Safety and efficacy results of switch from imiglucerase to velaglucerase alfa treatment in patients with type 1 Gaucher disease

Gaucher disease (GD) is a lysosomal storage disorder; symptomatic patients with type 1 GD need long‐term disease‐specific therapy of which the standard of care has been enzyme replacement therapy (ERT). Thirty‐eight of 40 patients (aged 9–71 years) clinically stable on ERT with imiglucerase, safely switched to a comparable dose of velaglucerase alfa (units/kg) during TKT034, a 12‐month, open‐label clinical study, and for 10–50 months in an extension study. The most common adverse events (AEs) judged to be drug‐related in the extension were fatigue and bone pain. No drug‐related serious AEs were reported. No AEs led to study withdrawal. At 24 months from baseline (baseline being TKT034 week 0), patients had generally stable hemoglobin, platelet, spleen, liver, and bone density parameters. Nevertheless, dose adjustment based on the achievement of therapeutic goals was permitted, and 10 patients, including seven patients who had platelet counts <100 × 10⁹/L at baseline, were given at least one 15 U/kg‐dose increase during the extension. Trends indicative of improvement in platelet count and spleen volume, and decreasing levels of GD biomarkers, chitotriosidase and CCL18, were observed. Immunogenicity was seen in one patient positive for anti‐imiglucerase antibodies at baseline. This patient tested positive for anti‐velaglucerase alfa antibodies in TKT034, with low antibody concentrations, and throughout the extension study; however, the patient continued to receive velaglucerase alfa without clinical deterioration. In conclusion, clinically stable patients can be switched from imiglucerase to velaglucerase alfa ERT and maintain or achieve good therapeutic outcomes. Am. J. Hematol. 90:592–597, 2015. © 2015 Wiley Periodicals, Inc.     

Enzyme replacement therapy with taliglucerase alfa: 36‐month safety and efficacy results in adult patients with Gaucher disease previously treated with imiglucerase

Taliglucerase alfa is the first available plant cell‐expressed human recombinant therapeutic protein. It is indicated for treatment of patients with type 1 Gaucher disease (GD) in adult and pediatric patients in several countries. Study PB‐06‐002 examined the safety and efficacy of taliglucerase alfa for 9 months in patients who previously received imiglucerase. The results of adult patients from Study PB‐06‐002 who continued receiving taliglucerase alfa in extension Study PB‐06‐003 for up to 36 months are reported here. Eighteen patients received at least one dose of taliglucerase alfa in Study PB‐06‐003; 10 patients completed 36 total months of therapy, and four patients who transitioned to commercial drug completed 30–33 months of treatment. In patients who completed 36 total months of treatment, mean percent (±standard error) changes from baseline/time of switch to taliglucerase alfa to 36 months were as follows: hemoglobin concentration, ?1.0% (±1.9%; n = 10); platelet count, +9.3% (±9.8%; n = 10); spleen volume measured in multiples of normal (MN), ?19.8% (±9.9%; n = 7); liver volume measured in MN, +0.9% (±5.4%; n = 8); chitotriosidase activity, ?51.5% (±8.1%; n = 10); and CCL18 concentration, ?36.5 (±8.0%; n = 10). Four patients developed antidrug antibodies, including one with evidence of neutralizing activity in vitro. All treatment‐related adverse events were mild or moderate and transient. The 36‐month results of switching from imiglucerase to taliglucerase alfa treatment in adults with GD provide further data on the clinical safety and efficacy of taliglucerase alfa beyond the initial 9 months of the original study. www.clinicaltrials.gov identifier NCT00705939. Am. J. Hematol. 91:661–665, 2016. © 2016 Wiley Periodicals, Inc.     

