male counterparts. Other than the increased life expectancy, sex-based clinical outcome differences in SCD remain largely unknown. To better characterize sex-based differences in SCD, we assessed sociodemographic characteristics, pain, treatment characteristics, laboratory measures and complications among males and females currently enrolled in the Sickle Cell Disease Implementation Consortium (SCDIC) registry. Methods The SCDIC consists of eight academic and comprehensive SCD centers, and one data-coordinating center that received funding from the National Heart Lung and Blood Institute to improve outcomes for individuals with SCD. Participants were eligible for the enrollment in the SCDIC registry if they were 15 to 45 years of age and had a confirmed diagnosis of SCD. Participants were excluded if they had sickle cell trait or had a successful bone marrow transplant. Enrolled participants completed surveys. Data were also abstracted from the participants' medical records. Data were entered into a REDCap database and analyzed using SAS version 9.4 (SAS Institute; Cary, NC). Categorical variables were presented as frequencies and percentages, continuous variables were presented as medians and interquartile ranges (IQR) or means and standard deviations. Categorical variables were analyzed using Chi-Square or Fisher exact tests when appropriate. Continuous variables were compared using the Mann-Whitney U test or independent sample t-tests depending on the distribution. A two-sided p-value less than 0.05 was deemed significant. Results A total of 2,124 participants were included in the study. The mean (SD) age of our participants was 27.8 (7.9) years. Almost all (95.6%) were Africa American, female (56%) and had hemoglobin SS (68.2%) SCD genotype. More males (55.4 % vs. 44.6%, p &lt;0.0001) were taking hydroxyurea. Females had significantly worse reports of pain frequency and severity (p=0.0002 and &lt;0.0001 respectively), more vaso-occlusive episodes (p=0.01) and a higher occurrence of 3 or more hospital admissions in the past year (30.9 % vs. 25.5, p= 0.03). Males had significantly more skin ulcers and respiratory, musculoskeletal, genitourinary and cardiovascular complications while females had more anxiety, depression and autoimmune conditions. Males also had significantly higher creatinine, blood urea nitrogen, albumin and liver enzymes (alkaline phosphatase, aspartate and alanine aminotransferases). Females had higher fetal hemoglobin levels with and without hydroxyurea use. There were no statistical differences in ethnicity, marital and employment status. Conclusion Key differences in SCD presentation and occurrence of complications exist among males and females. Females had higher rates of depression and anxiety while males had more chronic end-organ complications that are life threatening. Our findings emphasize the need for stratification of data analysis by sex in future SCD studies. Disclosures Hankins: Global Blood Therapeutics: Consultancy, Research Funding; National Heart, Lung, and Blood Institute: Honoraria, Research Funding; LINKS Incorporate Foundation: Research Funding; American Society of Pediatric Hematology/Oncology: Honoraria; MJH Life Sciences: Consultancy, Patents & Royalties; UptoDate: Consultancy; Novartis: Research Funding. Treadwell:UpToDate: Honoraria; Global Blood Therapeutics: Consultancy. King:Tioma Therapuetics: Consultancy; WUGEN: Current equity holder in private company; RiverVest: Consultancy; Celgene: Consultancy; Cell Works: Consultancy; Incyte: Consultancy; Magenta Therapeutics: Membership on an entity's Board of Directors or advisory committees; Bioline: Consultancy; Novimmune: Research Funding; Amphivena Therapeutics: Research Funding. Gordeuk:CSL Behring: Consultancy, Research Funding; Global Blood Therapeutics: Consultancy, Research Funding; Imara: Research Funding; Ironwood: Research Funding; Novartis: Consultancy. Kanter:bluebird bio, inc: Consultancy, Honoraria; SCDAA Medical and Research Advisory Board: Membership on an entity's Board of Directors or advisory committees; AGIOS: Membership on an entity's Board of Directors or advisory committees; Novartis: Consultancy; Sanofi: Consultancy; Medscape: Honoraria; Guidepoint Global: Honoraria; GLG: Honoraria; Jeffries: Honoraria; Cowen: Honoraria; Wells Fargo: Honoraria; NHLBI Sickle Cell Advisory Board: Membership on an entity's Board of Directors or advisory committees; BEAM: Membership on an entity's Board of Directors or advisory committees. Glassberg:Eli Lilly and Company: Research Funding; Pfizer: Research Funding; Global Blood Therapeutics: Consultancy. Shah:Bluebird Bio: Consultancy; Novartis: Consultancy, Research Funding, Speakers Bureau; Global Blood Therapeutics: Consultancy, Research Funding, Speakers Bureau; CSL Behring: Consultancy; Alexion: Speakers Bureau.


Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 1098-1098
Author(s):  
Courtney W. Johnson ◽  
Suvankar Majumdar ◽  
Andrew D. Campbell ◽  
Suresh Magge ◽  
Deepika S. Darbari ◽  
...  

Abstract Background: Cerebral vasculopathy is a frequent complication of sickle cell anemia (SCA) and is associated with a high risk for stroke. This vasculopathy seen in SCA can be progressive and severe. Sickle cell patients with severe vasculopathy, including Moyamoya syndrome are at increased risk for neurological disabilities and death. While chronic transfusions decrease the risk of stroke in SCA; unfortunately, progression of vasculopathy can occur despite treatment. Limited data exists regarding long term outcomes for this population. We evaluated effectiveness of three treatment approaches at our center, namely chronic transfusions, surgical revascularization plus chronic transfusions and allogenic hematopoietic stem cell transplant (HSCT). Methods: A retrospective chart review was preformed to identify patients with SCA (hemoglobin SS, Sβ0) and severe vasculopathy including Moyamoya syndrome between 1986 to 2017. Severe vasculopathy was defined as having at least one cerebral artery with > 70% stenosis and/or occlusion as seen on MR angiogram (MRA), CT angiogram (CTA) or conventional angiogram (DSA) as determined by a neuroradiologist at our institution. Patients were identified from an institutional stroke database. Patients were included for analysis if they received at least one of the following: chronic transfusions, surgical revascularization (i.e. encephalo-duro-arterio-synagiosis (EDAS) plus chronic transfusions or HSCT. For HSCT, all graft types (bone marrow, peripheral blood stem cells, umbilical cord blood), conditioning regimens and donor types (related, unrelated and haploidentical) were included. Time to event analyses were performed from the time of intervention (transfusion, HSCT, EDAS/chronic transfusions) using overt clinical stroke, new silent infarcts, progression of vasculopathy or new vasculopathy. Survival curves were analyzed using the log-rank (Mantel-Cox) test. Results: Of 35 patients identified, 54% (n =19) underwent chronic transfusions, 23% (n=8) of patients underwent HSCT after being on chronic transfusions, 23% (n=8) underwent EDAS with chronic transfusions and 1 patient underwent each of the above three modalities (Table 1). Median age at time of intervention was similar for all three cohorts (Table 1). Males were overrepresented in all treatment arms (62.5-79% of patients). Average hemoglobin level prior to intervention was also similar: 7.6 g/dL (IQR 7.1-8.3) for the chronic transfusion cohort, 7.3 gm/dL (IQR 6.3-8.2) for the HSCT cohort, and 7.5 gm/dL (IQR 7.2-8) for the EDAS/chronic transfusion cohort. Absolute reticulocyte count was 492.9 K/ul (IQR 358.4-550) for the chronic transfusion group, 389.4 (IQR 174.3-449) for HSCT, and 250.2 (IQR 107.3-393) for EDAS/chronic transfusions (p=0.08). One patient died of overt stroke in the chronic transfusion cohort. The median follow-up times for the transfusion, HSCT and EDAS plus transfusion groups were 4.4, 2.4 and 6 years respectively. Time from date of intervention (transfusion, HSCT, EDAS) to overt clinical or silent stroke was evaluated (Fig 1). Two of the nineteen patients in the chronic transfusion cohort suffered an overt stroke, while one of eight and two of eight had strokes in the post-HSCT and EDAS plus chronic transfusion cohorts respectively. Fourteen of nineteen (74%) in the chronic transfusion cohort had progression of severe vasculopathy after being on transfusions while two of eight (25%) in the HSCT and four of the eight (50%) patients in the EDAS plus chronic transfusion cohorts had progression. The one patient with all three different interventions did not have additional infarction (clinical or silent) or vasculopathy progression during 1.5 years of follow-up. Conclusions: The risk for cerebral infarction and/or vasculopathy progression after initiation of treatment with either chronic transfusion, HSCT or EDAS is still a major concern. Our data suggest HSCT and surgical revascularization with chronic transfusion provide the greatest benefit in reducing stroke risk and HSCT reduces risk for progression of a severe vasculopathy. Additional, large population studies are needed to clarify the risk. Disclosures Majumdar: NIMHD: Research Funding. Campbell:Functional Fluitics: Membership on an entity's Board of Directors or advisory committees; Global Blood Therapeutics: Membership on an entity's Board of Directors or advisory committees, Research Funding.


