Hb Response Research Articles

Efficacy of Epoetin Alfa in Managing Symptomatic Anaemia in Low-Risk Myelodysplastic Syndromes: A Retrospective Analysis.

Background Myelodysplastic syndromes (MDS) are clonal myeloid disorders characterised by ineffective haematopoiesis, leading to anaemia that often requires dependence on red blood cell (RBC) transfusions. Epoetin alfa (Eprex®) is now a mainstay in the management of symptomatic anaemia in low-risk MDS patients, reducing transfusion dependence and improving the quality of life in this patient group. Objective This retrospective study aimed to assess the efficacy of epoetin alfa in treating symptomatic anaemia in low-risk MDS patients, focusing on transfusion independence and its relationship with baseline erythropoietin (EPO) levels and haemoglobin (Hb) response. Methods Data from 56 patients with low-risk MDS treated with epoetin alfa at Norfolk and Norwich University Hospital,Norwich, United Kingdom, between 2018 and 2023 were retrospectively analysed. Baseline EPO levels, transfusion history, Hb response, and the duration of transfusion independence were assessed. Statistical analyses were performed to evaluate the correlation between baseline characteristics and treatment outcomes. Results Among the patients, 98.2% had baseline EPO levels below the 500 IU/L threshold, with a median EPO level of 74.3 IU/L. Following an eight-week trial of 30,000 units of epoetin-alfa, 41.1% of patients showed improved Hb levels, 41.1% maintained stable Hb levels, and 17.9% experienced a decline. A significant correlation was found between lower baseline EPO levels (<250 IU/L) and a positive treatment response (p = 0.0065). Additionally, patients who required fewer transfusions before treatment had longer durations of transfusion independence (correlation coefficient = -0.40, p = 0.015). Dose escalation to 60,000 units provided a benefit to 53.3% of patients with initially stable Hb levels. The average duration of transfusion independence was 8.1 months, and patients with improved Hb levels had the longest periods of transfusion independence (p = 0.005). Conclusion Epoetin alfa is an effective therapy for managing symptomatic anaemia in low-risk MDS patients. This study highlights its efficacy and provides valuable predictive information, particularly showing that patients with lower baseline EPO levels are more likely to respond to treatment. While prior transfusion dependence did not significantly predict response to therapy in this cohort, it was associated with the duration of transfusion independence.

The clinical efficacy of combined ESA and Roxadustat treatment for renal anemia in hemodialysis patients with secondary hyperparathyroidism: A case series.

Pharmacological mechanism of Roxadustat in the treatment of renal anemia. To investigate the efficacy and safety of combined Roxadustat and erythropoiesis stimulator (ESA) treatment of renal anemia in hemodialysis patients with secondary hyperparathyroidism. A retrospective analysis was conducted on hemodialysis patients with renal anemia and secondary hyperparathyroidism treated with ESAs alone, who were admitted to our hospital from March 2022 to December 2022. The patients were treated with Roxadustat combined with ESAs for 3 months, during which oral iron supplementation was given, and the changes in Hb levels and laboratory-related indicators before and after the combined treatment were analyzed. The results showed that a total of 13 patients received combination therapy, with a significant increase in Hb compared to ESAs alone (t = -3.955, P = .002). The Hb qualification rate was 38.46%, and the ∆Hb response rate was 76.92%. The parathyroid hormone significantly decreased with a statistically significant difference (Z = -2.062b, P = .039). Hemoglobin (RBC), total iron binding capacity, and serum ferritin (male) were significantly increased compared to ESAs alone. Total cholesterol and low-density lipoprotein were significantly lower than ESAs alone. The differences in the changes in the above indicators were statistically significant (P < .05). There was no statistically significant difference in changes in other laboratory-related indicators (P > .05). No adverse reactions were observed during the combined treatment of 13 patients. The combination of Roxadustat and ESAs can effectively improve renal anemia in hemodialysis patients with secondary hyperparathyroidism, as well as improve indicators of hyperparathyroidism and blood lipid levels with high levels of safety. This combined treatment thus provides a new and safe treatment method for these patients.

Updated safety and efficacy data from the phase 3 MANIFEST-2 study of pelabresib in combination with ruxolitinib for JAK inhibitor treatment-naïve patients with myelofibrosis.

6502 Background: Pelabresib (PELA) is an oral, small-molecule, investigational BET inhibitor that aims to decrease expression of genes involved in MF. MANIFEST-2 (NCT04603495), a global, randomized, double-blind, Phase 3 study, investigated the efficacy and safety of PELA + ruxolitinib (PELA+RUX) vs placebo + RUX (PBO+RUX) in JAKi treatment-naïve patients (pts) with MF. Methods: Eligible pts had DIPSS score ≥ INT-1, platelet count ≥100 × 109/L, spleen volume ≥450 cm3, ≥2 symptoms with an average score ≥3 or total symptom score (TSS) ≥10 (MFSAF v4.0), peripheral blast count &lt;5%, and ECOG PS ≤2. Pts were randomized 1:1. PELA or PBO was administered (QD for 14 consecutive days of 21) with RUX (BID for 21 days [1 cycle]). Primary endpoint was ≥35% spleen volume reduction from baseline (BL) (SVR35) at Week (Wk) 24. Secondary endpoints included absolute change in TSS and ≥50% reduction in TSS from BL (TSS50) at Wk 24, and safety. Other endpoints included hemoglobin (Hb) response (≥1.5 g/dL mean increase from BL without transfusions in the prior 12 wks), RBC transfusion number and bone marrow fibrosis (BMF). Results: As of Aug 31, 2023, 430 pts were randomized. At Wk 24, 65.9% (141/214) vs 35.2% (76/216) (p&lt;0.001) of pts had an SVR35 response in the PELA+RUX vs PBO+RUX arms, respectively. SVR35 responders at any time were 80.4% (172/214) vs 50.0% (108/216); 80% (137/172) vs 63% (68/108) of responders reached SVR35 at Wk 12 scan; 83.7% (144/172) vs 79.6% (86/108) maintained response at cutoff. Mean change in absolute TSS was -15.99 (SE 1.028) vs -14.05 (SE 0.986) (p=0.0545), and TSS50 was 52.3% (112/214) vs 46.3% (100/216) (p=0.216) at Wk 24. There was a 2-fold difference in pts with both SVR35 and TSS50 with PELA+RUX (40.2% [86/214]) vs PBO+RUX (18.5% [40/216]). Hb response occurred in 10.7% (23/214) vs 6.0% (13/216) of pts, with differences in mean Hb levels maintained at 48 wks. In pts with anemia (Hb BL &lt;10 g/dL), Hb response occurred in 16.4% (11/67) vs 14.1% (10/71). A total of 30.8% (66/214) vs 39.8% (86/216) of required RBC transfusion during the first 24 wks. BMF improvement ≥1 grade occurred in 38.5% (40/104) vs 24.2% (24/99) of pts (odds ratio 2.09; p=0.019). Of 426 pts evaluated for safety, the most common treatment-emergent AEs (≥20%) in the PELA+RUX vs PBO+RUX arms were anemia (43.9% vs 55.6% [Grade ≥3, 23.1% vs 36.4%]), thrombocytopenia (32.1% vs 23.4% [9% vs 5.6%]), platelet count decreased (20.8% vs 15.9% [4.2% vs 0.9%]), and diarrhea (23.1% vs 18.7% [0.5% vs 1.4%]). Updated results will be presented at the congress. Conclusions: PELA+RUX significantly and durably reduced splenomegaly, with a trend toward reduced TSS, and improved anemia and BMF at Wk 24 compared with PBO+RUX in JAKi treatment-naïve pts with MF, addressing key hallmarks of MF. Resultssupport a potential paradigm shift to combination therapy for MF. CH and JM contributed equally. Clinical trial information: NCT04603495 .