Velaglucerase alfa enzyme replacement therapy compared with imiglucerase in patients with Gaucher disease

Enzyme replacement therapy for Gaucher disease (GD) has been available since 1991. This study compared the efficacy and safety of velaglucerase alfa with imiglucerase, the previous standard of care. A 9‐month, global, randomized, double‐blind, non‐inferiority study compared velaglucerase alfa with imiglucerase (60 U/kg every other week) in treatment‐naïve patients aged 3–73 years with anemia and either thrombocytopenia or organomegaly. The primary endpoint was the difference between groups in mean change from baseline to 9 months in hemoglobin concentration. 35 patients were randomized: 34 received study drug (intent‐to‐treat: 17 per arm), 20 were splenectomized. Baseline characteristics were similar in the two groups. The per‐protocol population included 15 patients per arm. The mean treatment difference for hemoglobin concentration from baseline to 9 months (velaglucerase alfa minus imiglucerase) was 0.14 and 0.16 g/dL in the intent‐to‐treat and per‐protocol populations, respectively. The lower bound of the 97.5% one‐sided confidence interval in both populations lay within the pre‐defined non‐inferiority margin of ?1.0 g/dL, confirming that velaglucerase alfa is non‐inferior to imiglucerase. There were no statistically significant differences in the secondary endpoints. Most adverse events were mild to moderate. No patient receiving velaglucerase alfa developed antibodies to either drug, whereas four patients (23.5%) receiving imiglucerase developed IgG antibodies to imiglucerase, which were cross‐reactive with velaglucerase alfa in one patient. This study demonstrates the efficacy and safety of velaglucerase alfa compared with imiglucerase in adult and pediatric patients with GD clinically characterized as Type 1. Differences in immunogenicity were also observed. Am. J. Hematol. 88:179–184, 2013. © 2012 Wiley Periodicals, Inc.     

Early achievement and maintenance of the therapeutic goals using velaglucerase alfa in type 1 Gaucher disease

IntroductionTherapeutic goals have been described to monitor achievement, maintenance and continuity of therapeutic response in patients with type 1 Gaucher disease receiving enzyme replacement therapy.AimTo benchmark the impact of velaglucerase alfa treatment against therapeutic goals for 5 key clinical parameters of type 1 Gaucher disease (anemia, thrombocytopenia, hepatomegaly, splenomegaly and skeletal pathology).MethodsIn an open-label Phase I/II study, twelve adults with symptomatic type 1 Gaucher disease and intact spleens received velaglucerase alfa for 9 months (60 U/kg infusion every other week [EOW]). Eleven patients completed the study and 10 enrolled in a long-term extension. After 1 year, patients who achieved ≥ 2 hematological or organ goals began step-wise dose reduction from 60 to 45 then 30 U/kg EOW. Data for anemia, thrombocytopenia, hepatomegaly, splenomegaly and skeletal pathology at baseline and 4 years are available for 8 patients (3 male, 5 female). The proportion of patients at goal for anemia, thrombocytopenia, hepatomegaly and splenomegaly at baseline was compared with the proportion achieving each goal at 4 years. The proportion achieving the skeletal pathology goal was determined on the basis of Z-score improvement from baseline to 4 years. The proportion of patients who achieved all 5 goals at 4 years was compared with the proportion at goal for all 5 parameters at baseline.ResultsAt baseline, no patient was at goal for all clinical parameters. After 1 year of treatment, all patients maintained goals present at baseline, and all achieved ≥ 2 goals. All 8 patients began step-wise dose reduction from 60 to 30 U/kg EOW between 15 and 18 months. By year 4 of treatment, all patients met goals for all 5 clinical parameters; therefore 100% achievement was seen for each of the 5 long-term, therapeutic goals.DiscussionIn this velaglucerase alfa Phase I/II and extension study, clinically meaningful achievement of each long-term, therapeutic goal was observed for each patient, despite dose reduction after 1 year. This is the first report of a cohort where all patients receiving ERT for type 1 Gaucher disease achieved all 5 of these long-term, therapeutic goals within 4 years of starting treatment and after ≥ 2 years dose reduction.     