Blood ◽  
2021 ◽  
Vol 138 (Supplement 1) ◽  
pp. 962-962
Author(s):  
Minke A.E. Rab ◽  
Celeste K. Kanne ◽  
Mitchel C. Berrevoets ◽  
Jennifer Bos ◽  
Brigitte A. van Oirschot ◽  
...  

Abstract Introduction: Sickle cell disease (SCD) is an umbrella term used to describe inherited anemias that originate from a mutation in HBB, the gene coding for β-globin, that causes the formation of the abnormal hemoglobin S (HbS). The two most common genotypes are HbSS, termed sickle cell anemia (SCA) and HbSC, termed hemoglobin SC disease. Due to the higher prevalence and more severe clinical symptoms in SCA, attention is focused on this latter group of patients. Patients with HbSC disease who report significant SCD related symptoms are treated largely the same as SCA patients, despite differences in disease pathophysiology. Objective: To evaluate rheological differences in red blood cells (RBC) and whole blood from individuals with SCA and HbSC, and examine for associations with clinical complications. Methods: We analyzed an adult (n=30) and pediatric cohort (n=226) of SCA and HbSC individuals. Blood samples were evaluated for percent dense red blood cells (% DRBC), whole blood viscosity, and several ektacytometry-derived parameters, such as the cell membrane stability test, osmotic gradient ektacytometry and Point of Sickling (PoS): an oxygen gradient ektacytometry-derived biomarker that depicts the oxygen tension at which sickling is initiated. Subsequently, we assessed in the pediatric cohort (189 SCA and 37 HbSC individuals) if PoS, dense RBCs or blood viscosity are associated with clinical complications. Results: In particular (micro)dense RBCs (Figure 1A and B), blood viscosity (Figure 1C) and point of sickling (PoS, Figure 1D-F), are notably different in HbSC disease compared to SCA. In SCA, PoS was associated with occurrence of acute chest syndrome (ACS, for every 10mmHg increase OR 1.84, p&lt;0.0001, adjusted OR 1.67, p=0.002), but no such association was found in children with HbSC. In contrast, we found an association of blood viscosity and ACS (OR 9.3, p=0.012; adjusted OR 13.5, p=0.015) in HbSC children, while we found no such association in SCA. No significant association of micro dense RBCs was found in SCA or HbSC children. Conclusion: We found that associations between PoS and ACS found in SCA were not found in HbSC. Instead, in HbSC ACS was associated with higher whole blood viscosity. We therefore conclude that sickling is a key factor in the pathophysiology of SCA, whereas in HbSC disease blood viscosity might play a crucial role in development of certain complications like ACS. This study suggests that complications in SCA and HbSC disease are driven by different aspects of blood abnormalities, and may warrant a distinct treatment approach. Figure 1 Figure 1. Disclosures Rab: Axcella Health: Research Funding; Agios Pharmaceuticals: Research Funding. Schutgens: Shire/Takeda: Research Funding; Pfizer: Research Funding; OctaPharma: Research Funding; Novo Nordisk: Research Funding; CSL Behring: Research Funding; Bayer: Research Funding. Wijk: Axcella health: Research Funding; Global Blood Therapeutics: Membership on an entity's Board of Directors or advisory committees, Research Funding; Agios Pharmaceuticals: Membership on an entity's Board of Directors or advisory committees, Research Funding. Van Beers: Agios Pharmaceuticals: Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis: Research Funding; RR Mechatronics: Research Funding; Pfizer: Research Funding. Sheehan: Beam Therapeutics: Research Funding; Novartis: Research Funding; Forma Therapeutics: Research Funding.


Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 991-991 ◽  
Author(s):  
Julie Kanter ◽  
Darla K Liles ◽  
Kim Smith-Whitley ◽  
Clark Brown ◽  
Abdullah Kutlar ◽  
...  

Background: Crizanlizumab, a humanized monoclonal antibody that binds P-selectin and blocks interaction with its ligands (including leukocyte PSGL-1), is under investigation for preventing vaso-occlusive crises (VOCs) in individuals with sickle cell disease (SCD). Crizanlizumab 5.0 mg/kg was shown to significantly reduce the median annual rate of VOCs by 45.3% versus placebo (Hodges-Lehmann median absolute difference of -1.01 vs placebo, 95% CI [-2.00, 0.00]; P=0.01) (Ataga et al. N Engl J Med 2017). Aims: This pooled analysis evaluated key safety endpoints in patients treated with the recommended dose of crizanlizumab (5.0 mg/kg monthly, following 2 loading doses in the first month). Methods: Data were pooled from 2 Phase II studies of SCD patients (any genotype) with a history of VOCs leading to a healthcare visit. SUSTAIN (NCT01895361) was a randomized, placebo-controlled study in patients aged 16-65 years who had experienced 2-10 VOCs in the previous 12 months. SOLACE-adults (A2202) is an ongoing, open-label PK/PD study (NCT03264989) in patients aged 16-70 years who had experienced at least 1 VOC in the previous 12 months; data cut-off for this analysis was 1 March 2019. Adverse events (AEs) were evaluated based on MedDRA v21.1. AE severity in SOLACE was assessed based on CTCAE v5; in SUSTAIN, severity was collected as mild/moderate/severe but then recategorized for this analysis to a 5-point scale similar to CTCAE grading. AEs of special interest (ie known class effects; AEs identified preclinically or in previous studies; or potentially relevant based on the mechanism of action of crizanlizumab) were also evaluated and included infections, infusion-related reactions (IRRs) and hemostatic effects. As monoclonal antibodies can induce an immune response, anti-drug antibodies (ADAs) were also measured. Results: In total, 111 patients (SUSTAIN, n=66; SOLACE, n=45) received crizanlizumab 5.0 mg/kg: 59 females (53.2%) and 52 males (46.8%). Median age was 29 years (range 16-65). The most common SCD genotypes were HbSS (n=73; 65.8%) and HbSC (n=19; 17.1%), and 75 patients (67.6%) were receiving hydroxyurea (HU). Most patients (n=67; 60.4%) had 1-4 VOCs in the previous 12 months. Median duration of exposure to crizanlizumab was 46 weeks (range 4-58). At least 1 AE was reported in 94 patients (84.7%), the most common (≥15%) being headache (n=22; 19.8%), nausea (n=18; 16.2%) and back pain (n=17; 15.3%). AEs were mild/moderate (grade 1 or 2) and resolved spontaneously in most patients; 23 patients (20.7%) had a grade 3 AE and 1 (0.9%) had a grade 4 AE (neoplasm). At least 1 serious AE was reported in 24 patients (21.6%); serious AEs with a suspected relationship to crizanlizumab were reported in 6 patients (5.4%). Twenty-eight patients (25.2%) discontinued treatment prematurely (n=23 in SUSTAIN, n=5 to date in SOLACE): discontinuations due to AEs (bradycardia and breast cancer) occurred in 2 patients (1.8%); neither was considered related to crizanlizumab. There were 2 on-treatment deaths in SUSTAIN, but neither were considered related to crizanlizumab. Infection events were reported in 51 