938 resultados para Phase-Ii


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Lorazepam (LOR) is a 3-hydroxy-1,4-benzodiazepine that is chiral and undergoes enantiomerization at room temperature. In humans, about 75% of the administered dose of LOR is excreted in the urine as its 30-glucuronide. CE-MS with negative ESI was used to confirm the presence of LOR-30-glucuronide in urines that stemmed from a healthy individual who ingested 1 or 2 mg LOR, whereas free LOR could be detected in extracts prepared from enzymatically hydrolyzed urines. As the 30-glucuronidation reaction occurs at the chiral center of the molecule, two diastereoisomers can theoretically be formed, molecules that can no longer interconvert. The stereoselective formation of LOR glucuronides in humans and in vitro was investigated. MEKC analysis of extracts of the nonhydrolyzed urines suggested the presence of the two different LOR glucuronides in the urine. The formation of the same two diastereoisomers was also observed in vitro employing incubations of LOR with human liver microsomes in the presence of uridine 5'-diphospho-glucuronic acid as coenzyme. The absence of other coenzymes excluded the formation of phase I or other phase II metabolites of LOR. Both results revealed a stereoselectivity, one diastereoisomer being formed in a higher amount than the other. After enzymatic hydrolysis using beta-glucuronidase, these peaks could not be detected any more. Instead, LOR was monitored. Analysis of the extracts prepared from enzymatically hydrolyzed urines by MEKC in the presence of 2-hydroxypropyl-beta-CD revealed the enantiomerization process of LOR (observation of two peaks of equal magnitude connected with a plateau zone). The data presented provide for the first time the evidence of the stereoselectivity of the LOR glucuronidation in humans.

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Having determined in a phase I study the maximum tolerated dose of high-dose ifosfamide combined with high-dose doxorubicin, we now report the long-term results of a phase II trial in advanced soft-tissue sarcomas. Forty-six patients with locally advanced or metastatic soft-tissue sarcomas were included, with age <60 years and all except one in good performance status (0 or 1). The chemotherapy treatment consisted of ifosfamide 10 g m(-2) (continuous infusion for 5 days), doxorubicin 30 mg m(-2) day(-1) x 3 (total dose 90 mg m(-2)), mesna and granulocyte-colony stimulating factor. Cycles were repeated every 21 days. A median of 4 (1-6) cycles per patient was administered. Twenty-two patients responded to therapy, including three complete responders and 19 partial responders for an overall response rate of 48% (95% CI: 33-63%). The response rate was not different between localised and metastatic diseases or between histological types, but was higher in grade 3 tumours. Median overall survival was 19 months. Salvage therapies (surgery and/or radiotherapy) were performed in 43% of patients and found to be the most significant predictor for favourable survival (exploratory multivariate analysis). Haematological toxicity was severe, including grade > or =3 neutropenia in 59%, thrombopenia in 39% and anaemia in 27% of cycles. Three patients experienced grade 3 neurotoxicity and one patient died of septic shock. This high-dose regimen is toxic but nonetheless feasible in multicentre settings in non elderly patients with good performance status. A high response rate was obtained. Prolonged survival was mainly a function of salvage therapies.

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Colonisation of the gastrointestinal tract by anaerobic bacteria, protozoa, trematodes, cestodes and/or nematodes and other infectious pathogens, including viruses, represents a major cause of morbidity and mortality in Africa, South America and southeast Asia, as well as other parts of the world. Nitazoxanide is a member of the thiazolide class of drugs with a documented broad spectrum of activity against parasites and anaerobic bacteria. Moreover, the drug has recently been reported to have a profound activity against hepatitis C virus infection. In addition, nitazoxanide exhibits anti-inflammatory properties, which have prompted clinical investigations for its use in Crohn's disease. Studies with nitazoxanide derivatives have determined that there must be significantly different mechanisms of action acting on intracellular versus extracellular pathogens. An impressive number of clinical studies have shown that the drug has an excellent bioavailability in the gastrointestinal tract, is fast acting and highly effective against gastrointestinal bacteria, protozoa and helminthes. A recent Phase II study has demonstrated viral response (hepatitis C) to monotherapy, with a low toxicity and an excellent safety profile over 24 weeks of treatment. Pre-clinical studies have indicated that there is a potential for application of this drug against other diseases, not primarily affecting the liver or the gastrointestinal tract.