Seven‐year safety and efficacy with velaglucerase alfa for treatment‐naïve adult patients with type 1 Gaucher disease

Velaglucerase alfa is a human β‐glucocerebrosidase approved for Gaucher disease type 1 (GD1) treatment. This report summarizes the 7‐year experience of the now‐completed phase I/II and extension studies of adult GD1 patients who received velaglucerase alfa. Ten patients who completed the 9‐month, phase I/II study entered the extension trial TKT025EXT, of which eight completed this study. Doses were reduced after a cumulative treatment period of 15 to 18 months. Although all patients experienced ≥1 adverse event, no patient withdrew due to a drug‐related adverse event or required premedication. No patient developed anti‐drug antibodies, compliance remained high (median 98%), and seven of eight eligible patients transitioned to home infusions under supervision by healthcare professionals. Statistically significant improvements were observed for efficacy parameters: mean percentage changes from baseline (95% confidence intervals) were 18% (12%, 24%) for hemoglobin concentration, 115% (66%, 164%) for platelet counts, and ?42% (?53%, ?31%) and ?78% (?94%, ?62%) for liver and spleen volumes, respectively. Improvements were also observed for secondary endpoints chitotriosidase and CCL18 levels and exploratory endpoints (bone mineral density [BMD], bone marrow burden [BMB] scores). Normalization to near‐normalization of individuals' hemoglobin concentrations, platelet counts, liver volumes, and BMB scores was observed, and there were marked improvements in spleen volumes, biomarkers, and BMD. TKT025EXT represents the longest, prospective clinical trial for GD1 treatment to date and suggests that, despite dose reduction within 18 months of initiating therapy, velaglucerase alfa was generally well tolerated and was associated with marked improvement, including near normalization and/or normalization of key GD1 disease parameters. Am. J. Hematol. 90:577–583, 2015. © 2015 The Authors. American Journal of Hematology published by Wiley Periodicals, Inc.     

Effects of switching from a reduced dose imiglucerase to velaglucerase in type 1 Gaucher disease: clinical and biochemical outcomes

This paper describes the effects of a switch to velaglucerase alfa in a group of adult patients with type 1 Gaucher disease, all of whom had previously had their dose reduced as a consequence of the worldwide imiglucerase shortage. Thirty-two patients from two large European Gaucher centers switched to treatment with velaglucerase alfa after 1-8.5 months of dose reduction. The course of important Gaucher disease parameters was studied at four time points: one year before the shortage, just before the shortage, before a switch to velaglucerase and after up to one year of treatment with velaglucerase. These parameters included hemoglobin concentration, platelet count, plasma chitotriosidase activity in all patients, and spleen and liver volumes (as well as bone marrow fat fraction images) in 10 patients. Decreases in platelet counts as a result of reduced treatment with imiglucerase were quickly restored on treatment with velaglucerase alfa. Chitotriosidase activity declined overall after switching. Five out of 10 patients had an increase in liver volume of at least 10% after six months of velaglucerase treatment, which was reversible in 3. Most patients received infusions at home and no important side effects were observed. Velaglucerase alfa appears to be a safe and effective alternative for imiglucerase.Key words: velaglucerase alfa, type 1 Gaucher disease, platelet count     

Significant and continuous improvement in bone mineral density among type 1 Gaucher disease patients treated with velaglucerase alfa: 69-month experience, including dose reduction

Since bone pathology is a major concern in type 1 Gaucher disease (GD1), we evaluated bone mineral density (BMD) in adults receiving velaglucerase alfa in the seminal Phase I/II and extension trial. Ten treatment-na?ve symptomatic patients with GD1 (four men, six women; median age 35years, range 18-62years) were included; of these, four patients were receiving bisphosphonates at enrollment. Using WHO criteria to classify the lumbar spine (LS) and femoral neck (FN) BMD T-scores, respectively, one (10%) and four (40%) patients had osteoporosis; eight (80%) and five (50%) had osteopenia; and one each (10%) was in the normal range, at baseline. By Month 69, two LS and one FN osteopenic patients normalized and one FN osteoporotic patient became osteopenic; change was seen only in patients not receiving bisphosphonates. Significant improvements in BMD Z-scores were seen at the LS by Month 24 and at the FN by Month 33 and were continuous thereafter. In linear mixed models, Z-scores were significantly lower than the reference population at baseline and improved significantly with treatment (LS and FN both P<0.01); analysis of the subgroup of patients not receiving bisphosphonates showed similar results. In conclusion, in this small cohort, velaglucerase alfa was associated with clinically meaningful and statistically significant LS and FN BMD improvements as early as Month 24 (LS) and 33 (FN), despite dose reduction and significant baseline skeletal pathology. These results suggest that velaglucerase alfa may hold promise in the management of skeletal pathology associated with GD1.     