#2898 Exposure response model describing hematologic changes with chronic treatment of CKD anemia with vadadustat

Abstract Background and Aims Vadadustat (VADA) is an oral hypoxia-inducible factor (HIF) prolyl hydroxylase inhibitor, a class of drugs that stabilize HIF and stimulate endogenous erythropoietin production, increasing iron mobilization and red blood cell production. VADA is approved in 36 countries globally and is indicated in the European Union for the treatment of symptomatic anaemia associated with chronic kidney disease (CKD) in adults on chronic maintenance dialysis and is an alternative to treatment with erythropoiesis-stimulating agents (ESAs). The aim of this work was to develop a predictive, semi-mechanistic model to understand the effects of VADA and erythropoiesis-stimulating agents (ESAs) on hemoglobin response and to evaluate the impact of intrinsic and extrinsic patient characteristics on that response for non-dialysis dependent (NDD) and dialysis-dependent (DD) patient populations. Method A predictive semi-mechanistic pharmacokinetic/pharmacodynamic (PK/PD) model for VADA and ESA treatment was developed using nonlinear mixed effects methods. The model describes changes in reticulocyte count (RETICs), mature erythrocytes (RBCs) and hemoglobin (Hb) as a function of drug exposure and subject-specific characteristics. The dataset was based on data from 7 Phase 1 to Phase 3 studies (Table 1; N = 894 for VADA; N = 560 for ESA modeling) in healthy volunteers and subjects with NDD- or DD-CKD who were either ESA-naïve or ESA experienced but not receiving treatment at screening. Prior population PK modeling of VADA provided estimated drug exposures for VADA-treated subjects, while dose normalized to standard units (IU/kg/wk) was used as the exposure metric for subjects on ESA. Each of these exposure metrics could vary with time, as the dose was adjusted according to observed Hb response. This work evaluated alternative model structures, as well as covariate effects affecting Hb individual response. Results A predictive semi-mechanistic pharmacokinetic/pharmacodynamic (PK/PD) model for VADA and ESA treatment was developed using nonlinear mixed effects methods. The model describes changes in reticulocyte count (RETICs), mature erythrocytes (RBCs) and hemoglobin (Hb) as a function of drug exposure and subject-specific characteristics. The dataset was based on data from 7 Phase 1 to Phase 3 studies (Table 1; N = 894 for VADA; N = 560 for ESA modeling) in healthy volunteers and subjects with NDD- or DD-CKD who were either ESA-naïve or ESA experienced but not receiving treatment at screening. Prior population PK modeling of VADA provided estimated drug exposures for VADA-treated subjects, while dose normalized to standard units (IU/kg/wk) was used as the exposure metric for subjects on ESA. Each of these exposure metrics could vary with time, as the dose was adjusted according to observed Hb response. This work evaluated alternative model structures, as well as covariate effects affecting Hb individual response. A similar model structure was found to describe early changes in RETICs and longer-term changes in Hb for both VADA and ESAs. In each case, the magnitude of response increases with increased drug exposure up to a maximum value (Emax), and the Emax values were similar between VADA and ESAs. Subject intrinsic predictors of response included eGFR, subject age, BMI, and serum albumin, while extrinsic factors affecting response included geographic region, limits on acceptable Hb values (which also differ by geographic region) and the presence of previous ESA treatment. Interestingly, Hb responses were also correlated with changes in serum hepcidin, a key regulator of iron homeostasis, following both VADA and ESA treatment. Differences between the response to VADA and ESA were also described, including differences in temporal changes in RETICs and Hb. Conclusion This model showed an exposure-response relationship between VADA or ESA treatment and changes in RETICs and Hb for ESA naïve or ESA-experienced CKD subjects. The model will be used to inform dosage recommendations for VADA based on patient characteristics.

#1194 Roxadustat in ESA converted patients with anemia of chronic kidney disease on dialysis: a secondary analysis of ROXSTAR Registry

Abstract Background and Aims Anemia is associated with increased morbidity &amp; mortality in chronic kidney disease (CKD) patients. Around 20% of patients experience erythropoiesis-stimulating agent (ESA) hypo-responsiveness and can't achieve hemoglobin (Hb) treatment target even with a high dose. Higher ESA dose is associated with undesirable outcomes. Roxadustat has demonstrated efficacy and safety in ESA converted CKD anemia patients. We conduct this secondary analysis of ROXSTAR registry (ChiCTR2100046322) to evaluate the Hb response to roxadustat in ESAs converted dialysis-dependent (DD) patients with prior weekly ESA dose ≥10000 U and &amp;lt;10000 U respectively. Method This study used existing data collected in the ROXSTAR Registry. DD patients converted from ESA treatment who received at least one dose of roxadustat, and had at least one post baseline Hb were included. We described the Hb response to roxadustat treatment in patients converted from higher ESA dose (≥10,000 U per week) and from lower ESA dose (&amp;lt;10,000 U per week) at enrollment. The changes from baseline to week 12 &amp; week 24 in Quality of Life (QoL) assessed by SF-36 Vitality &amp; Physical Function subscales, and Rapid Assessment of Physical Activity (RAPA) Strength &amp; Flexibility scores were also analyzed respectively. Results Total 666 ESA converted DD patients were included. For the higher ESA dose group, there were 426 patients (257 male [60.3%]) with a mean (standard deviation [SD]) age of 49.5 [13.1] years, the median (mix, max) dialysis duration was 31.7 (0.2, 307.8) months. For the lower ESA dose group, 240 patients (141 male [58.8%]) with a mean age of 49.7 [13.0] years were enrolled, and median dialysis duration was 36.4 (0.4, 266.1) months. The mean baseline Hb was 98.0 (14.5) g/L in the higher ESA dose group and 102.2 (12.6) g/L in the lower ESA dose group. The median prior weekly ESA dose was 10000 (10000, 50000) U and 6000.0 (300, 9000) U in higher &amp; lower ESA dose groups (Table 1). Mean weekly roxadustat dose during the first 12 weeks (correction phase) was maintained around 300 mg and then decreased to around 260 mg during 12-52 weeks (maintenance phase) for the higher ESA dose group; the dose started from around 300 mg and decreased to 270 mg during the correction phase and then gradually decreased to around 230 mg during the maintenance phase in the lower ESA dose group. The mean Hb change from baseline averaged over weeks 24-36 &amp; 36-52 was 12.1 [95% CI: 10.5, 13.7] g/L &amp; 12.3 [95% CI: 10.7, 13.9] g/L for the higher ESA dose group and 9.9 [95% CI: 8.0, 11.8] g/L &amp; 10.2 [95% CI: 8.3, 12.1] g/L for the lower ESA dose group, respectively. The proportion (%) of patients with mean Hb ≥100 g/L at the same period were 82.3% [95% CI: 78.1%, 86.6%] &amp; 83.6% [95% CI: 79.3%, 87.9%] in the higher ESA dose group and 88.4% [95% CI: 83.6%, 93.1%] &amp; 89.0% [95% CI: 84.3%, 93.7%] in the lower ESA dose group. There was no clinical meaningful change of QoL observed in either group. Conclusion ESA-converted DD patients responded well to roxadustat in terms of anemia correction and Hb maintenance to treatment target, regardless of prior ESA dose. Similar starting doses of roxadustat were used for both groups and then gradually decreased during the maintenance phase (week 12-52) compared to the correction phase (week 1-12) while the magnitude of dose decrease was greater in the lower ESA dose group.

