Oseltamivir for influenza postexposure prophylaxis: economic evaluation for children aged 1-12 years in the U.S.

BACKGROUND: Postexposure prophylaxis (PEP) with oseltamivir (Tamiflu) has been shown to be effective and is approved in children exposed to a case of influenza in a household setting. Given limited healthcare budgets, it is important to understand the costs and cost effectiveness of PEP in children. PURPOSE: This study aims to estimate the cost effectiveness of oseltamivir PEP for children aged 1-12 years in the U.S. METHODS: A decision-tree model with a 1-year time horizon was used to assess the cost effectiveness of oseltamivir PEP for 10 days at approved doses compared with no prophylaxis for children aged 1-12 years who were exposed to a household index case of influenza from the U.S. societal and payer perspectives. Model inputs included U.S. influenza epidemiology data, efficacy data from oseltamivir PEP clinical trials, direct medical resource use and costs for PEP and influenza treatment derived from large U.S. databases, and indirect costs based on caregiver lost productivity. Base-case estimates were tested in extensive sensitivity analyses. RESULTS: For the societal perspective, the model estimated 12,184 fewer cases of influenza per 100,000 children exposed and an incremental cost-effectiveness ratio of $41,452 per quality-adjusted life-year (QALY) gained. Results were most sensitive to the influenza attack rate, PEP protective efficacy, and prescribing patterns for initiating PEP. Probabilistic sensitivity analyses showed that oseltamivir PEP was likely to be cost effective for all willingness-to-pay threshold values above $34,300 per QALY gained. Results were similar for the payer perspective. CONCLUSIONS: Although there is no official cost-effectiveness threshold in the U.S., results from the current study show that when compared with no prophylaxis, oseltamivir PEP for children has cost-effectiveness ratios similar to those of vaccines for preventing influenza.

Cost-effectiveness of treating influenzalike illness with oseltamivir in the United States.

PURPOSE: The cost-effectiveness of treating influenzalike illness (ILI) with oseltamivir in the United States was assessed. METHODS: A decision-analysis model was developed with a one-year time horizon to assess the cost-effectiveness of oseltamivir compared with usual care from societal and payer perspectives for four patient populations: high-risk adults, healthy adults, elderly adults, and children. The model used efficacy data from oseltamivir clinical trials and other published literature and assumed oseltamivir was effective only in individuals infected with influenza virus not resistant to oseltamivir and treated within 48 hours of symptom onset. Direct medical costs were based on resources used; indirect costs were estimated based on time lost from work due to illness and premature mortality. Base-case estimates were tested in one-way sensitivity and variability analyses. RESULTS: From a societal perspective, oseltamivir was cost-effective across all populations modeled, with an incremental cost per quality-adjusted life-year gained of $5,388, $6,317, $7,652, and $16,176 for high-risk adults, children, elderly adults, and healthy adults, respectively. Results were similar from a payer perspective. When indirect costs were included (for all populations except elderly adults), oseltamivir was cost saving. In sensitivity analyses, oseltamivir remained cost-effective across all patient populations for all values tested, except the probability of developing influenza-related pneumonia. Variability analyses showed that oseltamivir remained cost-effective under most scenarios tested. CONCLUSION: Base-case results and sensitivity analyses from a decision-analysis model found that treatment of ILI with oseltamivir was cost-effective compared with usual care from U.S. payer and societal perspectives in all patient populations studied when only direct costs were considered.

Preparation and stability of extemporaneous oral liquid formulations of oseltamivir using commercially available capsules.

OBJECTIVES: To develop a simple, standardized method for the extemporaneous compounding of an oral liquid form of oseltamivir from commercially available Tamiflu 75 mg capsules (Roche Pharmaceuticals) and to determine the stability of oseltamivir in this preparation. DESIGN: Chemical and microbial stability study. SETTING: Laboratory. PARTICIPANTS: None. INTERVENTION: Extemporaneous oral liquid formulations of oseltamivir (15 mg/mL) were prepared in Cherry Syrup (Humco) and Ora-Sweet SF (Paddock Laboratories) using methods consistent with current compounding practice in a pharmacy setting. Preparations were stored in amber glass and amber polyethyleneterephthalate bottles at 5 degrees C +/- 2 degrees C (41 degrees F +/- 4 degrees F) and 25 degrees C +/- 2 degrees C (77 degrees F +/- 4 degrees F) at 60% +/- 5% relative humidity (RH) for 35 days and 30 degrees C +/- 2 degrees C (86 degrees F +/- 4 degrees F) at 65% +/- 5% RH for 13 days. OUTCOME MEASURES: Samples were monitored for appearance, pH, assay, degradation products, and microbiologic stability. RESULTS: The Cherry Syrup preparation, in either bottle type, was stable for up to 35 days under refrigeration (5 degrees C) and up to 5 days at room temperature (25 degrees C). It was not stable when stored at 30 degrees C for 5 days. The Ora-Sweet SF preparation was stable for up to 35 days at 5 degrees C or 25 degrees C and for up to 13 days at 30 degrees C in either bottle type. Both preparations maintained microbiologic stability for 35 days. CONCLUSION: Both preparations are stable under the described conditions and may provide an option in situations where the marketed suspension is unavailable.