A benchmark analysis of the achievement of therapeutic goals for type 1 Gaucher disease patients treated with imiglucerase

To assess the extent to which patients with type 1 Gaucher disease (GD1) receiving individualized enzyme replacement therapy with imiglucerase attain six defined therapeutic goals. One hundred and ninety-five GD1 patients enrolled in the ICGG Gaucher Registry, all of whom had data available for hemoglobin, platelet count, liver volume, spleen volume, bone pain, and bone crises at first infusion and after 4 years of therapy with imiglucerase, were evaluated for achievement of published therapeutic goals. The proportion of patients who met all six therapeutic goals increased from 2.1% at first infusion to 41.5% at 4 years; > or =5 goals from 12.8% to 76.9%; > or =4 goals from 37.4% to 92.8%; > or =3 goals from 70.8% to 99.0%; and > or =2 goals from 95.4% to 99.5%. All patients met at least one goal at first infusion and after 4 years of treatment. The proportion of patients meeting specific therapeutic goals increased for all parameters between first infusion and 4 years of therapy: platelet count (24.6%-79.5%), spleen volume (25.6%-78.5%), liver volume (45.6%-90.8%), bone pain (62.6-70.3%), hemoglobin (68.2-91.8%), and bone crises (91.8-99.0%). On average, patients who received higher doses of imiglucerase achieved a greater number of therapeutic goals. This analysis provides a benchmark for evaluating the utility of a disease management approach for GD1 based on monitoring achievement of therapeutic goals after treatment with imiglucerase.     

Taliglucerase alfa leads to favorable bone marrow responses in patients with type I Gaucher disease

Taliglucerase alfa (Protalix Biotherapeutics, Israel) is a carrot-cell-expressed recombinant human beta-glucocerebrosidase recently approved in the United States for the treatment of type 1 Gaucher disease (GD). As bone disease is one of the most debilitating features of GD, quantification of bone marrow involvement is important for monitoring the response to treatment. Therefore, bone marrow fat fraction (Ff) measured by quantitative chemical shift imaging (QCSI) was included as exploratory parameter to evaluate bone marrow response in treatment naïve GD patients participating in a double-blind, randomized phase III study.Eight GD patients with intact spleens were treated with 30 or 60 U/kg biweekly. Ff results were compared to outcomes in 15 untreated Dutch GD patients with a follow-up interval of 1 year.Five taliglucerase alfa treated patients had a Ff below the threshold that relates to complication risk (< 0.23) at baseline (median (n = 8) 0.19, range 0.11–0.35). Ff significantly increased compared to baseline (p = 0.012) and compared to untreated patients (p = 0.005), already after 1 year of follow-up with further improvement up to 36 months. In four patients with the lowest Ff, the higher dose resulted in increases above 0.23 within 1 year. All patients had sustained improvements in all other parameters. There was no influence of antibodies on response parameters.Treatment with taliglucerase alfa results in significant increases in lumbar spine fat fractions, which indicates clearance of Gaucher cells from the bone marrow.     

Evaluation of Spanish Gaucher disease patients after a 6-month imiglucerase shortage