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GOALS OF WORK: The aim of this study was to evaluate pain intensity and the application of the WHO guidelines for cancer pain treatment in patients with prostate cancer treated at Swiss cancer centers. MATERIALS AND METHODS: We analyzed a series of five multicenter phase II clinical trials which examined the palliative effect of different chemotherapies in patients with advanced hormone-refractory prostate carcinoma. Of 170 patients, 1,018 visits were evaluable for our purpose, including ratings of pain intensity by patients and prescribed analgesics. MAIN RESULTS: No or mild pain was indicated by patients in 36 to 55% of the visits, more than mild pain in 30 to 46%. In 21% of the visits, the WHO pain treatment criteria (treatment according to one of the three steps; oral, rectal or transdermal application of the main dose; administration on a regular schedule) were fulfilled, and the Cleeland index was positive according to all recommendations. In 6% of the visits, neither the WHO criteria were fulfilled nor was the Cleeland index positive. This indicates insufficient pain treatment not following the WHO guidelines and that the prescribed analgesics were not sufficiently potent for the rated pain intensity. CONCLUSIONS: In this selective Swiss sample, the standard of analgesic treatment is high. However, there is still scope for improvement. This cannot solely be solved by improving the knowledge of the physicians. Programs to change the patients' attitude towards cancer pain, training to improve the physicians' communication skills, and institutional changes may be promising strategies.

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Cerebral vasospasm is still the most important cause of death and disability after rupture of intracranial aneurysms. The therapeutic strategies in the treatment of subarachnoid hemorrhage induced vasospasm vasospasm include four groups: 1) prevention of vasospasm; 2) reversion of vasospasm; 3) improvement of cerebral perfusion; and 4) neuroprotection and rescue therapies. Recent experimental studies allowed the design of phase II clinical studies which demonstrated positive results with medications and compounds such as statins (simvastatin and pravastatin) and endothelin-1 receptor antagonists (clasozentan). Moreover, experimental and clinical evidences showed the advantages of early cerebrospinal fluid drainage, intrathecal administration of NO-donors, effects of Ca2+ protein kinase inhibitor (Fasudil) and catecholamines on the cerebral vessels. This review article summarizes the stage of investigation of these medications and therapeutic strategies which will be relevant in the treatment of cerebral vasospasm.

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In 1992, it was shown that monoclonal antibodies blocking alpha(4)-integrins prevent the development of experimental autoimmune encephalomyelitis, an animal model for multiple sclerosis (MS). As alpha(4)beta(1)-integrin was demonstrated to mediate the attachment of immune-competent cells to inflamed brain endothelium in experimental autoimmune encephalomyelitis, the therapeutic effect was attributed to the inhibition of immune cell extravasation and inflammation in the central nervous system. This novel therapeutic approach was rapidly and successfully translated into the clinic. The humanized anti-alpha(4)-integrin antibody natalizumab demonstrated an unequivocal therapeutic effect in preventing relapses and slowing down the pace of neurological deterioration in patients with relapsing-remitting MS in phase II and phase III clinical trials. The occurrence of 3 cases of progressive multifocal leukoencephalopathy in patients treated with natalizumab led to the voluntary withdrawal of the drug from the market. After a thorough safety evaluation of all patients receiving this drug in past and ongoing studies for MS and Crohn's disease, natalizumab again obtained approval in the US and the European Community. A treatment targeting leukocyte trafficking in MS has now re-entered the clinic. Further thorough evaluation is necessary for a better understanding of the risk-benefit balance of this new treatment option for relapsing MS. In this review, we discuss the basic mechanism of action, key clinical results of clinical trials and the emerging indication of natalizumab in MS.

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One of the original ocean-bottom time-lapse seismic studies was performed at the Teal South oil field in the Gulf of Mexico during the late 1990’s. This work reexamines some aspects of previous work using modern analysis techniques to provide improved quantitative interpretations. Using three-dimensional volume visualization of legacy data and the two phases of post-production time-lapse data, I provide additional insight into the fluid migration pathways and the pressure communication between different reservoirs, separated by faults. This work supports a conclusion from previous studies that production from one reservoir caused regional pressure decline that in turn resulted in liberation of gas from multiple surrounding unproduced reservoirs. I also provide an explanation for unusual time-lapse changes in amplitude-versus-offset (AVO) data related to the compaction of the producing reservoir which, in turn, changed an isotropic medium to an anisotropic medium. In the first part of this work, I examine regional changes in seismic response due to the production of oil and gas from one reservoir. The previous studies primarily used two post-production ocean-bottom surveys (Phase I and Phase II), and not the legacy streamer data, due to the unavailability of legacy prestack data and very different acquisition parameters. In order to incorporate the legacy data in the present study, all three poststack data sets were cross-equalized and examined using instantaneous amplitude and energy volumes. This approach appears quite effective and helps to suppress changes unrelated to production while emphasizing those large-amplitude changes that are related to production in this noisy (by current standards) suite of data. I examine the multiple data sets first by using the instantaneous amplitude and energy attributes, and then also examine specific apparent time-lapse changes through direct comparisons of seismic traces. In so doing, I identify time-delays that, when corrected for, indicate water encroachment at the base of the producing reservoir. I also identify specific sites of leakage from various unproduced reservoirs, the result of regional pressure blowdown as explained in previous studies; those earlier studies, however, were unable to identify direct evidence of fluid movement. Of particular interest is the identification of one site where oil apparently leaked from one reservoir into a “new” reservoir that did not originally contain oil, but was ideally suited as a trap for fluids leaking from the neighboring spill-point. With continued pressure drop, oil in the new reservoir increased as more oil entered into the reservoir and expanded, liberating gas from solution. Because of the limited volume available for oil and gas in that temporary trap, oil and gas also escaped from it into the surrounding formation. I also note that some of the reservoirs demonstrate time-lapse changes only in the “gas cap” and not in the oil zone, even though gas must be coming out of solution everywhere in the reservoir. This is explained by interplay between pore-fluid modulus reduction by gas saturation decrease and dry-frame modulus increase by frame stiffening. In the second part of this work, I examine various rock-physics models in an attempt to quantitatively account for frame-stiffening that results from reduced pore-fluid pressure in the producing reservoir, searching for a model that would predict the unusual AVO features observed in the time-lapse prestack and stacked data at Teal South. While several rock-physics models are successful at predicting the time-lapse response for initial production, most fail to match the observations for continued production between Phase I and Phase II. Because the reservoir was initially overpressured and unconsolidated, reservoir compaction was likely significant, and is probably accomplished largely by uniaxial strain in the vertical direction; this implies that an anisotropic model may be required. Using Walton’s model for anisotropic unconsolidated sand, I successfully model the time-lapse changes for all phases of production. This observation may be of interest for application to other unconsolidated overpressured reservoirs under production.

