PEGylated Recombinant Adenosine Deaminase Maintains Detoxification and Lymphocyte Counts in Patients with ADA-SCID.

PURPOSE: Metabolic detoxification with enzyme replacement therapy (ERT) promotes immune recovery in patients with adenosine deaminase (ADA)-deficient severe combined immunodeficiency (ADA-SCID). Elapegademase is a PEGylated recombinant bovine ADA ERT developed to replace the now-discontinued bovine-derived pegademase. This study was a 1-way crossover from pegademase to elapegademase in 7 patients with ADA-SCID to assess efficacy and safety outcomes for elapegademase. METHODS: After once-weekly pegademase dosage was adjusted to achieve therapeutic metabolic detoxification and trough ADA activity, patients transitioned to a bioequivalent dose of elapegademase. Maintenance of metabolic detoxification and adequate ADA activity were evaluated periodically. RESULTS: One patient withdrew after 2 doses of an early elapegademase formulation due to injection-site pain caused by EDTA. The 6 remaining patients completed 71-216 weeks of elapegademase therapy with a formulation that did not contain EDTA. In these patients, elapegademase improved ADA activity compared with pegademase and maintained metabolic detoxification. Total lymphocyte counts increased for all completer patients from between 1.2- and 2.1-fold at the end of study compared with baseline. Elapegademase had a comparable safety profile to pegademase; no patient developed a severe infectious complication. Three patients had transient, non-neutralizing antibodies to pegademase, elapegademase, and/or polyethylene glycol ≤ 47 weeks of treatment without effect on trough plasma ADA activity or trough erythrocyte deoxyadenosine nucleotide levels. CONCLUSION: Elapegademase was safe, well tolerated, achieved stable trough plasma ADA activity with weekly dosing, was effective in maintaining metabolic detoxification, and was associated with maintenance or improvements in lymphocyte counts compared with pegademase therapy in patients with ADA-SCID.

Effect of Caspofungin vs Fluconazole Prophylaxis on Invasive Fungal Disease Among Children and Young Adults With Acute Myeloid Leukemia: A Randomized Clinical Trial.

Importance: Children, adolescents, and young adults with acute myeloid leukemia are at high risk of life-threatening invasive fungal disease with both yeasts and molds. Objective: To compare the efficacy of caspofungin vs fluconazole prophylaxis against proven or probable invasive fungal disease and invasive aspergillosis during neutropenia following acute myeloid leukemia chemotherapy. Design, Setting, and Participants: This multicenter, randomized, open-label, clinical trial enrolled patients aged 3 months to 30 years with newly diagnosed de novo, relapsed, or secondary acute myeloid leukemia being treated at 115 US and Canadian institutions (April 2011-November 2016; last follow-up June 30, 2018). Interventions: Participants were randomly assigned during the first chemotherapy cycle to prophylaxis with caspofungin (n = 257) or fluconazole (n = 260). Prophylaxis was administered during the neutropenic period following each chemotherapy cycle. Main Outcomes and Measures: The primary outcome was proven or probable invasive fungal disease as adjudicated by blinded central review. Secondary outcomes were invasive aspergillosis, empirical antifungal therapy, and overall survival. Results: The second interim efficacy analysis and an unplanned futility analysis based on 394 patients appeared to have suggested futility, so the study was closed to accrual. Among the 517 participants who were randomized (median age, 9 years [range, 0-26 years]; 44% female), 508 (98%) completed the trial. The 23 proven or probable invasive fungal disease events (6 caspofungin vs 17 fluconazole) included 14 molds, 7 yeasts, and 2 fungi not further categorized. The 5-month cumulative incidence of proven or probable invasive fungal disease was 3.1% (95% CI, 1.3%-7.0%) in the caspofungin group vs 7.2% (95% CI, 4.4%-11.8%) in the fluconazole group (overall P = .03 by log-rank test) and for cumulative incidence of proven or probable invasive aspergillosis was 0.5% (95% CI, 0.1%-3.5%) with caspofungin vs 3.1% (95% CI, 1.4%-6.9%) with fluconazole (overall P = .046 by log-rank test). No statistically significant differences in empirical antifungal therapy (71.9% caspofungin vs 69.5% fluconazole, overall P = .78 by log-rank test) or 2-year overall survival (68.8% caspofungin vs 70.8% fluconazole, overall P = .66 by log-rank test) were observed. The most common toxicities were hypokalemia (22 caspofungin vs 13 fluconazole), respiratory failure (6 caspofungin vs 9 fluconazole), and elevated alanine transaminase (4 caspofungin vs 8 fluconazole). Conclusions and Relevance: Among children, adolescents, and young adults with acute myeloid leukemia, prophylaxis with caspofungin compared with fluconazole resulted in significantly lower incidence of invasive fungal disease. The findings suggest that caspofungin may be considered for prophylaxis against invasive fungal disease, although study interpretation is limited by early termination due to an unplanned interim analysis that appeared to have suggested futility. Trial Registration: ClinicalTrials.gov Identifier: NCT01307579.