Recently, an acute restriction of imiglucerase has occurred as a result of viral contamination and manufacturing problems. A position statement from the European Working Group for Gaucher Disease and European Gaucher Alliance established a set of key recommendations for identifying and monitoring at-risk patients. In Spain, a profile of the shortage situation was obtained through follow-up of patients with Gaucher disease (GD) and compliance with the therapy recommendations. Here we describe a group of patients, with modified doses of imiglucerase, during the shortage. Fifty adult GD1 patients (25 males/25 females), previously on ERT, were analysed before and after the 6-month shortage. The mean age was 45.3 ± 15.3 years (range: 18-84). The mean Severity Score Index at diagnosis was 8.7 ± 3.8 (range: 3-19); 20% of patients were splenectomized; and 78% had bone disease. During the shortage, 23 patients (46%) discontinued therapy; as complications in this group only one patient suffered a bone crisis and another anaemia (Hb <10.0 g/dL). The mean reduction of haemoglobin level (-2.7%) and platelet counts (-5.4%) were non-significant. Chitotriosidase (CT) activity was increased 135% (p<0.03) and CCL18/PARC 8.2% (p<0.08) in this group. Imiglucerase was reduced by 50% in 17 patients (34%) in this group, seven patients (41.0%) suffered bone pain, three of them true bone crisis and four (23.5%) required support therapy. The mean reduction of haemoglobin (-2.8%) and platelet counts (-10.7%), CT activity was increased 48.2% (p<0.03) and no changes were observed in CCL18/PARC concentration. In both groups no significant changes in visceral size were observed. In 3 patients (6%), imiglucerase was reduced 75% and 7 patients (14%) needed to switch to another ERT (4 patients) or miglustat (3 patients) due to a restart of symptomatic disease. In Spain the 6 first months shortage of imiglucerase have produced a 20% incidence of bone pain, one case of anaemia, and a significant increase in CT activity. Fourteen percent of patients had to switch to another therapy. No significant changes in blood counts, visceral volumes and CCL18/PARC concentration were observed.     

Baseline characteristics and outcome in Romanian patients with Gaucher disease type 1

Background/aimTo present clinical and genetic characteristics of all Romanian patients with Gaucher disease type 1, in whom specific diagnosis has been confirmed by enzymatic and molecular methods and to analyze their outcome with and without enzymatic replacement therapy (ERT).Patients, methodsThere are fifty patients (F/M — 1.63/1) with Gaucher disease type 1. Clinical status, haemoglobin, thrombocytes, hepatic/splenic volume, bone mineral density and severity score were assessed at baseline and every six months thereafter. Thirty-nine patients (78%) received imiglucerase (44.4 ± 13.6 U/kg/2 weeks) for 3.1 +/? 1.4 years.ResultsBased on general prevalence data, our group represents 22.7% of the expected total number of patients with Gaucher disease type 1 in Romania. Mean age was 15.5 years at clinical onset and 28.9 years at confirmation of diagnosis. The genotype N370S/L444P was frequent in our group (35.9% of alleles). Anaemia, thrombocytopenia, splenomegaly and bone disease were present at 38%, 70%, 100% and 84%, respectively.Mean values for haemoglobin, thrombocytes, hepatic volume and chitotriosidase normalized after 0.5, 1.5, 2.5 and 3 years of ERT, respectively. Splenomegaly regressed from 14.4 × N (normal) to 3.06 × N over four years of treatment. Bone disease was ameliorated under ERT, yet bone mineral density worsened in patients treated with 30 U/kg/2 weeks.ConclusionsThe genotype N370S/L444P is frequent in our patients, in line with the severe phenotypes. ERT improved haematological parameters and visceromegaly, without a clear benefit for bone mineral density. To attain therapeutic goals, an early treatment start with optimal dosage is mandatory.     

Severe skeletal complications in Japanese patients with type 1 Gaucher disease

To better characterize skeletal complications in Japanese patients with type 1 Gaucher disease (GD), we performed genotyping and clinical and radiological analysis of 35 patients, the vast majority of this population, Skeletal complications tend to be very common, severe and rapidly progressive in Japanese patients with type 1 GD. Twenty (57%) of these patients manifested end points of severe bone disease including avascular necrosis, pathological fracture and/or bone crisis. Mean time from presentation/diagnosis of GD until presentation of this involvement was 3 years 6 months±4 years 1 month. Prevalence of severe bone disease is significantly higher in splenectomized than in non-splenectomized patients – 81% (17/21) versus 21% (3/14) (p=0.0007, Fisher's exact test). Four (29%) of 14 patients receiving enzyme replacement therapy (ERT) or bone marrow transplantation (BMT) manifested severe bone involvement for the first time during or after treatment. All cases occurred in children in whom ERT doses had been lowered after only brief administration of higher starting doses (n=3) or partial donor marrow engraftment resulted in low glucocerebrosidase (GCR) activity (n=1). These observations suggest that splenectomy may correlate with accelerated skeletal deterioration with severe skeletal disease, at least in patients with severe phenotypic expression. They also suggest that it is important that sufficient GCR is available in paediatric patients with severe phenotypic expression. Hence ERT dosages should be based on disease severity and on age, with sustained administration of full doses in patients at greater risk of important skeletal complications.     