[A comparison of radiological outcomes in the surgical treatment of thoraco-lumbar scoliosis by anterior "bone on bone" and posterior spondylodesis]. / Porownanie wynikow radiologicznych operacyjnego leczenia skrzywien piersiowoledzwiowych w skoliozach idiopatycznych metoda spondylodezy tylnej i przedniej "kosc na kosc"

Background. The goal of surgical treatment in idiopathic scoliosis is to assure maximal correction of the curvature with a minimal number of spine segments fused. There are two main methods of spondylodesis: anterior and posterior. Material and methods. We compared radiological outcomes after surgical treatment of idiopathic thoraco-lumbar scoliosis by the anterior method called "bone on bone" and the posterior method using derotating fusion. Group I consisted of patients operated by the posterior technique, while Group II consisted of patients operated by the anterior "bone on bone" technique. Results. In Group I, the mean range of fusion was 7 vertebrae. After surgery the mean curve was 23 degrees (61% correction), while at 1-year follow-up the mean angle was 26 degrees . In Group II, the mean range of fusion was 4 vertebrae. After surgery the mean angle was 15 degrees (78% correction), while at one-year follow-up the mean angle was 16 degrees . Conclusions. The "bone on bone" method of anterior fusion gave greater correction and a shorter range of fusion compared to the posterior approach. At one-year follow-up no major loss of correction was noticed in either group.

[Endoscopic procedures in spinal surgery]. / Zabiegi endoskopowe w chirurgii kregoslupa.

Background. The anterior approach to the spine enables good correction and stabilization of the anterior spinal column. The broad application of the anterior procedure via thoracotomy caused problems, however, due to the gravity of the surgical procedure. The introduction of transthoracic endoscopy has made it possible to avoid the disadvantages of open surgery. Material and methods. Between 2000 and 2003, 129 endoscopic operations were performed in our hospital on 125 patients, suffering from idiopathic scoliosis (77 patients), congenital scoliosis (8), scoliosis in systemic diseases (6), neuromuscular scoliosis (3), cardiogenic scoliosis (1), Scheuermann's kyphosis (8), pathological spine fracture (6), spondylodiscitis (4), chylothorax (2), pectus excavatum - MIRPE technique (10). The mean age at surgery was 15 years, range 4-62. The mean follow-up was 17 months, range 5-36. Results. In the whole group, the mean duration of endoscopy was 112 minutes, and mean intraoperative blood lose was 126 ml. Stable fusion was obtained in all patients. The duration of endoscopic procedures was shorter than the open technique, and intraoperative blood loss was lower. A decreased need for analgesics was also noted after surgery. Conclusions. The advantages of the endoscopic spinal procedure are its minimally invasive nature, good visualization of the operative area, decreased blood loss, and decreased need for analgesics.

Early outcome in the surgical treatment of idiopathic scoliosis by "bone on bone" anterior interbody fusion.

Background. The aim of our study was to evaluate a new surgical method developed by Robert Gaines for the treatment of idiopathic scoliosis, called the "bone on bone" procedure. Material and methods. We examined 100 patients (81 female and 19 male) selected from 259 scoliotic patients operated at our center between 2002 and 2004. The mean age at surgery was 16 years and 2 months (range: 12 yrs, 2 months to 39 yrs). The mean follow-up was 18 months (range: 15-24). The average range of fusion was 5 vertebrae (range 3-6). The mean Cobb angle was 63 degrees (range: 49 degrees -98 degrees ). The mean Cobb angle of upper secondary curve was 32 degrees (range: 9 degrees -70 degrees ), the lower 32 degrees (range: 7 degrees -740). The mean apical vertebral rotation (AVR) was 30 degrees (range: 15 degrees -55 degrees ), apical vertebral translation (AVT) 58 mm (range: 8-110). The average thoracic kyphosis was 19 degrees (range: 8 degrees -40 degrees ), and lumbar lordosis 23 degrees (range: 18 degrees -38 degrees ). Technical note. The anterior transthoracic and /or retroperitoneal approach was performed; all discs on the apex of curvature were removed and no bone grafts were used (fusion by contact of vertebrae surfaces). Transvertebral screws were implanted with stabilization by means of a rod. Results. After surgical treatment the mean Cobb angle was 27 degrees (range 0 degrees -58 degrees ), and the correction of the base angle was 58%. The mean Cobb angle of the upper secondary curve was 25 degrees (range: 4 degrees -60 degrees ), the lower 19 degrees (range: 1 degrees -56 degrees ). The average AVR was 20 degrees (range: 5 degrees -45 degrees ), correction was 33%. The mean AVT was 16 mm (range: 0-62 mm), accounting for a 72% correction of basic translation. The average kyphosis after surgical treatment was 26 degrees (range: 15 degrees -45 degrees ), lordosis 20 degrees (range: 7 degrees -35 degrees ). After a mean 18 months follow-up, the average Cobb angle was 31 degrees (range: 0 degrees -73 degrees ), with average 12% loss of correction. The mean upper secondary curve was 25 degrees (range: 5 degrees -62 degrees ), the lower 21 degrees (range: 2 degrees -55 degrees ). The average thoracic kyphosis was 28 degrees (range: 14 degrees -48 degrees ), lordosis 21 degrees (range: 7 degrees -37 degrees ). The mean AVR and AVT remained at the same level after follow-up. Conclusions. The "bone on bone" procedure allows the surgeon to decrease the number of segments involved in spinal fusion, and gives high correction of idiopathic scoliosis with a low rate of operative complications.