Pediatric dosing of rituximab revisited: serum concentrations in opsoclonus-myoclonus syndrome.

To longitudinally assess serum concentrations of rituximab, it was administered intravenously to 25 children with opsoclonus-myoclonus syndrome at 375 mg/m2 on each of 4 consecutive weeks with (Group I and II) or without (Group III) conventional immunotherapy. Serum rituximab levels, drawn before and after each infusion and at later intervals, were analyzed by enzyme-linked immunosorbent assay. Rituximab concentration increased stepwise with each infusion, dropping by the next infusion, thereby forming 4 discrete peaks (Cmax) and troughs (Cmin). It then fell precipitously to trace levels at 4 months. However, Cmax and Cmin curves differed significantly between groups. Compared with the youngest children (Group I), the oldest (Group III) had a 34% lower rituximab concentration at the fourth infusion, 45% less IgM depletion 1 month later, and received 20% less rituximab when the dose was recalculated as mg/kg. Serum IgM and rituximab levels were negatively correlated. Peak rituximab concentration did not correlate with adrenocorticotropic hormone dose. These results indicate that the degree of serum IgM depletion is a useful indicator for rituximab dose equivalency in children of different ages. They also suggest that pediatric rituximab dosing should be based on body weight, not surface area. (ClinicalTrials.gov NCT00244361).

Proteinuria in children with sickle cell disease.

BACKGROUND: Sickle cell nephropathy is characterized by proteinuria that starts in childhood and may lead to renal failure. Microalbuminuria is used as a marker of glomerular damage. There are no data on the extent and type of proteinuria other than microalbuminuria in children with sickle cell disease (SCD). Our goal was characterization of glomerular permselectivity and tubular proteinuria in children with SCD. The improved characterization will allow earlier recognition and prevention of renal damage. METHODS: Thirty-two stable patients with haemoglobin SS (HbSS) (15 boys and 17 girls, age 9.57 +/- 5.45 years, 8 months to 19 years) were investigated. All patients had normal renal function and tested negative for proteinuria with a dipstick method. Markers of glomerular permselectivity used were albumin (marker of charge selectivity and less severe pore-size selectivity) and immunoglobulin G (IgG, marker of more severe pore-size selectivity). The marker of tubular injury used was retinol-binding protein (RBP, marker of proximal tubular dysfunction). These proteins were measured in urine spot samples using nephelometry. We did not include a control group as values in healthy subjects were previously published. RESULTS: Total protein excretion was elevated in 41% (13/32) of all patients and, of these 13 patients, 38.5% (5/13) had increased microalbuminuria, 15% (2/13) had increased excretion of RBP and 23% (3/13) had increased excretion of IgG. Increased total proteinuria that was not detected by testing for microalbuminuria was found in 61.5% (8/13) of patients. The youngest patient was 3 years old. Increased microalbuminuria was present in 25% (8/32) of all patients and was detected as early as 4 years of age. Of these, 62% (5/8) also had increased total protein excretion and 62% (5/8) also had increased IgG excretion. A total of 62.5% were older than 10 years. RBP excretion was elevated in 16% (5/32) of patients, all of whom were 7-14 years old. None of these patients had increased microalbuminuria or increased excretion of IgG. IgG excretion was elevated in 16% (5/32) of patients and was accompanied by increased microalbuminuria. All patients with increased IgG excretion were > or = 13 years old. We found a weak positive correlation between microalbuminuria and age (0.323, P = 0.07). We did not find a significant correlation between any type of proteinuria and disease morbidity. Ten of the thirty-two patients received hydroxyurea treatment and 60% (6/10) had no proteinuria. Twelve of the thirty-two patients received chronic exchange transfusions and 42% (5/12) had no proteinuria. CONCLUSION: We found early glomerular selectivity damage in children with SCD, which is secondary to both size-selectivity and charge-selectivity impairment. Microalbuminuria alone does not adequately detect early renal damage in children with SCD. Proximal tubular dysfunction is seen in younger children and is independent of glomerular damage. We suggest that children with SCD be tested for both total protein and IgG excretion in the urine in addition to albumin. Knowing the extent and type of renal damage may allow earlier recognition of renal injury and prompt earlier initiation of preventive therapies.