Enzyme therapy in Gaucher disease type 1: dosage efficacy and adverse effects in 33 patients treated for 6 to 24 months

Gaucher disease is the most frequent lysosomal storage disease and the most prevalent genetic disease among the Ashkenazi Jews (q approximately 0.047). The disease results from inherited defects of acid beta-glucosidase and the accumulation of the substrate, glucosylceramide, in cells of monocyte/macrophage origin. The therapeutic response to macrophage-targeted (alpha-mannosyl-terminated) alglucerase (Ceredase, at 60 to 15 IU/kg every 2 weeks) was analyzed in 33 patients (age range, 2 to 63 years; 15 splenectomized) with extensive Gaucher disease over periods of 6 to 24 months. The efficacy of several different doses and dosage reductions was evaluated. In patients with anemia (n = 30) and/or thrombocytopenia (n = 19), hemoglobin levels and platelet counts increased by 0% to 178% and 15% to 155%, respectively, within 3 to 12 months. In patients with splenomegaly (n = 17) and/or hepatomegaly (n = 28), liver and spleen volumes decreased in 6 months from 7% to 64% and 8% to 84% by 12 months, respectively. Hematologic and visceral improvements were noted at any doses between 60 and 15 IU/kg every 2 weeks. Furthermore, these positive initial therapeutic responses were persistent throughout therapy, with doses reduced by 50%. Pulmonary Gaucher disease did not improve clinically in 3 patients. Unrelated cirrhotic (n = 2), cholestatic (n = 1), or renal disease (n = 1) did not influence the rate of patient improvement. Two of five patients who developed serum antibodies against alglucerase during the first 6 to 12 months of therapy had mild antibody reactions. This study shows similar regression of clinical Gaucher disease manifestations with enzyme therapy, using doses between 30 and 60 IU/kg every 2 weeks. Therapeutic efficacy was not diminished after 50% to 75% dose reductions or in the presence of anti-enzyme antibodies.     

Treatment of renal anemia with darbepoetin alfa administered once every other week in predialysis patients with chronic kidney disease and previously treated with epoetin alfa

Darbepoetin alfa is an erythropoiesis-stimulating glycoprotein with up to 3 times longer half-life than recombinant human erythropoietin (rHuEPO) in humans. The aim of this study was to assess the efficacy and safety of darbepoetin alfa given once every other week as treatment of anemia in predialysis patients with chronic renal failure (CRF) previously treated with once-weekly epoetin alfa. A total of 42 CRF patients were included, all of whom had previously been treated with epoetin alfa and showed stable hemoglobin (Hb) levels without dose changes during the last 8 weeks prior to enrolment in this study. All patients received s.c. darbepoetin alfa once every other week at doses calculated from the protein mass equivalence between rHuEPO and darbepoetin alfa. Follow-up lasted for 24 weeks. Dose adjustments were conducted to preserve target Hb levels between 11 and 13 g/dl. Thirty-nine patients completed the 24 weeks of study. Hb levels increased during follow-up [mean values of 0.39 (p < 0.002), 0.58) (p < 0.001), and 0.83 g/dl (p < 0.001) at 8, 16 and 24 weeks, respectively] despite reducing the darbepoetin alfa dose up to 15% at 24 weeks [from 0.192 microg/kg body weight to 0.185, 0.178 and 0.163 at 8, 16, and 24 weeks, respectively (p < 0.001)]. No adverse events related to darbepoetin alfa were reported. In conclusion, these results show s.c. administration of darbepoetin alfa once every other week was superior to weekly epoetin alfa as a maintenance treatment for anemia in predialysis CRF patients, since the former provided higher Hb levels. Moreover, darbepoetin alfa administration was safe in these patients.