Fabry disease, an inherited deficiency of the lysosomal enzyme ␣-galactosidase A, causes progressive intralysosomal accumulation of globotriaosylceramide (GL-3) and premature death from renal, cardiac, and cerebrovascular manifestations. To determine the long-term safety and efficacy of recombinant human ␣-galactosidase A, an open-label, phase III extension study was conducted, involving 58 patients who had classic Fabry disease and completed a 20-wk, double-blind, randomized, placebo-controlled, phase III study of agalsidase ␤ and were transitioned to an extension trial to receive biweekly 1 mg/kg agalsidase ␤ for up to an additional 54 mo. GL-3 accumulation was evaluated in the capillary endothelia of the skin, kidney, and heart. Renal function was assessed. By month 54, all patients with optional kidney biopsies (n ‫؍‬ 8) maintained complete GL-3 clearance in renal capillary endothelial cells and multiple cell types. Continued, complete clearance of skin (31 of 36) and heart (six of eight) capillary endothelium was demonstrated. Mean plasma GL-3 levels remained decreased in the normal range. Median serum creatinine and estimated GFR remained stable (normal) in patients with renal data at month 54 (n ‫؍‬ 41). Six patients had renal disease progression; most (four of six) were older than 40 yr and had significant proteinuria at baseline and evidence of sclerotic glomeruli pretreatment. Adverse events were generally mild and unrelated to treatment. The most common treatment-related adverse events were infusion-associated reactions, which decreased over time. Long-term agalsidase ␤ therapy stabilizes renal function in patients without renal involvement at baseline, maintains reduction of plasma GL-3, and sustains GL-3 clearance in capillary endothelial cells and multiple renal cell types.

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BACKGROUND Children who are treated for myeloid leukemia associated with Down syndrome (DS) experience superior survival compared with children who have myeloid leukemia without DS. To maintain excellent outcomes while avoiding toxicity, the Children’s Oncology Group (COG) conducted the phase 3 trial COG A2971, the first trial solely designed to provide uniform treatment of myeloid leukemia in North American children with DS. A2971 eliminated 2 induction drugs and 3 months of maintenance therapy from the standard-timing regimen of dexamethasone, cytarabine, 6-thioguanine, etoposide, and rubidomycin/daunomycin (DCTER) used in the previous study (Children’s Cancer Group [CCG] 2891). METHODS COG A2971 was a multi-institutional, nonrandomized, clinical trial that enrolled 132 patients who had DS with either acute myeloid leukemia (n = 91) or myelodysplastic syndrome (n = 41). RESULTS The median follow-up was 4.8 years (range, 0.8–8.6 years), the median age at diagnosis was 1.7 years (range, 0.3–13.6 years), and the median white blood cell count was 6200/μL (range, 900–164,900/μL). The remission rate (92.7% ± 6%) was similar to that reported in the CCG 2891 study (91.3% ± 5%; P = .679). The 5-year event free survival (EFS) rate was 79% ± 7% (vs 77% ± 7% in CCG 2891; P = .589), the disease-free survival (DFS) rate was 89% ± 6% (vs 85% ± 6% in CCG 2891; P = .337), and the overall survival rate was 84% ± 6% (vs 79% ± 7% in CCG 2891; P = .302). Induction day-14 bone marrow response trended toward a more favorable outcome (EFS: P = .12). Age >4 years was an adverse risk factor (5-year EFS rate: 33% ± 38% for children aged >4 years [median, 8.5 years; n = 6] vs 81% ± 7% for children ages 0–4 years [median, 1.7 years; n = 126]; P = .001). CONCLUSIONS The COG A2971 trial reduced the chemotherapy dose and maintained survival to that achieved by the CCG 2891 trial in children who had myeloid leukemia associated with DS.

Background: Diamond-Blackfan anemia (DBA) is an inherited bone marrow failure syndrome characterized by anemia, short stature, congenital anomalies, and cancer predisposition. Most cases are due to mutations in genes encoding ribosomal proteins (RP) leading to RP haploinsufficiency. Effective treatments for the anemia of DBA include chronic red cell transfusions, long-term corticosteroid therapy, or hematopoietic stem cell transplantation. In a small patient series and in animal models, there have been hematologic responses to L-leucine with amelioration of anemia. The study