Chronic immune thrombocytopenic purpura in children: assessment of rituximab treatment.

OBJECTIVES: This study examined the efficacy and safety of rituximab in children with chronic immune thrombocytopenic purpura. STUDY DESIGN: Twenty-four patients, 2 to 19 years of age, with platelet counts <30,000/mcL (microliter 2), received 375 mg/m 2 rituximab in 4 weekly doses. Platelet response was characterized as complete (CR) if a count >150,000/mcL was achieved; partial (PR) if 50,000 to 150,000/mcL; minimal (MR) if the count increased by >20,000/mcL to a peak count >30,000/mcL but <50,000/mcL; or no response (NR). RESULTS: Fifteen of 24 patients (63%) achieved a CR lasting 4 to 30 months, 9 of which are ongoing. Two had PRs lasting 4 and 6 months; 2 had MRs lasting 5 and 8 months, and 5 did not respond. Pruritus, urticaria, and throat tightness (but no respiratory distress) occurred with the first infusion in a small number of children. Three patients had serum sickness after the first, second, and third infusions, respectively. No increased frequency or severity of infections was seen, although immunoglobulin levels decreased to below the normal range in 6 of 14 cases. CONCLUSIONS: Rituximab may be a useful treatment for chronic immune thrombocytopenic purpura in children with a >50% CR rate lasting an average of 13 months, with 9 of 15 CRs ongoing (8 lasted 6 months or longer). There was no substantial toxicity other than transient serum sickness.

Efficacy and safety of amphotericin B lipid complex in 548 children and adolescents with invasive fungal infections.

BACKGROUND: The safety and efficacy of amphotericin B lipid complex injection (ABELCET; Enzon Pharmaceuticals, Piscataway, NJ) was assessed in 548 children and adolescents 0-20 years of age who were enrolled in the Collaborative Exchange of Antifungal Research (CLEAR) registry. To our knowledge, this is the largest series of pediatric patients treated for invasive mycoses with a single agent. All patients had cancer or had received a bone marrow, cord blood or solid organ transplant and were treated with amphotericin B lipid complex for documented or suspected fungal infection. METHODS: The CLEAR database was queried for all patients 0-20 years of age from 1996 to 2000. Data gathered included demographic variables, underlying disease type, reasons for the use of amphotericin B lipid complex injection, dosing information, clinical response and renal effects. RESULTS: Most patients were either intolerant of or refractory to conventional antifungal therapy, and almost one-half were neutropenic at treatment onset. Of the 548 patients, 300 (54.7%) were transplant recipients and 393 (71.7%) had received one or more concomitant nephrotoxins. Candida and Aspergillus were the most commonly isolated species in patients with proven or probable infections. Response data were evaluable for 255 of the 285 patients with documented single or multiple pathogens. A complete (cured) or partial (improved) response was achieved in 54.9% of patients, with an additional 16.9% of patients having a stable outcome. Among patients with proven Aspergillus infection, the response rates (cured + improved) were 40.5 and 37.5% in transplant and nontransplant patients, respectively. When stable responses were added, the response rates were 48.6 and 71.9%, respectively. There were few clinically significant deleterious effects on renal function. There was no significant difference between the rates of new hemodialysis versus baseline hemodialysis. Elevations in serum creatinine of >1.5 x baseline and >2.5 x baseline values were seen in 24.8 and 8.8% of all patients, respectively. CONCLUSIONS: The safety and efficacy data from this large pediatric population support the use of amphotericin B lipid complex injection for treatment of invasive fungal infections in immunocompromised children and adolescents, including the high risk subgroup of transplant recipients. The overall response rate and safety profile in pediatric patients who were largely intolerant of or refractory to conventional antifungal therapy were consistent with earlier reported findings of smaller trials.

