Evaluation of a pediatric liquid formulation to improve 6-mercaptopurine therapy in children.

BACKGROUND: 6-mercaptopurine (6-MP), a key drug for treatment of acute lymphoblastic leukemia (ALL), has until recently had no adequate formulation for pediatric patients. Several approaches have been taken but the only oral paraben-free 6-MP liquid formulation named Loulla was developed and evaluated in the target population. Preclinical and clinical evaluations were performed according to a Pediatric Investigation Plan, in order to apply for a Pediatric Use Marketing Authorization. METHODS: The pre-clinical study assessed the maximum tolerated dosage-volume and evaluated local mucosal toxicity of 28 daily administrations in treated compared to controls gold hamsters. The multi-centre clinical study was single-dose, open-label, crossover trial, conducted in 15 ALL children during maintenance therapy. The bioavailability and palatability of a single 50mg fixed dose of Loulla compared to 50mg registered tablets were evaluated in a random order on two consecutive days. Seven blood samples over 9h were obtained each day to determine 6-MP pharmacokinetic parameters, including Tmax, Cmax, AUC0-9 and AUC0-∞. A questionnaire adapted to children testing Loulla palatability and preference for either Loulla or the usual 6-MP tablet was completed. Occurrence of adverse events was determined at study visits by vital sign measurements, patient's spontaneous reporting, investigator's questioning and clinical examination. RESULTS: The preclinical study in gold hamsters showed that dosage-volume of 75 mg/kg/day was well tolerated. The relative bioavailability of liquid Loulla formulation compared to the reference presentation is 76% for AUC0-9 and AUC0-∞ and 80% for Cmax. The taste of Loulla and the mouth feeling after ingestion compare favorably to the tablet. No adverse event occurred. CONCLUSION: Pharmacokinetic, palatability and safety data support the use of Loulla in children.

Autosomal dominant STAT3 deficiency and hyper-IgE syndrome: molecular, cellular, and clinical features from a French national survey.

Autosomal dominant deficiency of signal transducer and activator of transcription 3 (STAT3) is the main genetic etiology of hyper-immunoglobulin (Ig) E syndrome. We documented the molecular, cellular, and clinical features of 60 patients with heterozygous STAT3 mutations from 47 kindreds followed in France. We identified 11 known and 13 new mutations of STAT3. Low levels of interleukin (IL)-6-dependent phosphorylation and nuclear translocation (or accumulation) of STAT3 were observed in Epstein-Barr virus-transformed B lymphocytes (EBV-B cells) from all STAT3-deficient patients tested. The immunologic phenotype was characterized by high serum IgE levels (96% of the patients), memory B-cell lymphopenia (94.5%), and hypereosinophilia (80%). A low proportion of IL-17A-producing circulating T cells was found in 14 of the 15 patients tested. Mucocutaneous infections were the most frequent, typically caused by Staphylococcus aureus (all patients) and Candida albicans (85%). Up to 90% of the patients had pneumonia, mostly caused by Staph. aureus (31%) or Streptococcus pneumoniae (30%). Recurrent pneumonia was associated with secondary bronchiectasis and pneumatocele (67%), as well as secondary aspergillosis (22%). Up to 92% of the patients had dermatitis and connective tissue abnormalities, with facial dysmorphism (95%), retention of decidual teeth (65%), osteopenia (50%), and hyperextensibility (50%). Four patients developed non-Hodgkin lymphoma. The clinical outcome was favorable, with 56 patients, including 43 adults, still alive at the end of study (mean age, 21 yr; range, 1 mo to 46 yr). Only 4 patients died, 3 from severe bacterial infection (aged 1, 15, and 29 yr, respectively). Antibiotic prophylaxis (90% of patients), antifungal prophylaxis (50%), and IgG infusions (53%) improved patient health, as demonstrated by the large decrease in pneumonia recurrence. Overall, the prognosis of STAT3 deficiency may be considered good, provided that multiple prophylactic measures, including IgG infusions, are implemented.

Liposomal daunorubicin (Daunoxome) and polyethylated glycol conjugated asparaginase (PEG-ASPA) in children with relapsed and refractory acute lymphoblastic leukemia treated on compassionate basis.

BACKGROUND: Daunoxome (DNX) is an encapsulated form of daunorubicin in liposomal vesicles with suggested better pharmacokinetics, pharmacodynamics and lesser cardio toxicity than the free form. Polyethyl glycol asparaginase (PEG-ASPA), a modified form of L-asparaginase, has better activity and lesser immunogenicity than its native molecule. AIM: To evaluate on a compassionate basis, the combination of Daunoxome and PEG-ASPA, as regard to efficacy and toxicity, as a salvage treatment in refractory/relapsed childhood ALL. METHODS: The combination of these 2 drugs were used in 9 multiple relapsed or refractory ALL children on the basis of: DNX weekly 100 mg/m2 D1, 8, 15. PEG-ASPA single, 2500IU/m2 dose D15. Vinca alkaloids and corticosteroids were associated. RESULTS: Median hospital stay was 4 days (0-55). COMPLICATIONS: Neutropenia grade IV n=4, grade III infection n=6, grade II cardiac toxicity n=1, grade III allergy, grade III hemostasis disorders, thrombosis, n=1 respectively. All patients achieved complete remission (CR) except one who died from disease progression. 8 patients were subjected to hematopoietic stem cell transplantatation (HSCT). Two patients of them are alive and well, 4 died from transplant related causes and 2 from disease progression. CONCLUSION: Salvage treatment containing DNX and PEG-ASPA, of small sample childhood ALL with very advanced disease, is feasible as regard toxicity and response rate allowing to HSCT and possible cure.