#1168 Responsiveness to roxadustat in chronic kidney disease associated anemia patients by baseline hemoglobin: a secondary analysis of ROXSTAR Registry

Abstract Background and Aims Anemia is a common complication of chronic kidney disease (CKD), and associated with increased morbidity and mortality, as well as a reduced quality of life (QoL). Various studies have shown anemia treatment in CKD patients improved the QoL. However, in ROXSTAR Registry (ChiCTR2100046322), although roxadustat corrected anemia and maintained hemoglobin (Hb) effectively, no improvement in QoL was observed. Hence, we conduct this secondary analysis of ROXSTAR to evaluate the Hb response to roxadustat treatment and the change of QoL in dialysis-dependent (DD) and non-dialysis-dependent (NDD) patients stratified by baseline Hb. Method This was a secondary analysis using existing data collected in the ROXSTAR Registry. DD &amp; NDD Patients who received at least one dose of roxadustat and had at least one post baseline Hb were included. We described the Hb response to roxadustat in patients with lower baseline (Hb &amp;lt;80) g/L &amp; higher baseline Hb (≥80 g/L). The changes from baseline to week 12 &amp; week 24 in Quality of Life (QoL) assessed by SF-36 Vitality (V) &amp; Physical Function (PF) subscales, and Rapid Assessment of Physical Activity (RAPA) Strength &amp; Flexibility scores were also analyzed respectively. Results Overall, 1998 patients (1508 DD patients and 490 NDD patients) were included, there were 238 patients (131 male [55.0%]) with a mean (standard deviation [SD]) age of 49.1 (13.6) years in the lower baseline Hb group, and 1760 patients (947 male [53.8%]) with a mean age of 50.3 (13.5) in the higher baseline Hb group. The overall mean baseline Hb was 97.3 (13.9) g/L, with 71.4 (7.2) g/L and 100.8 (10.5) g/L in the two groups respectively. The median (min, max) ferritin and mean transferrin saturation were 149.6 (3.3, 2304.0) ng/mL &amp; 22.8% (15.5) % in the lower baseline Hb group and 169.8 (3.8, 3966.0) ng/mL &amp; 30.6% (15.7%) in the higher baseline Hb group. More patients with CRP above normal limit were in the lower baseline Hb group (30.7%) compared to patients in the other group (19.7%) (Table 1). Mean weekly roxadustat dose started at 320 mg and was maintained during the first 12 weeks (correction phase) then slightly decreased to 300 mg from week 12 until week 52 (maintenance phase) in patients with baseline Hb &amp;lt;80 g/L, while it was from 286 mg to 260 mg during the correction phase then decreased and maintained at around 230 mg from week 12 to week 52 in patients with baseline Hb ≥80 g/L. The mean Hb change from baseline averaged over weeks 24-36 and 36-52 was 31.9 [95% CI: 29.9, 33.9] g/L &amp; 33.7 [95% CI: 31.8, 35.6] g/L in the lower baseline Hb group, and 11.3 [95% CI: 10.6, 12.0] g/L &amp; 11.1 [95% CI: 10.5, 11.8] g/L in the higher baseline Hb group. The proportion (%) of patients with mean Hb ≥100 g/L averaged over the same period were 58.8% [95% CI: 51.8%, 65.7%] &amp; 68.6% [95% CI: 61.8%, 75.3%] in the lower baseline Hb group, and 86.5% [95% CI: 84.7%, 88.3%] &amp; 88.2% [95% CI: 86.5%, 90.0%] in the higher baseline Hb group. Patients with baseline Hb &amp;lt;80 g/L had numerically higher mean increases from baseline to week 12 and 24 in SF-36 V and PF sub-scores (Table 2), though no clinical meaningful change was observed in either group. Conclusion Roxadustat effectively corrected anemia in DD and NDD patients regardless of baseline Hb level. There was no clinical meaningful improvement in QoL for either group. The weekly dose of roxadustat to correct and maintain Hb was higher in patient with baseline Hb &amp;lt;80 g/L than in patients with baseline Hb ≥80 g/L.

#2352 Short-term effect of roxadustat combined with ESA treatment for anemia in patients undergoing hemodialysis with ESA hyporesponsiveness

Abstract Background and Aims The efficacy of roxadustat combined with erythropoiesis-stimulating agent (ESA) on renal anemia in maintenance hemodialysis (MHD) patients is rarely reported, especially for those with ESA hyporesponsiveness. Our study aimed to observe the short-term efficacy of roxadustat combined with ESA for those patients when they were first treated with roxadustat converted from ESA. Method Retrospective data pertaining to MHD patients with ESA hyporesponsiveness from September 2019 to June 2022 were collected. All patients had been on ESA for more than 6 months and were first treated with roxadustat. 19 patients treated with roxadustat combined with ESA and 19 patients treated with roxadustat alone were paired for analysis from 108 patients by propensity score matching. Parameters related to anemia, iron metabolism and adverse events were recorded. Results The haemoglobin (Hb) level was significantly improved in patients treated with roxadustat combined with ESA after 1 month (7.8 ± 1.54 g/dL vs 8.96 ± 1.38 g/dL, p = 0.003), which was not found in patients treated with roxadustat alone (8.2 ± 1.28 g/dL vs 8.35 ± 1.54 g/dL, p = 0.652). Patients treated with roxadustat combined with ESA had a higher Hb response rate (47.4%) than those treated with roxadustat alone (15.8%) during the first month (p = 0.036). In addition, the level of serum iron was increased, and serum ferritin (SF) was decreased in both groups. Conclusion Roxadustat combined with ESA treatment might be more beneficial for improving renal anemia in MHD patients with ESA hyporesponsiveness during the first month of roxadustat therapy replacement.

The Efficacy and Safety of Roxadustat for the Treatment of Posttransplantation Anemia: A Randomized Study

IntroductionRoxadustat, an oral hypoxia-inducible factor prolyl hydroxylase inhibitor, can stimulate erythropoiesis. Our objective was to evaluate the efficacy and safety of roxadustat for the treatment of post-transplantation anemia (PTA). MethodsA total of 150 adult renal transplant recipients who underwent PTA were randomized to either the experimental group or the control group. During the 12-week randomized phase, the experimental group was randomized to oral iron and roxadustat treatment, and the control group was randomized to oral iron treatment only. The randomized phase was followed by a 12-week extended treatment period in which all participants were prescribed roxadustat treatment according to hemoglobin (Hb) levels. All the participants were followed up every 4 weeks. The primary endpoints were the change in Hb levels and response rate throughout the randomized period. ResultsA total of 128 participants completed the randomized treatment period (90 in the experimental group and 38 in the control group). The mean Hb concentration at week 12 was 12.20 g/dL in the experimental group and 11.19 g/dL in the control group. A significantly higher proportion of participants who achieved Hb responses were in the experimental group than in the control group. Differences in serum iron, total iron-binding capacity (TIBC) and transferrin from baseline to week 8-12 were significant between the two groups. The adverse event profiles were comparable between the two groups. ConclusionsRoxadustat increased Hb in adult renal transplant recipients who underwent PTA, with an adverse event profile comparable to that of the control group.

Daratumumab monotherapy in refractory warm autoimmune hemolytic anemia and cold agglutinin disease

AbstractAutoimmune hemolytic anemia (AIHA) is a rare autoantibody-mediated disease. For steroid and/or rituximab-refractory AIHA, there is no consensus on optimal treatment. Daratumumab, a monoclonal antibody targeting CD38, could be beneficial by suppression of CD38+ plasma cells and thus autoantibody secretion. In addition, because CD38 is also expressed by activated T cells, daratumumab may also act via immunomodulatory effects. We evaluated the efficacy and safety of daratumumab monotherapy in an international retrospective study including 19 adult patients with heavily pretreated refractory AIHA. In warm AIHA (wAIHA, n = 12), overall response was 50% with a median response duration of 5.5 months (range, 2-12), including ongoing response in 2 patients after 6 and 12 months. Of 6 nonresponders, 4 had Evans syndrome. In cold AIHA (cAIHA, n = 7) overall hemoglobin (Hb) response was 57%, with ongoing response in 3 of 7 patients. One additional patient with nonanemic cAIHA was treated for severe acrocyanosis and reached a clinical acrocyanosis response as well as a Hb increase. Of 6 patients with cAIHA with acrocyanosis, 4 had improved symptoms after daratumumab treatment. In 2 patients with wAIHA treated with daratumumab, in whom we prospectively collected blood samples, we found complete CD38+ T-cell depletion after daratumumab, as well as altered T-cell subset differentiation and a severely diminished capacity for cell activation and proliferation. Reappearance of CD38+ T cells coincided with disease relapse in 1 patient. In conclusion, our data show that daratumumab therapy may be a treatment option for refractory AIHA. The observed immunomodulatory effects that may contribute to the clinical response deserve further exploration.

Efficacy of ferric carboxymaltose or darbepoetin alfa for chemotherapy-induced anemia in patients with esophagogastric or pancreaticobiliary cancer: a retrospective comparative study.