Autologous transplantation for diffuse aggressive non-Hodgkin lymphoma in first relapse or second remission.

We evaluated the results of high-dose chemotherapy and autologous hematopoietic stem cell transplantation in patients with diffuse aggressive non-Hodgkin lymphoma (NHL) in first relapse (Rel 1) or second complete remission (CR 2). Data were evaluated from the Autologous Blood and Marrow Transplant Registry on 429 patients with diffuse aggressive NHL who underwent transplantation in Rel 1 or CR 2. Transplantations were performed between 1989 and 1996 and were reported to the Autologous Blood and Marrow Transplant Registry by 93 centers in North and South America. The probability of 3-year survival was 44% (95% confidence interval [CI], 33%-55%). The probability at 3 years of progression-free survival was 31% (95% CI, 27%-36%). Patients who underwent transplantation in CR 2 had a 3-year probability of progression-free survival of 38% (95% CI, 30%-46%) compared with 28% (95% CI, 22%-33%) for those who were not in remission at the time of transplantation (P <.001). In multivariate analysis, chemotherapy resistance, increased lactic dehydrogenase at diagnosis, an interval of <12 months from diagnosis to relapse, age >or=40 years, and use of myeloid growth factors to accelerate posttransplantation bone marrow recovery were adverse predictors of survival. High-dose chemotherapy and autologous hematopoietic stem cell transplantation for patients with diffuse aggressive NHL in CR 2 or Rel 1 resulted in better outcome for patients with chemotherapy-sensitive disease, longer relapse-free intervals, and age <40 years. Exposure to myeloid growth factors to accelerate recovery for recipients of bone marrow grafts may increase the risk of disease progression or death.

An expanded phase I/II trial of cyclophosphamide, etoposide, and carboplatin plus total body irradiation with autologous marrow or stem cell support for patients with hematologic malignancies.

The major cause for failure of autologous stem cell transplantation for hematologic malignancies is the risk of recurrent disease. As a result, new treatment regimens that include novel agents or combinations of agents and approaches are needed. The current report describes a large Phase I/II, single-center trial that includes 60 patients with a variety of hematologic malignancies. These patients received a fixed dose of carboplatin (1 g/m(2)/d x 72 hours by CI) etoposide (600 mg/m(2)/d x 3 days) and cyclophosphamide (2 g/m(2)/d x 3 days), plus escalating doses of total body irradiation (TBI) (at 1000, 1200, and 1295 cGy) over 3 days. Eleven patients received infusion of autologous marrow, 32 received peripheral blood stem cells, and 17 patients received both. The maximum tolerated dose of this regimen was a radiation dose of 1200 cGy given in 200-cGy fractions BID x 3 days. The dose-limiting toxicity was mucositis, with 97% of patients requiring narcotic analgesia for mouth pain. Overall treatment-related mortality was 6.7%, with 2 of the 4 deaths occurring in a group of 9 patients aged 60 and older. Responses were seen in all patient groups, but the most encouraging outcomes were seen in 12 patients with high-risk or advanced acute myelocytic lymphoma (AML), 7 of whom remain alive and free of disease beyond 5 years. This regimen is intensive and causes considerable mucositis but is otherwise well tolerated and has demonstrated activity in a number of hematologic malignancies, especially AML.