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111.
Statutory reimbursement agencies as well as private insurers throughout member states of the Organization for Economic Cooperation and Development (OECD) reimburse the cost of medicines on the basis of criteria that include robust clinical evidence, budget impact analysis, and incremental cost effectiveness. The Centers for Medicare and Medicaid Services (CMS) in the US are no exception to this rule and are, in principle, seeking to maximize benefit for their Medicare enrollees, whilst ensuring reasonable drug outlays for the small number of drugs that they reimburse. This paper provides a retrospective analysis of the way two functionally equivalent drugs are treated for reimbursement purposes by the CMS; the period under consideration was 2001–3. The two drugs, epoetin-α and darbepoetin-α, are used for the treatment of anemia in renal failure and in patients receiving chemotherapy. By reviewing the publicly available pharmacological and clinical data of epoetin-α and darbepoetin-α, the paper confirms the two drugs’ functional equivalence, despite their structural differences. The implications of dose conversion ratios and costs to Medicare are subsequently explored. It is argued that the issue of dose equivalence between epoetin-α and darbepoetin-α has significant implications for patients, practitioners, and payors. A payor’s perspective is adopted in this respect, whereby clinical evidence and pricing data are used simultaneously. Based on the clinical evidence, a dose conversion ratio for epoetin-α:darbepoetin-α is established, which achieves a comparable clinical effect for the two drugs and this is set to be <254IU:1μg. The incremental costs to Medicare are calculated subsequently. The Average Wholesale Price and the Outpatient Prospective Payment System rule that Medicare uses to reimburse providers are used and suggest that treatment of cancer patients with chemotherapy-related anemia with epoetin-α would save Medicare an estimated $US600 million each year. Patients would also benefit significantly in terms of lower co-payments for epoetin-α. The evidence is supportive of the decision made by the CMS to reimburse the two drugs at the rate reflecting the achievement of comparable clinical effects and therefore reducing the pass-through payments for darbepoetin-α to zero for the 2002–3 fiscal year. 相似文献
112.
Objective: To study the diagnostic value of T2^*-weighted first-pass perfusion imaging in breast tumors. Methods: We analyzed the magnetic resonance imaging (MRI) information along with the pathological and immunohistochemistry results. Magnetic resonance imaging was performed in 28 patients with breast tumor. The time to signal intensity curves were generated according to the T2^*-weighted first-pass perfusion imaging. The curve's maximal signal intensity drop rate and maximal signal intensity decrease time were analyzed and compared with the pathological diagnoses after surgery. Results: Malignant breast lesions showed higher maximal signal intensity drop rate (44.69% ± 17.07 vs. 17.22% ±7.49, P 〈 0.001) than benign lesions, but there was no significant difference of maximal signal decrease time between those two lesions (23.94 s ± 4.92 vs. 20.02 s ± 6.83, P 〉 0.05). Conclusion: The T2^*-weighted first-pass perfusion imaging has enough sensitivity and specificity in breast tumor diagnosis. 相似文献
113.
114.
昆虫色氨酸羟化酶的研究进展 总被引:5,自引:0,他引:5
色氨酸羟化酶(tryptophan hydroxylase、TPH)为5-羟色胺(5-hydroxytryptamine,5-HT)合成的限速酶,具有专一性,在组织中含量较低,且具有不稳定性。TPH的活性是5-HT合成的唯一前提,因此它可以作为5-HT能神经元的特异标志,也可以作为5-HT能神经元的一个分化特征。它的存在,住区分神经细胞特征方面比5-HT本身的含苗更有价值。因而近年来TPH迅速成为国际研究的热点和难点之一。本文主要就TPH在昆虫中的存在形式、调节机制及进化地位等方面已取得的研究进展作一简述。 相似文献
115.