Esophagogastric and pancreaticobiliary cancers are associated with chronic blood loss, poor nutrition, and surgical interventions that interfere with iron absorption. Patients with these cancers often have a higher incidence of chemotherapy-induced anemia (CIA) than patients with other malignancies. To investigate the efficacy of intravenous iron or erythropoietin-stimulating agents (ESA) for CIA treatment in patients with esophagogastric or pancreaticobiliary cancer. Retrospective, comparative chart review of patients with esophagogastric or pancreaticobiliary cancer who received ferric carboxymaltose (FCM), or darbepoetin alfa (DA), and myelosuppressive chemotherapy at Chungbuk National University Hospital between June 2018 and December 2022. To assess the efficacy of FCM or DA over time, data on hemoglobin (Hb) levels were collected from the time of administration of FCM or DA (baseline) until 6 months post-baseline, when available. In total, 214 patients (124 in the FCM and 90 in the DA group) were included in the analysis. The FCM group had a higher maximum Hb level and Hb changes for 3 months (mean ± standard deviation) following FCM or DA administration from baseline than the DA group (11.3 ± 1.5 versus 10.9 ± 1.2 g/dL, p = 0.02 and 2.0 ± 1.4 versus 1.5 ± 1.1 g/dL, p = 0.004, respectively). The FCM group had a higher proportion of Hb responders than the DA group (83.9% versus 68.9%, p = 0.013). Based on multivariable analysis, only the CIA treatment group was a significant factor for Hb response (odds ratio = 2.06, 95% confidence interval = 1.05-4.06, p = 0.036). Both FCM and DA are effective, and FCM showed a higher Hb response than DA for CIA treatment in patients with esophagogastric or pancreaticobiliary cancer. Therefore, further randomized controlled trials should determine the optimal treatment for CIA in patients with these cancers undergoing myelosuppressive chemotherapy.

Efficacy of roxadustat in maintenance hemodialysis patients with erythropoietin-hyporesponsive anemia.

To investigate the efficacy of roxadustat in hemodialysis patients with erythropoietin (EPO) hypo-responsive anemia. This retrospective study included 55 hemodialysis patients with erythropoietin hypo-responsive anemia at the First Affiliated Hospital of Chongqing Medical University from January to December 2020. We observed their hemoglobin (Hb) changes, inflammatory factors, and adverse reactions before and after 12 weeks of roxadustat treatment. Among the 55 patients, the average age was 60.75 ± 13.96 years old, and the median dialysis age was 48 months. All patients were taken off EPO and switched to roxadustat during the follow-up period. Compared with baseline, patients' Hb was significantly increased (90.64 ± 20.01 g/L, 98.52 ± 15.89 g/L, 104.34 ± 19.15 g/L, and 107.02 ± 20.54 g/L, respectively) (p &lt; 0.05). At 12 weeks of roxadustat treatment, 34 patients (61.82%) met the target Hb levels (100 - 130 g/L). The multivariate logistic analysis showed that Hb response positively correlated with the Hb level before roxadustat treatment (p = 0.046), while responding well to roxadustat negatively correlated with blood platelet-to-lymphocyte ratio (PLR) and duration of dialysis (p = 0.029 and p = 0.046) in patients with EPO hypo-responsive anemia. Roxadustat could effectively improve anemia; the PLR and dialysis age were independent predictors of roxadustat efficacy in dialysis patients with EPO hypo-responsive anemia.

Probiotic Supplement Enhances the Hematological Parameters and Immune Response of Common Carp against Fish Pathogen Aeromonas hydrophila

Probiotic bacteria play an important role in the growth and health of aquatic animals by improving their immune system. A 60-day experiment study was carried out to evaluate the effect of probiotic bacteria Bacillus subtilis dietary supplement enhances the hematological parameters and Immune response of fish Common carp against the pathogenic Aeromonas hydrophila. The experimental fish with an average mean weight of 15.15 ± 1.05 g were distributed randomly into 3 groups (Control (CTRL (Basal feed and without A. hydrophila), Exp1 (Basal feed and with A. hydrophila, and Exp2 (108 CFU/ml with probiotic supplement with A. hydrophila). On the 56th day, experimental groups were then challenged with A. hydrophila (1.0 × 107 CFU/mL), after 72 hrs of infection, blood samples were collected randomly from five fish from each group. Results showed that probiotic supplementation improved Hematological parameters such as RBCs, WBCs, Hb, PCV, and Immune response parameters (Nitroblue Tetrazolium Activity, aminotransferase, Serum lysozyme activity, total protein, and immunoglobulin). This present study suggests that the probiotic diet enhances the disease resistance against Aeromonas hydrophila in the culture of Common carp.

Predicting Hemoglobin Response to Hydroxyurea and Voxelotor in Adults with Sickle Cell Disease

Background: Chronic anemia contributes to morbidity and mortality in sickle cell disease (SCD) and is associated with stroke, leg ulcers, pulmonary hypertension (PH), priapism, and chronic kidney disease (CKD). Treatment options for anemia in SCD are limited - hydroxyurea (HU) is the gold standard treatment, but hemoglobin (Hb) responses to HU in adult and pediatric cohorts appear to be modest at best. We evaluated the Hb response to HU and voxelotor in an adult SCD cohort, as well as baseline factors associated with Hb response to HU. Methods: This longitudinal study was based on retrospective chart review of patients with SCD followed in the UPMC Adult Sickle Cell Program, with drug start dates between 2007 and May 2023. Subjects with a documented start date for HU/voxelotor, a baseline Hb ≤ 3 months prior to starting drug, and a follow-up Hb at 1 or 3 months (± 2 weeks) after the start date were included. Those who self-discontinued therapy were excluded. Baseline factors were collected within ≤ 3 months of drug start date. Given the small number of subjects on voxelotor, factors associated with Hb response were evaluated in the HU group only. Baseline factors were reported using descriptive statistics and compared between Hb responders (defined as Hb increase ≥ 1 g/dL from baseline - a common outcome measure in clinical trials of anti-polymerization agents) and non-responders. Linear regression analysis was performed with change in Hb at 1 month (ΔHb) as the outcome of interest, as Hb levels at 1 and 3 months were highly correlated (r=0.905, p&amp;lt;0.001) and there were fewer missing values for Hb at 1 month. Variables associated with ΔHb with p&amp;lt;0.25 were included in a multivariable regression model. P&amp;lt;0.05 was considered significant, and 95% confidence intervals (CI) were reported. Results: Out of 394 subjects, 93 met eligibility criteria, including 88 starting HU and 5 starting voxelotor. One subject in the voxelotor group was on stable-dose HU. Median ages at start of HU and voxelotor were 24.5 years (range 13-57) and 45.4 years (range 22-60), respectively. Females accounted for 50/88 (56.8%) HU subjects and 4/5 (80%) voxelotor subjects. HbSS genotype made up 47/88 (53.4%) of the HU group and 4/5 (80%) of the voxelotor group. Median baseline Hb in the HU group was 9.8 g/dL, with a median increase of 0.2 g/dL and 0.3 g/dL at 1 and 3 months, respectively. In contrast, baseline Hb in the voxelotor group was 7.2 g/dL with a median increase of 1.9 g/dL and 2.1 g/dL at 1 and 3 months, respectively. Hb response was observed in 21/88 (24%) subjects in the HU group vs. 4/5 (80%) subjects in the voxelotor group. Among responders, median Hb increase was 2.2 g/dL (1 month) and 2.0 g/dL (3 months) with HU. Median baseline ferritin was 200 ng/mL in the HU group and 2413 ng/mL in the voxelotor group. In the HU group, lower baseline Hb was associated with female sex, severe SCD genotype (HbSS, HbSβ 0), and higher HbS%, WBC count, platelet count, and hemolytic markers (lactate dehydrogenase, total bilirubin, and reticulocyte count) (data not shown). Demographic/clinical variables were not associated with Hb response, except for male gender at 3 months (Table 1). Lower baseline Hb, RBC count, and hematocrit and higher MCHC, HbS%, LDH, and total bilirubin were associated with positive Hb response at 3 months. HbF% was higher in the responder groups but was not significant. In a multivariable linear regression model including age, PH, leg ulcers, CKD, baseline Hb, platelets, and total bilirubin as explanatory variables, baseline Hb was negatively associated with ΔHb (B = -0.26, CI = -0.40 to -0.12, p&amp;lt;0.001). History of leg ulcers was also negatively associated with ΔHb but was not significant (B = -0.94, CI = -2.01 to 0.13, p=0.083). Conclusion: Overall, Hb response to HU was much lower compared to voxelotor, though in the 24% of subjects who responded to HU, the Hb increase was comparable. Though limited by small sample size, our data revealed that patients started on voxelotor vs. HU were older, more anemic, and more iron overloaded. Subjects with lower baseline Hb had a more robust Hb response to HU. While limited by the absence of dosing and adherence data, this study provides proof of concept of using baseline characteristics to predict Hb response to SCD therapies, demonstrating the feasibility of a personalized treatment approach in SCD. In addition, our data provide real-world evidence of the effectiveness of HU vs. voxelotor for chronic anemia in SCD.

