Lipitor scientific update |
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Pharmazie. 2006 Sep;61(9):805-6.
Mendoza L, Hajduch M, Plausinaitis R, Platilova V, Emritte N, Svoboda M.
IQA, as, Prague, Czech Republic.
Pharmacokinetic and bioequivalence testing of atorvastatin formulations in healthy male volunteers.
The aim of this study was to compare the bioavailability of two atorvastatin formulations (Divator Drogsan Pharmaceuticals, Ankara, Turkey, as the test formulation, and Lipitor, Pfizer Ireland Pharmaceuticals, Dublin, Ireland, as the reference formulation) in 52 healthy volunteers. The study was conducted using a randomised, single-dose, two-way crossover study with a 2-week washout period between the doses. Since the 90% confidence intervals for Cmax, AUC0-72 and AUC0-proprtional to ratios for both, the parent atorvastatin and its main active metabolite ortho-hydroxy atorvastatin, were within the pre-defined Bioequivalance acceptance limits approved by EMEA, we concluded that the atorvastatin formulation elaborated by Drogsan Pharmaceuticals, was bioequivalent to the Lipitor in its rate and extent of absorption.
J Am Coll Cardiol. 2005 Mar 1;45(5):733-42.
Yonemura A, Momiyama Y, Fayad ZA, Ayaori M, Ohmori R, Higashi K, Kihara T, Sawada S, Iwamoto N, Ogura M, Taniguchi H, Kusuhara M, Nagata M, Nakamura H, Tamai S, Ohsuzu F.
National Defense Medical College, Saitama, Japan.
Effect of lipid-lowering therapy with atorvastatin on atherosclerotic aortic plaques detected by noninvasive magnetic resonance imaging.
OBJECTIVES: We sought to elucidate the effects of 20-mg versus 5-mg atorvastatin on thoracic and abdominal aortic plaques. BACKGROUND: Regression of thoracic aortic plaques by simvastatin was demonstrated using magnetic resonance imaging (MRI). However, the effects of different doses of statin have not been assessed. METHODS: Using MRI, we investigated the effects of 20-mg versus 5-mg atorvastatin on thoracic and abdominal aortic plaques in 40 hypercholesterolemic patients who were randomized to receive either dose. Treatment effects were evaluated as changes in vessel wall thickness (VWT) and vessel wall area (VWA) of atherosclerotic lesions from baseline to 12 months of treatment. RESULTS: The 20-mg dose induced a greater low-density lipoprotein (LDL) cholesterol reduction than did the 5-mg dose (-47% vs. -34%, p < 0.001). Although 20 mg and 5 mg reduced C-reactive protein (CRP) levels (-47% and -28%), the degree of CRP reduction did not differ between the two doses. The 20-mg dose reduced VWT and VWA of thoracic aortic plaques (-12% and -18%, p < 0.001), whereas 5 mg did not (+1% and +4%). Regarding abdominal aortic plaques, even 20 mg could not reduce VWT or VWA (-1% and +3%), but instead progression was observed with 5-mg treatment (+5% and +12%, p < 0.01). Notably, the degree of plaque regression in thoracic aorta correlated with LDL cholesterol (r = 0.64) and CRP (r = 0.49) reductions. Although changes in abdominal aortic plaques only weakly correlated with LDL cholesterol reduction (r = 0.34), they correlated with age (r = 0.41). CONCLUSIONS: One-year 20-mg atorvastatin treatment induced regression of thoracic aortic plaques with marked LDL cholesterol reduction, whereas it resulted in only retardation of plaque progression in abdominal aorta. Thoracic and abdominal aortic plaques may have different susceptibilities to lipid lowering.
Br J Ophthalmol. 2005 Mar;89(3):275-9.
Thomas PB, Albini T, Giri RK, See RF, Evans M, Rao NA.
Doheny Eye Institute, DVRC 211, 1450 San Pablo Street, Los Angeles CA 90033, USA.
The effects of atorvastatin in experimental autoimmune uveitis.
AIM: To investigate the effect of atorvastatin (Lipitor), a commonly used drug for dyslipidaemia in experimental autoimmune uveitis (EAU). METHODS: 48 B10-RIII mice were immunised with human interphotoreceptor retinoid binding protein (IRBP) peptide p161-180. They were divided into three groups of 16 each and treated orally once daily for 14 days; group one received phosphate buffered saline (control group), group two received 1 mg/kg of atorvastatin (low dose group), and group three received 10 mg/kg (high dose). On day 14 lymph nodes, spleens, and right eyes were harvested. RNA was extracted from lymph nodes for RNase protection assay (RPA) to determine proinflammatory (IL-1alpha and IL-1beta), Th1 (TNF-alpha, IL-2, IL-12), and Th2 (IL-4, IL-5, and IL-10) cytokine levels. Protein was extracted from spleens for western blot to detect the expression of phosphorylated signal transducer and activator of transcription (STAT) 4 and STAT6. The severity of inflammation in enucleated eyes was graded by a masked observer. Paired t test was performed for the mean difference in histological scoring between treated groups and the immunised control group. RESULTS: Surprisingly, atorvastatin did not modulate the immune response. The proinflammatory cytokines, IL-1alpha and IL-1beta, and Th1 cytokines, TNF-alpha and IL-2, were upregulated equally in control and atorvastatin treated groups. IL-12 and Th2 cytokines were not upregulated in all three groups. Western blot analysis showed high levels of phosphorylated STAT4, but not STAT6 protein in the control and atorvastatin treated groups. Mean differences in histological scoring between treated groups and the immunised control group were not statistically significant. CONCLUSIONS: Atorvastatin treatment had no effect on Th1 and Th2 cytokine transcription. Although histological grading suggested mildly decreased inflammation in the high dose treated group, the equivalence of cytokine expression in all groups suggests that the statins may not modulate IRBP induced uveoretinitis.
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Drug category:Antilipemic agents
 Lipitor scientific update
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