Single or combined monoclonal antibodies (McAbs) Zh53, Zh820, and Zh2-1 have been used to eliminate malignant clonogenic cells from human bone marrow. The test of cytotoxicity showed that all of these McAbs could express high specific cytotoxic action against HL-60 cells and were selectively complement-dependent cytotoxic to various types of fresh leukemic cells. Clonogenic assay detected that single treatment with antibody and rabbit complement (RC) could reduce clonogenic units of HL-60 cells by more than 2 logs and two treatments reduced clonogenic units by more than 4 logs. However, combination of 2 McAbs could reduce clonogenic units by 4-5 logs. The data suggest that multiple treatments with McAbs and RC or a combination of 2 McAbs are more effective than a single treatment in eliminating clonogenic tumor cells. Treatment of normal human bone marrow with Zh53, Zh2-1 and RC did not produce a loss of normal CFU-GM, but treatment with Zh820 reduced the clonic units of normal CFU-GM by 24%.
相似文献
116.
The toxic effects of nitroquine-dapsone compound(NQD)in mice and dogs were studied.The therapeutic index of NQDin mice is 1911,the greatest among the 6 antimalarials tested.Thetoxic effects of NQD(50 mg/kg/day for 3 days per os)and nitro-quine in dogs were manifested by injuries on the adrenal cortexand intestinal epithelium.When folic acid(4 mg/kg/day for 4 days)or calcium leucovorinum(0.3 mg/kg/day for 4 days)were usedconcomitantly with NQD,the death rate and the incidence of dia-rrhea in the toxicated dogs were greatly reduced,the injury on theintestinal epithelium was much milder,and the goblet cells weremuch more numerous than those without treatment.The results suggestthat folic acid and calcium leucovorinum can protect the undifferen-tiated cells in the intestinal crypts from being injured by NQD. 相似文献
117.
118.
Zhang Gu-sheng章谷生 Hu Fang-yuan胡方远 Ye Qing-zhen叶庆祯 Yan Yong-tang严咏棠Immunology Laboratory Shanghai Institute of Biologicat Products Shanghai 《中华医学杂志(英文版)》1986,99(4):343-346
Neurotropin (NSP) is an extract isolated from
the skin of rabbits inoculated with vaccinia virus.
The present study examines the possible action of
NSP on the number and function of immunocompe
tent cells in mice. The experiment showed that NSP
had no effect on both T and B lymphocytes of nor-
malimmunized mouse spleen. The degree of plaque
forming cell reaction and titre of specific antibody
showed no significant differences when the NSP
treated group and controls were compared. How-
ever, NSP exhibited promotive effect on specific
antigen binding cells in the early stage of immune
responses. It was also noted that the rosette forming
capacity of human T lymphocytes in vitro was restor-
ed markedly by NSP. These results suggest that
NSP possesses certain immunostimulating activity,
particularly on the specific antigen binding cells and
human T lymphocytes. 相似文献
119.
PURPOSE: To evaluate a computational approach that incorporates experimental data in preclinical models to depict doxorubicin human tissue pharmacokinetics. EXPERIMENTAL DESIGN: Beagle dogs were given 2 mg/kg doxorubicin as i.v. bolus, 4-h infusion, or 96-h infusion. Concentrations in plasma, prostate (target tissue), heart (toxicity), and major tissues for disposition were determined and modeled. Model parameters were obtained after the bolus injection with model validation based on the 4-h and 96-h infusion data. Clinical pharmacokinetic data and scale-up gave doxorubicin profiles in human prostate and heart. RESULTS: In agreement with in vitro results, tissues were best modeled with two compartments, one rapidly and one slowly equilibrating. The developed tissue distribution model predicted concentrations for all three administration regimens well, with an average deviation of 34% (median, 29%). Interspecies scale-up to humans showed that the change from a bolus injection to a slow, 96-h infusion (a) had different effects on the drug partition and accumulation in heart and prostate, and (b) lowered the peak concentration in the plasma by approximately 100-fold but had relatively little effect on maximal heart concentration ( approximately 33% lower). The simulated drug exposure in a human prostate was above the exposure required to inhibit tumor proliferation but was 30 to 50 times below that needed for cell death. CONCLUSION: The present study shows a computation-based paradigm for translating in vitro and in vivo preclinical data and to estimate and compare the drug delivery and pharmacokinetics in target tissues after different treatment schedules. 相似文献
120.