Improvements in Markers of Hemolysis and Liver Iron Concentration in Mitapivat-Treated Adult Patients with a Delayed Hemoglobin Response

Background: Pyruvate kinase (PK) deficiency is a rare, hereditary disorder that leads to chronic hemolytic anemia and significant complications, including iron overload. Mitapivat is a first-in-class, oral, allosteric activator of PK, approved in the United States by the Food and Drug Administration for the treatment of hemolytic anemia in adults with PK deficiency, and in the European Union by the European Medicines Agency and in Great Britain by the Medicines and Healthcare products for the treatment of PK deficiency in adults. In the ACTIVATE trial (NCT03548220), mitapivat demonstrated improvements in hemoglobin (Hb) in patients (pts) who were not regularly transfused. 40% (16/40) of pts receiving mitapivat met the primary endpoint of Hb response (≥1.5 g/dL increase from baseline [BL] sustained at ≥2 scheduled assessments at Weeks [Wks] 16, 20, and 24 in the fixed-dose period) compared with 0 for placebo (PBO). In a post-hoc analysis, 3 pts who did not meet the protocol-defined endpoint in ACTIVATE later achieved Hb improvements ≥1.5 g/dL after the start of the fixed-dose period and into the long-term extension (LTE). Factors contributing to delayed improvements in Hb with mitapivat have not yet been explored, but in the setting of chronic hemolysis, iron overload may interfere with erythropoiesis and limit Hb response. Methods: In the global, phase 3, randomized, PBO-controlled ACTIVATE trial, 80 pts were randomized 1:1 to receive mitapivat or PBO for a 12-wk dose-optimization period (5/20/50 mg twice daily), followed by a 12-wk fixed-dose period. Pts who completed the ACTIVATE trial were eligible to continue into the LTE where all pts received mitapivat (pts randomized to PBO in ACTIVATE that received mitapivat in LTE completed a 12-wk dose-optimization period [5/20/50 mg twice daily] and then continued on optimized mitapivat dose). This analysis examined changes in markers of hemolysis and liver iron concentration (LIC) in pts who did not meet the protocol-defined endpoint (≥1.5 g/dL increase from BL sustained at ≥2 scheduled assessments at Wks 16, 20, and 24 in fixed-dose period), but achieved a delayed Hb response, defined as ≥1.5 g/dL increase from BL in Hb at least twice, with the 2nd improvement not occurring until the start of the LTE. Data for Hb and LIC are reported up until the last time point for which data were available for all pts. Results: A total of 6 pts (3 originally randomized to mitapivat and 3 originally randomized to PBO; all received mitapivat in the LTE) met the criteria for delayed Hb response which occurred between Wks 36 and 120 after the start of mitapivat treatment. Median (Q1,Q3) improvements from BL in Hb were 1.7 (1.3, 1.7) g/dL at Wk 60 (Figure 1). Five of 6 pts showed early improvements in hemolysis. Wk 12 median (Q1,Q3) change from BL in indirect bilirubin was -28.3 (-48.6, -18.5) µmol/L (Figure 1) and in reticulocyte percentage was -11.5 (-19.6, -3.7) %. Decreases in LIC occurred in 5 of 6 pts with median (Q1,Q3) change from BL in LIC of -1.3 (-2.0, -0.2) mg Fe/g dry weight at Wk 72 (measured every 24 wks). Two of 6 pts had BL LIC &amp;gt;5 mg Fe/g dry weight. Both pts (one on chelation) experienced improvements in LIC which corresponded with increases in Hb (Figure 2). Conclusion: Adult pts with PK deficiency who do not show early Hb improvements (≥1.5 g/dL) with mitapivat may still experience a delayed Hb response, generally preceded by improvements in hemolysis. In addition, pts with BL iron overload may experience decreases in LIC that correspond to increases in Hb. Improvements in hemolysis and LIC during mitapivat treatment may allow for an eventual Hb response when early Hb improvements ≥1.5 g/dL are not observed.

A Phase III Clinical Trial Program Investigating the Efficacy and Safety of Ianalumab in Patients with Primary Immune Thrombocytopenia (VAYHIT1 and VAYHIT2) and Warm Autoimmune Hemolytic Anemia (VAYHIA)

Background: Immune thrombocytopenia (ITP) and warm autoimmune hemolytic anemia (wAIHA) are characterized by autoantibody destruction of platelets and red blood cells, respectively. Autoreactive B cells play a role in the pathophysiology of ITP and wAIHA. Serum levels of B-cell activating factor (BAFF) are elevated in these disorders and correlate with increased disease activity. Ianalumab is a novel, fully human immunoglobulin G1 monoclonal antibody that targets BAFF receptor (BAFF-R) and has a unique dual mechanism of action: direct antibody-dependent cellular cytotoxicity-mediated B-cell depletion and inhibition of B-cell differentiation, proliferation and survival via blockade of BAFF-R-mediated signaling. Corticosteroids (CS) are the standard first-line treatment for ITP; however, few patients achieve a long-term response. Additionally, extended and recurrent use of CS is associated with substantial toxicity. Thrombopoietin receptor agonists (TPO-RAs), such as eltrombopag, are commonly used second-line ITP treatments and often achieve a response; however, responses are rarely maintained once treatment ends, so chronic administration is typically required. For wAIHA, few treatments have been approved, and patients rarely achieve durable responses on CS or off-label rituximab. Thus, there are significant unmet needs for patients with ITP or wAIHA. Aim: We report the designs of the randomized, double-blind, multicenter, 3-arm Phase III VAYHIT1 (NCT05653349), VAYHIT2 (NCT05653219) and VAYHIA (NCT05648968) trials. The trials aim to assess whether ianalumab, working with a distinct and complementary mechanism to standard-of-care treatments, can induce durable responses in patients with ITP or wAIHA. Trial designs: VAYHIT1 and VAYHIT2 will assess the efficacy and safety of ianalumab vs placebo in addition to first-line CS and short-term eltrombopag, respectively, in adults with primary ITP. In both trials, patients will be randomized 1:1:1 to intravenous (IV) low-dose ianalumab, high-dose ianalumab or placebo every 4 weeks (wks). The primary endpoint in both trials is the time from randomization to treatment failure, defined as platelet count &amp;lt;30 G/L later than 8 wks from randomization, need for rescue treatment later than 8 wks from randomization, start of a new ITP therapy, or death. In VAYHIT2, ineligibility to taper or inability to discontinue eltrombopag after the completion of treatment with ianalumab or placebo will also be assessed as treatment failure. Secondary endpoints include response rate, complete response rate and safety ( Table). VAYHIA will assess the efficacy and safety of ianalumab vs placebo in adults with wAIHA who have failed ≥1 treatment. Patients will be randomized 1:1:1 to IV low-dose ianalumab, high-dose ianalumab or placebo every 4 wks. Selected supportive care is allowed. The primary endpoint is durable hemoglobin (Hb) response, defined as Hb ≥10 g/dL and an Hb increase of ≥2 g/dL from baseline for ≥8 consecutive wks between Wk 9 and Wk 25 in the absence of rescue or prohibited treatment. The key secondary endpoint is duration of durable Hb response ( Table). An optional open-label crossover period will allow patients who receive placebo and do not achieve a durable Hb response to receive high-dose ianalumab. Patients from all 3 trials will be monitored for efficacy until treatment failure (or up to 39 months after the last patient was randomized, whichever comes first) and safety for up to 2 years. Conclusions: These trials have been designed based on the hypothesis that, when administered early in disease progression, medical therapy targeting complementary physiological pathways may restore self-tolerance in patients with ITP and wAIHA. Ianalumab in combination with standard of care is expected to safely induce a high response rate that will be maintained beyond treatment completion. Ianalumab may address the unmet needs for patients with ITP and wAIHA. Current status: At the time of writing, VAYHIT1, VAYHIT2 and VAYHIA are recruiting. The open-label, single-arm, Phase II VAYHIT3 trial is also assessing ianalumab in patients with primary ITP previously treated with at least 1 CS and 1 TPO-RA (NCT05885555).