The natural history of idiopathic scoliosis.

Background. The natural history of idiopathic scoliosis is a crucial issue in the planning and assessment of different treatment methods. This article presents the evaluation of scoliotic deformity in immature patients who have been in observation without any treatment. Material and methods. 159 patients (128 girls, 31 boys) were examined between 1971 and 2002. Skoliosis was diagnosed at a mean age of 6 years 4 months (range 2.1-8.10), and observation was concluded at a mean age of 16 years 11 months (range 14.6-20.3). The mean follow-up was 10 years 5 months. The prognostic factors analyzed were: age, sex, Cobb angle, Mehta angle, apical vertebral rotation, specific rotation, Risser test. The progression and regression of curvature was analyzed in different biological age periods, and was measured by calculating the difference in the Cobb angle on successive x-rays divided by the interval between x-rays. Results. The mean progression of curvature before age 5 was 5.7 degrees per year; in the 6-10 age bracket, 2.3 degrees per year; in the 11-15 age bracket, 7.4 degrees per year; in the >15 age bracket, 0.3 degrees per year. The mean progression for patients with Risser 1 was 8.8 degrees per year; Risser 2, 7.3 degrees per year; Risser 3, 5.1 per year; Risser 4, 2.1 degrees per year; Risser 5, 0.3 degrees per year. Conclusions. The progression of curvature in idiopathic scoliosis is variable, and is influenced by age. Knowledge of the natural history of idiopathic scoliosis is a crucial tool in predicting the development of spinal curvature. The Risser test and biological age are the only effective predictors of progression.

Surgical treatment of congenital vertebral displacement Type A in the sagittal plane only: a retrospective study involving eleven cases.

STUDY DESIGN: The essence of congenital vertebral displacement Type A pathology is a congenital structure defect including a vertebral or intervertebral disc with instant curvature of the spinal canal in the sagittal plane. Clinically this defect assumes the shape of kyphosis or kyphoscoliosis. A retrospective review of 11 patients with this congenital deformity was conducted. OBJECTIVES: To evaluate the effectiveness of surgical treatment for congenital vertebral displacement, and to establish the optimal operative management. METHODS: Nine patients with a mean age of 3.3 years (range, 1.8-5.5 years) underwent surgery. Two patients were treated conservatively. All the patients underwent radiologic investigation, which included radiographs, three-dimensional computed tomography scans, and magnetic resonance imaging scans. The neurologic condition was assessed by clinical neurologic examination and somatosensory-evoked potentials. The following surgical techniques were performed: 13 posterior fusions in situ in eight patients; 4 anterior fusions in situ in four patients, 8 total or partial vertebrectomies with anterior fusion and stabilization using cylindric cage in 6 patients, 3 total or partial vertebrectomies with anterior fusion and stabilization using fibula graft in 3 patients, and 5 posterior fusions with instrumentation in 2 patients. The total mean follow-up period was 5.7 years (range, 2.1-9.9 years). RESULTS: The mean follow-up period after the last operation was 22 months (range, 2-48 months). The general results observed during the follow-up period were as follows. Deformity stabilization was obtained in six patients, whereas it was still progressive in three patients. In five patients, regression of neurologic deficits was obtained, whereas in patients, it was stable. Progression of neurologic deficits was observed in one patient (paraplegia). Retrospectively, the best clinical results were achieved after extensive decompression of the spinal cord with anterior stabilization of the spine using a cylindric cage or fibula autograft. These procedures were preceded or followed by posterior fusion. CONCLUSIONS: The findings showed that only extensive vertebrectomy and anterior stabilization using a cylindric cage or fibula graft combined in one operative procedure, preceded or followed by posterior fusion, ensures patients against progression of neurologic deficits and deformity of spine.