patients (45.9%), the most common (≥5%) being upper respiratory tract infection (n=13, 11.7%) and urinary tract infection (n=11, 9.9%). There were no grade 4 infections and none led to discontinuation. Data suggest no increased risk or severity of infection in studies with crizanlizumab. Two patients (1.8%) experienced IRRs; the events were not serious and did not lead to discontinuation. Bleeding events were rare, with most observed hemostatic AEs being abnormal laboratory parameters occurring only once. Treatment-induced ADAs were transiently detected in 1 patient (0.9%) and spontaneously resolved. There were no clinically relevant laboratory (hematology, biochemistry, liver) or ECG abnormalities, or vital sign changes, and no notable differences in the AE incidence rates by gender, ethnicity or HU use. Conclusions: This pooled analysis shows that crizanlizumab 5.0 mg/kg was well tolerated, with a favorable safety profile, in patients with SCD and a history of VOCs. Most AEs were mild/moderate, and discontinuations due to AEs were infrequent. The immunogenic potential of crizanlizumab appears low and there is currently no evidence for an increased risk of infection or bleeding. SOLACE-adults and SOLACE-kids (6 months to &lt;18 years) are ongoing, and the randomized Phase III STAND trial is recruiting. Disclosures Kanter: bluebird bio, Inc.: Consultancy; SCDAA: Membership on an entity's Board of Directors or advisory committees; NHLBI: Membership on an entity's Board of Directors or advisory committees; Rockpointe: Honoraria; Peerview: Honoraria; Jeffries: Consultancy; Medscape: Honoraria; GLG: Consultancy; Cowen: Consultancy; Guidepoint Global: Consultancy; Sangamo: Consultancy, Honoraria; Modus: Consultancy, Honoraria; Novartis: Consultancy, Honoraria; Imara: Consultancy. Liles:Novartis: Other: PI on clinical trial Sickle cell ; Shire: Other: PI on clinical trial Sickle cell ; Imara: Other: PI on Clinical trial- Sickle cell . Brown:Novartis, Inc: Research Funding. Kutlar:Bluebird Bio: Other: DSMB Member; Micelle Biopharma: Other: DSMB Chair; Novartis: Consultancy; Global Blood Therapeutics, Inc. (GBT): Research Funding; Novo Nordisk: Research Funding. Elliott:Novartis: Employment, Equity Ownership. Shah:Novartis Pharmaceuticals: Employment, Other: Shareholder. Lincy:NOVARTIS PHARMA AG: Employment. Poggio:Novartis: Employment. Ataga:Advisory Board: Global Blood Therapeutics, Novartis: Membership on an entity's Board of Directors or advisory committees, Other: VINDICO WILL FORWARD DISCLOSURES ONCE RECEIVED AND SIGNED NOT RECEIVED TO DATE; VINDICO WILL FORWARD DISCLOSURES ONCE RECEIVED AND SIGNED NOT RECEIVED TO DATE: Other: VINDICO WILL FORWARD DISCLOSURES ONCE RECEIVED AND SIGNED NOT RECEIVED TO DATE; Novartis: Honoraria, Membership on an entity's Board of Directors or advisory committees; Global Blood Therapeutics: Honoraria, Membership on an entity's Board of Directors or advisory committees; Emmaus Life Sciences: Honoraria, Membership on an entity's Board of Directors or advisory committees; Bioverativ: Honoraria, Membership on an entity's Board of Directors or advisory committees.


Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 1013-1013
Author(s):  
Frédéric Galactéros ◽  
Ersi Voskaridou ◽  
Anoosha Habibi ◽  
Giovanna Cannas ◽  
Laure Joseph ◽  
...  