A US Retrospective Observational Study of Rituximab Use in Cold Agglutinin Disease

Background Cold agglutinin disease (CAD) is a rare autoimmune hemolytic anemia (AIHA). Rituximab is approved for treatment of B-cell lymphoma and severe rheumatoid arthritis and used off-label as a treatment for AIHA, including CAD. There is limited real-world evidence on patterns of rituximab use, safety, response rate and duration of response among patients with CAD. Objectives The key objectives were: 1) to characterize patients who initiated rituximab and examine their treatment patterns; 2) to describe the incidence of serious infections (SIs) prior and post rituximab treatment; 3) to assess the rate and duration of response to rituximab using hemolytic markers. Methods This retrospective, cohort study included adult (aged ≥18 years) patients with CAD from Optum's de-identified Market Clarity Data (2007-2021). Patients with CAD (Cohort 1) were indexed on their CAD diagnosis date. Cohort 1 patients who had ≥1 rituximab infusion (Cohort 2) were indexed on their 1 st rituximab infusion date ( Figure 1). Patients with cold agglutinin syndrome associated comorbidities on or before their index date were excluded. For each cohort, demographics, and clinical characteristics at index date, and for Cohort 2, clinical characteristics during 1 year before index date were described. Data for rituximab treatment patterns included number of courses, treatment type (monotherapy or combination therapy), complete or incomplete course, and the use of blood transfusion (BT) as rescue therapy. In Cohort 2, the incidence rates of SIs per 1000 patient-years before and after treatment (within 6 months of 1 st infusion) were assessed. Response to treatment was assessed using hemolytic markers (hemoglobin [Hb], bilirubin, and lactate dehydrogenase [LDH]). From baseline, a change of ≥2 g/dL was considered a Hb response, while a decrease of 50% was assessed as proxy for a bilirubin or LDH response. Relapse was defined as the reversal of biomarker levels below the minimum response threshold. Response duration was the period from the date of response to that of relapse. Results A total of 611 CAD patients were identified (Cohort 1); 94 of them received rituximab (Cohort 2). Median time from CAD diagnosis to rituximab initiation was 43.5 (Interquartile range [IQR]: 13.0-308.3) days. Overall, Cohort 2 had a more severe disease status at treatment initiation than all patients with CAD (Cohort 1) at diagnosis (higher comorbidity scores, rates of health care resource utilization, lower Hb, and more severely elevated hemolytic markers; Table 1). In Cohort 2, the mean (SD) number of rituximab courses per patient was 1.45 (1.16); 24 (25.5%) of patients had ≥1 incomplete course; 37 (39.4%) required BT rescue therapy, and the median time from rituximab initiation to 1 st BT was 31 (IQR: 1.5-110.5) days. Combination therapy was rarely used (3/94; 0.03%); only 1 patient completed. The incidence rate (95% CI) of SIs (per 1000 patient-years) post CAD diagnosis in Cohort 2 was ~3 times higher in the 4 to 6 months after rituximab initiation (637.1 [242.2-1032.0]) than before (245.4 [125.1-365.6]). Proportion of corticosteroid use was the same during 1 year prior to rituximab initiation and concomitantly with rituximab (54/94; 57.4%, both). For patients in Cohort 2 with available data, 69.5% (41/59) had a Hb response, 59.6% (28/47) had a bilirubin response, and 31.3% (10/32) had a LDH response to the 1 st course of rituximab (median [IQR] time to response: 48.0 [33.5-85.0], 68.0 [33.3-199.8], and 67.5 [45.3-211.3] days, respectively). Among patients who responded to the 1 st course, Hb relapse occurred in 68.3% (28/41), bilirubin relapse in 53.6% (15/28), and LDH relapse in 80.0% (8/10) of patients (median [IQR] time from response to relapse: 44.0 [13.3-90.8], 98.00 [29.0-257.0], and 93.00 [21.3-161.8] days, respectively). Conclusions The findings highlight outcomes of rituximab use for treatment of CAD in a real-world setting. Patients who initiated rituximab had more severe disease compared to all patients with CAD. Rituximab was predominantly given as monotherapy, with an average of 1.45 courses per patient. About 25% of patients had ≥1 incomplete rituximab course, and rescue therapy with BTs was often required. Patients receiving rituximab experienced 3 times more SIs after initiating rituximab than before treatment. Although responses to rituximab were commonly observed, duration of response was short, and the rate of relapse was high.

A Phase 2/3, Double-Blind, Randomized, Placebo-Controlled, Multicenter Study of Mitapivat in Patients with Sickle Cell Disease: RISE UP Phase 2 Results

Background: Sickle cell disease (SCD) is characterized by the presence of hemoglobin S (HbS), a structural variant caused by a mutation in the HBB gene. Deoxygenated HbS molecules polymerize into “fibers”, causing red blood cells (RBCs) to sickle and hemolyze. Sickled RBCs have a shortened lifespan and impede blood flow to tissues, causing painful vaso-occlusive crises. Recurrent microvascular damage and chronic hemolytic anemia result in progressive multi-organ damage. Mitapivat is an oral, small-molecule allosteric activator of pyruvate kinase, a key enzyme in RBC metabolism, with a dual mechanism of action under investigation in SCD: it increases adenosine triphosphate (ATP) in RBCs, improving survival, and decreases 2,3−diphosphoglycerate, increasing Hb oxygen affinity and thus diminishing HbS polymerization and RBC sickling. RISE UP is a global Phase (Ph) 2/3 double-blind, randomized, placebo (PBO)-controlled trial evaluating the efficacy and safety of mitapivat in patients (pts) with SCD (NCT05031780). Methods: In the Ph 2 double-blind period (DBP), 2 dose levels of mitapivat were evaluated against PBO for 12 weeks (wks). Eligible pts were ≥16 years with ≥5.5 to ≤10.5 g/dL Hb and ≥2 to ≤10 sickle cell pain crises (SCPCs, including pain, priapism, acute chest syndrome, hepatic sequestration, and splenic sequestration) in year prior to entry. Pts were randomized 1:1:1 to mitapivat 50 mg twice daily (BID), mitapivat 100 mg BID, or matched PBO. Pts completing the DBP were eligible to receive mitapivat in a 216-wk open-label extension. Primary endpoints were Hb response (≥1.0 g/dL increase in average Hb concentrations from Wks 10 through 12 compared with baseline [BL], tested with Fisher's exact test at 2-sided 0.05 significance level) and adverse events (AEs), including the type, severity, and relationship to study drug. Prespecified secondary endpoints included average change from BL from Wks 10 through 12 in Hb, markers of hemolysis, markers of erythropoiesis, and pt-reported fatigue score, as well as annualized rate of SCPCs. Results: In the Ph 2 DBP, 79 pts were randomized and treated with mitapivat 50 mg BID (n=26), mitapivat 100 mg BID (n=26), or PBO (n=27). In the 50 mg BID, 100 mg BID, and PBO arms, mean (SD) age was: 29.9 (7.79), 30.2 (10.52), and 28.5 (10.30) years; female: 57.7%, 61.5%, and 74.1%; mean (SD) BL Hb: 8.76 (1.295), 8.82 (0.898), and 8.49 (1.141) g/dL; mean (SD) number of SCPCs during previous year: 3.1 (1.83), 3.2 (1.65), and 3.4 (1.91), respectively. The primary endpoint was achieved; 46.2% (12/26) of pts in the 50 mg BID arm and 50.0% (13/26) in the 100 mg BID arm demonstrated a significant increase in Hb response compared with 3.7% (1/27) of pts in the PBO arm (2-sided p=0.0003 and p=0.0001, respectively). Mitapivat was generally well tolerated; observed safety profile was consistent with previously reported data of mitapivat in SCD and other hemolytic anemias. No serious treatment-emergent AEs were related to study drug; no AEs led to study drug discontinuation or death. Least-squares mean (LSM [95% CI]) for average change from BL in Hb levels from Wks 10 through 12 was 1.11 (0.77, 1.45) g/dL, 1.13 (0.79, 1.47) g/dL, and 0.05 (−0.28, 0.39) g/dL for 50 mg BID, 100 mg BID, and PBO arms, respectively ( Figure). Improvements were observed in markers of hemolysis and erythropoiesis. SCPCs annualized rates (95% CI) were 0.83 (0.34, 1.99) and 0.51 (0.16, 1.59) for 50 mg BID and 100 mg BID arms, respectively, compared to 1.71 (0.95, 3.08) for PBO. LSM (95% CI) for average changes from BL in pt-reported fatigue score from Wks 10 through 12 was −3.80 (−7.16, −0.45), −0.10 (−3.27, 3.08), and −0.17 (−3.40, 3.07) for 50 mg BID, 100 mg BID, and PBO arms, respectively ( Table). Conclusion: During the Ph 2 DBP of RISE UP, treatment with mitapivat demonstrated statistically significant and clinically meaningful improvement in Hb response at both dose levels (50 mg BID and 100 mg BID) compared to PBO. Improvements in markers of hemolysis/erythropoiesis and annualized rate of SCPCs were observed for both doses as compared with PBO; the magnitude of improvement in markers of hemolysis and annualized rate of SCPCs was larger in the mitapivat 100 mg BID arm. Mitapivat was well tolerated with a safety profile consistent with previous studies. These data suggest that mitapivat, through its dual mechanism of action, may provide clinical benefit to pts with SCD and support continued development in the Ph 3 portion of the RISE UP trial.

Long-Term Safety and Efficacy of Mitapivat, an Oral Pyruvate Kinase Activator, in Adults with Sickle Cell Disease: Extension of a Phase 1 Dose Escalation Study

BACKGROUND In a Phase I study (NCT04000165, Xu et al, 2022), we showed that mitapivat, an investigational oral allosteric activator of pyruvate kinase (PK), demonstrated an acceptable safety and tolerability profile at multiple ascending dose levels in patients (pts) with sickle cell disease (SCD). We also established proof-of-concept for activating PK as a viable therapeutic approach; mitapivat decreased 2,3- diphosphoglycerate (2,3-DPG) and increased adenosine triphosphate (ATP) levels, improved hematologic parameters, and reduced sickling in pts with SCD (HbSS). In this extension study (NCT04610866), we evaluated the safety, tolerability and efficacy of mitapivat as a long-term maintenance therapy for pts with SCD. METHODS We enrolled 15 adult pts (age &amp;gt;18 years) with confirmed SCD (HbSS) and baseline hemoglobin (Hb) 7.1 - 10.5 g/dL, with no recent blood transfusions, erythropoietin therapy, or changes in SCD-specific therapies including hydroxyurea (HU) and L-glutamine. Thirteen pts had participated in the Phase 1 study and 2 pts were mitapivat naïve. All pts started mitapivat at 50 mg twice daily (BID), escalating after 4 weeks (wks) to 100 mg BID, unless a rapid Hb rise was observed (increase of ≥2 g/dL), the maximum Hb level of 12.5 g/dL had been reached, or per PI discretion. Patients continued on this maintenance dose of mitapivat through the end of the study. Dose reductions were performed at any time during the extension phase for safety and tolerability. After completion of the 24-wk core period, pts had an option to continue on mitapivat treatment in the extension period for up to 6 years. Study visits were conducted every 2 wks (x2), 4 wks (x2), and then every 12 wks for first 2 years (yrs) and will continue every 6 months for the remaining 4 yrs. The extension period of the study is ongoing; here we report data for up to 2 years (data cutoff March 23, 2023). Any and all vaso-occlusive crises (VOCs) that occurred while on study, regardless of attribution, were considered adverse events. RESULTS Of the 15 pts who completed the core period, 14 entered the extension study with 1 pt on 5 mg BID, 1 pt on 50 mg BID, 3 alternating between 50 and 100 mg BID, and the rest on 100 mg BID. Mean age of the 15 pts was 39 yrs (range: 25-57 yrs); 10 were male, and 11 were on HU. As of the cut-off date, median duration of mitapivat treatment for pts who entered the extension period was 84 wks (range: 48-108 wks), 1 pt discontinued after 2 yrs (pt decision) and 10 pts received 72 wks or more of treatment (Table 1) with a total of 1080 pt-wks of drug exposure thus far. Mitapivat was generally well tolerated; no treatment emergent adverse events (TEAEs) resulted in discontinuation of study drug or death during the extension period. The most common TEAEs (reported in 5 or more pts) were VOCs (n=8), estrone decrease (n=7), testosterone increase (n=6) and cough (n = 5); changes in laboratory values were not clinically significant. The most common serious TEAEs (reported in 2 or more pts) were VOCs (n=8) and lung infection (n = 2). Two pts experienced VOCs that were assessed as possibly drug-related (1 during drug escalation, and 1 during drug taper). All VOCs occurred in the setting of known VOC triggers. Three pts required dose reduction, 1 each secondary to pruritis, bloating and insomnia, respectively. In the latter 2 cases, the doses were subsequently increased to 100 mg BID, as TEAEs resolved. Other serious TEAEs were not considered related to study drug. The mean Hb at 24 wks increased significantly from baseline (mean: 1.38 g/dL, SD: 0.88 g/dL; p&amp;lt;0.0001), a result generally upheld at other follow-up periods (Fig. 1). 14/15 (93%) of the pts achieved a Hb response, defined as a ≥ 1 g/dL increase in Hb at any timepoint within the core period, compared to baseline. Improvements in Hb achieved in the core period were accompanied by improvements in markers of hemolysis, oxygen affinity (p50), sickling kinetics (t50), decreases in 2,3-DPG and increases in ATP levels, and were sustained in the extension study (Fig. 1 and 2). Concurrently, there were also improvements in red cell deformability (LORRCA) (Lundt et al, 2022) and trends in improvements in cardiopulmonary status (not shown). CONCLUSION Long-term use of mitapivat is safe and well tolerated in pts with SCD with evidence of sustained long-term improvements in Hb, hemolytic and sickling kinetics. Mitapivat offers a novel disease-modifying approach.