Hydroxyurea (HU) is approved in the EU and USA for prevention of vaso-occlusive crises (VOC) including acute chest syndromes (ACS) in patients over 2 years with sickle-cell disease (SCD). The major benefits of HU in SCD are directly related to its abilities to increase HbF, decrease sickling of red blood cells and hemolysis, leading to reduction of vaso-occlusive episodes, need for blood transfusions and consequently reduction of morbidity and mortality. Adherence to the treatment is paramount for effectiveness, but in spite of proven benefits, barriers to adherence persist.[1] ESCORT-HU study (European Sickle Cell Disease COhoRT - HydroxyUrea), is a multicentric, prospective, non-interventional European study designed to evaluate the safety profile of HU in real life. Patients were enrolled from January 2009 to June 2017 with a follow-up of up to 10 years. All interruptions and resumptions of HU treatment exceeding 15 days were recorded in this study. We hereby present the analysis of the group of patients who self-discontinued HU at least once during the study before informing their caregiver, with a view to identify potential barriers to long-term adherence. In total, 1906 patients were enrolled in ESCORT-HU from 63 centers in France, Germany, Greece and Italy. Of these, 619 patients (32%) stopped HU for over 15 days at least once, and around a third (11% of all patients) were due to patient's will. The mean duration of HU treatment before the first discontinuation was 4.8 ± 5.1 years. Data are summarized in table 1. Compared to the rest of the cohort, the 'treatment discontinuation' group had similar distribution by gender and indication for HU prescription, but a higher proportion of adults stopped HU more than 15 days. It is notable that the proportion of patients with SC genotype was higher in the 'treatment discontinuation' group (4.5% vs 1.7%). The patients in the 'treatment discontinuation' group had more frequent SCD symptoms before enrolment in the study (table 2). Hematological and clinical improvement compared to the baseline was observed in both groups. However, average mean Corpuscular Volume (MCV) and Fetal Hemoglobin percentage (HbF%) were lower and mean percentages of patients with SCD symptoms were higher over the three years of follow-up in the 'treatment discontinuation' group, suggesting that HU daily dose was insufficient (table 2). Sixty patients have no treatment resumption date reported which suggest a permanent interruption of their treatment. Among them 32% preferred to switch to another HU medicinal product and 13% have safety issue (table 3). Understanding and managing self-discontinuation of HU before taking medical advice is challenging for the physician. It is tempting to speculate that it may be due, at least in part, to lack of effectiveness potentially due to an underdosage of the treatment. Resistance to the treatment may also be suggested based on past literature data revealing a great variability in the response (determined by HbF%) to HU therapy. There is evidence that genetic modifiers affect individual response to HU.[2],[3] Finally, weariness from long-term use may also explain the patient's wish to discontinue HU. But treatment at optimal effective should be the primary goal of caregivers. [1]Smaldone A., Manwani D., Green NS, Greater number of perceived barriers to hydroxyurea associated with poorer health-related quality of life in youth with sickle cell disease, Pediatr Blood Cancer. 2019 [2] Steinberg MH, Voskaridou E, Kutlar A, Loukopoulos D, Koshy M, et al. (2003). Concordant fetal hemoglobin response to hydroxyurea in siblings with sickle cell disease. Am J Hematol 72: 121-126 [3] Ware RE, Despotovic JM, Mortier NA, Flanagan JM, He J, et al. (2011) Pharmacokinetics, pharmacodynamics, and pharmacogenetics of hydroxyurea treatment for children with sickle cell anemia. Blood 118: 4985-4991 Disclosures Galactéros: Addmedica: Membership on an entity's Board of Directors or advisory committees. Voskaridou:Celgene Corporation: Consultancy, Research Funding; Protagonist: Research Funding; Genesis: Consultancy, Research Funding; Acceleron: Consultancy, Research Funding; Addmedica: Membership on an entity's Board of Directors or advisory committees. Cannas:Addmedica: Membership on an entity's Board of Directors or advisory committees.


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