Preliminary Results from a Multicenter Phase 2/3 Study of Next-Generation HbS Polymerization Inhibitor GBT021601 for the Treatment of Patients with Sickle Cell Disease

Introduction: Sickle cell disease (SCD) is a lifelong inherited disorder resulting in polymerization of sickle hemoglobin (HbS) and is characterized by chronic hemolytic anemia, vaso-occlusive crises (VOCs), and cumulative end-organ damage. Voxelotor is a first-in-class HbS polymerization inhibitor approved in the US for the treatment of patients with SCD aged ≥4 years and in Europe for the treatment of hemolytic anemia due to SCD in patients aged ≥12 years. GBT021601 is a next-generation HbS polymerization inhibitor with improved pharmacokinetic (PK) properties that increases hemoglobin (Hb)-oxygen affinity and stabilizes Hb in the oxygenated state to inhibit polymerization. GBT021601 has the potential for higher Hb occupancies at lower doses than voxelotor and could potentially reduce treatment burden and improve clinical outcomes. Here we report preliminary safety, efficacy, and pharmacodynamic (PD) data from an ongoing phase 2/3 study of orally administered GBT021601 (NCT05431088) in patients with SCD. Methods: This is a 3-part, multicenter phase 2/3 study in SCD. Part A is a randomized, open-label, 12-week, dose-finding study of GBT021601 in adult participants. Part B is a placebo-controlled study in adult and adolescent participants. Part C is an open-label study in pediatric participants. Here, we report data at Week 12 from Part A, which enrolled participants aged 18-65 years with SCD (HbSS/HbSβ 0 genotype) and Hb 5.5-10.5 g/dL at screening. Eligible participants were randomly assigned 1:1 to GBT021601 100 mg or 150 mg and received a loading dose twice daily for 4 days followed by once-daily maintenance doses through to Week 12. The primary endpoint was change from baseline in Hb at Week 12; secondary endpoints included Hb response (increase from baseline &amp;gt;1 g/dL) and change from baseline in hemolysis markers at Week 12, PK, PD, and safety. Vascular cell adhesion molecule-1 (VCAM-1) levels are elevated during VOCs, with flow adhesion of whole blood on VCAM-1 previously reported as a prognostic biomarker for VOC risk. The effect of GBT021601 on adherent cells was evaluated using a microfluidic device coated with VCAM-1. Results: At data cutoff (June 20, 2023), 35 patients were treated in Part A; 28 had completed 12 weeks of treatment. The 100-mg group consisted of 17/35 patients (48.6%), with a mean (range) age of 29.1 (18-49) years; 7/17 patients (41.2%) were on hydroxyurea (HU). The 150-mg group had 18/35 patients (51.4%), with a mean (range) age of 30.2 (18-59) years; 9/18 patients (50.0%) were on HU. Most patients (32/35 [91.4%]) had the HbSS genotype. After 12 weeks of treatment, the mean (SD) increase in Hb from baseline was 2.67 (1.52) g/dL for the 100-mg group (n=12) and 3.17 (1.82) g/dL for the 150-mg group (n=11). A favorable trend towards reduction from baseline was observed in markers of hemolysis. Flow adhesion data showed patients taking GBT021601 had a reduction in adherent cells, which could correlate with a reduction in the probability of a VOC event (Figure). At data cutoff, the safety data showed GBT021601 was well tolerated. For 27 patients with ≥1 VOC at baseline, the baseline annualized VOC rate was 2.30 (95% CI 1.81-2.92), and the on-study annualized VOC rate was 1.16 (95% CI 0.55-2.43) with a median (range) on-study duration of 0.4 (0.03-0.41) years. Treatment-emergent adverse events (TEAEs), predominantly grade 1 and 2 (15/35 [42.9%]) and unrelated to treatment (14/35 [40.0%]), were reported for 22 patients (62.9%). Treatment-related TEAEs in 8/35 patients (22.9%) were headache (n=4), diarrhea (n=2), and abdominal discomfort, nausea, suspected seizure (uncoded), sickle cell anemia with crisis, upper abdominal pain, and urticaria (n=1 each). There was 1 TEAE, unrelated to treatment, that led to study discontinuation (sepsis, in the 100-mg group). One death deemed unrelated to GBT021601 was due to a cerebrovascular (CVA) event, in a patient with history of CVA and seizures, after new onset high fever and no change from baseline Hb 8.0 g/dL. Conclusions: Loading and daily doses of GBT021601 for 12 weeks were well tolerated in adult participants with SCD. Despite large increases in mean Hb levels, pain episodes did not increase and there was a reduction of adherent cells in a flow adhesion assay with VCAM-1, a potential biomarker for VOC risk. Data from Part A of this phase 2/3 study support the ongoing clinical development of GBT021601 as a potential treatment for individuals with SCD.

Real-World Experience of Individuals with Sickle Cell Disease Treated with Voxelotor: Initial Report from the Multicenter, Prospective Prospect Study

Introduction: Sickle cell disease (SCD) is an inherited blood disorder in which sickle hemoglobin (HbS) polymerization results in red blood cell sickling, which in turn leads to chronic hemolytic anemia, unpredictable pain episodes, and recurrent vaso-occlusive crises (VOCs). Hemolysis and low hemoglobin (Hb) are associated with organ damage, increased morbidity, and early mortality. Voxelotor, a first-in-class HbS polymerization inhibitor, is approved in the US for the treatment of patients with SCD aged ≥4 years and in Europe for the treatment of hemolytic anemia due to SCD in patients aged ≥12 years. In the phase 3, randomized, controlled HOPE (NCT03036813) and the phase 2, open-label HOPE-KIDS 1 (NCT02850406) trials, patients treated with once daily oral voxelotor experienced increased Hb levels and reductions in markers of hemolysis at Week 24 compared with baseline. Here we report the first efficacy and safety data from patients with SCD enrolled in the prospective PROSPECT registry who received voxelotor in a real-world setting. Methods: PROSPECT (NCT04930445) is a post-marketing, open-label, observational, prospective patient registry of patients with SCD (aged ≥4 years) in the US. Eligible participants are being treated with voxelotor as prescribed by their physician as part of their usual care. Participants are treated and evaluated per standard of care and at the physician's discretion. Treatment, including interruptions and restarting treatment, continue at the discretion of the treating physician. Patients receive any additional medications or transfusions as determined and prescribed by their physician. Follow-up duration is 5 years after the first dose of voxelotor therapy. Study data are collected from patient medical records and secondary data sources and entered in case report forms via an electronic data capture system. Results: At data cutoff (May 30, 2023), 85 patients were enrolled at 5 sites. The mean (SD) age was 33.2 (15.3) years, 51.8% of patients were female, and most (92.9%) were Black or African American. Overall, 72.9% of patients were genotype HbSS, 62.4% were taking concurrent hydroxyurea, and mean (SD) Hb at baseline was 7.7 (1.53) g/dL. The mean (SD) duration of treatment, excluding gaps, was 47.0 (12.35) weeks. At the data cutoff, 76 patients (89.4%) continued voxelotor treatment; 7 patients (8.2%) never started voxelotor, and 2 patients (2.4%) discontinued treatment because of adverse events (AEs).The initial prescribed daily doses of voxelotor were 1500 mg (84.7%), 1000 mg (8.2%), 900 mg (4.7%), or 500 mg (2.4%). The most common reasons for prescribing voxelotor were to reduce either anemia (74.1%), frequency of VOCs (15.3%), pain (14.1%), or the frequency of blood transfusion (9.4%); multiple reasons could be selected. In 66 patients with recorded baseline and posttreatment Hb values, the observed mean (SD) peak posttreatment Hb value was 9.0 (1.75) g/dL, representing a mean (SD) increase from baseline of 1.3 (1.25) g/dL. The range of peak Hb change from baseline was −1.4 to 4.6 g/dL and 52/66 patients (78.8%) had a positive Hb response (Figure). Reductions in markers of hemolysis were also observed following voxelotor treatment, with nadir mean (SD) decreases from baseline of −23.9% (55.92%) in reticulocyte percentage (n=54), −1.8 (2.36) mg/dL in total bilirubin (n=61), and −1.6 (1.95) mg/dL in indirect bilirubin (n=38). AEs of special interest reported in &amp;gt;3% of patients included diarrhea, headache, nausea, abdominal pain, and rash (Table); most of these AEs were mild or moderate in severity. Conclusions: PROSPECT is the first prospective patient registry of voxelotor, with the potential to follow up to 1000 participants for up to 5 years and enable long-term, robust data collection of real-world care patterns that could inform how best to incorporate voxelotor into the treatment paradigm of patients with SCD. In this initial cohort of participants enrolled to date, following voxelotor treatment for a mean duration of 47.0 weeks, the mean peak increase from baseline in Hb was 1.3 g/dL, and associated reductions in markers of hemolysis were observed. Safety data were consistent with the phase 3 HOPE and HOPE-KIDS 1 trials. Overall, these initial findings provide support for the real-world safety, tolerability, and effectiveness of voxelotor treatment in individuals with SCD. While enrollment is ongoing, updated data will be regularly reported.