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Intussusceptive angiogenesis is a novel mode of blood vessel formation and remodeling, which occurs by internal division of the preexisting capillary plexus without sprouting. In this study, the process is demonstrated in developing chicken eye vasculature and in the chorioallantoic membrane by methylmethacrylate (Mercox) casting, transmission electron microscopy, and in vivo observation. In a first step of intussusceptive angiogenesis, the capillary plexus expands by insertion of numerous transcapillary tissue pillars, ie, by intussusceptive microvascular growth. In a subsequent step, a vascular tree arises from the primitive capillary plexus as a result of intussusceptive pillar formation and pillar fusions, a process we termed "intussusceptive arborization." On the basis of the morphological observations, a 4-step model for intussusceptive arborization is proposed, as follows: phase I, numerous circular pillars are formed in rows, thus demarcating future vessels; phase II, formation of narrow tissue septa by pillar reshaping and pillar fusions; phase III, delineation, segregation, growth, and extraction of the new vascular entity by merging of septa; and phase IV, formation of new branching generations by successively repeating the process, complemented by growth and maturation of all components. In contrast to sprouting, intussusceptive angiogenesis does not require intense local endothelial cell proliferation; it is implemented primarily by rearrangement and attenuation of the endothelial cell plates. In summary, transcapillary pillar formation, ie, intussusception, is a central and probably widespread process, which plays a role not only in capillary network growth and expansion (intussusceptive microvascular growth), but also in vascular plexus remodeling and tree formation (intussusceptive arborization).

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Neutropenic enterocolitis is a potentially fatal complication of myeloablative chemotherapy in patients with acute myeloid leukemia. Omega-3 polyunsaturated fatty acids (PUFA) are precursors of potent anti-inflammatory prostaglandins. Our aim was to explore the safety and effectiveness of omega-3 PUFA added to parenteral nutrition in protecting leukemia patients from severe enterocolitis. Fourteen patients with acute myeloid leukemia who received omega-3 PUFA in a Phase II trial were compared with 66 consecutive control patients not getting this intervention. We performed crude and adjusted comparisons, using inverse probability of treatment weighting for adjusted analysis, and blind outcome assessment to minimize assessor bias. Primary outcome was severe enterocolitis (≥Grade 3). The crude odds ratio of Grade 3 colitis or higher was 1.36 (95% CI 0.37 to 4.96, P = 0.64), and the adjusted odds ratio was 0.79 (95% CI 0.35 to 1.78, P = 0.57). There was little evidence to suggest differences between groups in serious adverse events and overall mortality. Our results provide little evidence that addition of omega-3 PUFA is beneficial in this condition. Routine treatment with omega-3 PUFA is currently not warranted.

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BACKGROUND Evidence exists that a farming environment in childhood may provide protection against atopic respiratory disease. In the GABRIEL project based in Poland and Alpine regions of Germany, Austria and Switzerland, we aimed to assess whether a farming environment in childhood is protective against allergic diseases in Poland and whether specific exposures explain any protective effect. METHODS In rural Poland, 23 331 families of schoolchildren completed a questionnaire enquiring into farming practices and allergic diseases (Phase I). A subsample (n = 2586) participated in Phase II involving a more detailed questionnaire on specific farm exposures with objective measures of atopy. RESULTS Farming differed between Poland and the Alpine centres; in the latter, cattle farming was prevalent, whereas in Poland 18% of village farms kept ≥1 cow and 34% kept ≥1 pig. Polish children in villages had lower prevalences of asthma and hay fever than children from towns, and in the Phase II population, farm children had a reduced risk of atopy measured by IgE (aOR = 0.72, 95% CI 0.57, 0.91) and skin prick test (aOR = 0.65, 95% CI 0.50, 0.86). Early-life contact with grain was inversely related to the risk of atopy measured by IgE (aOR = 0.66, 95% CI 0.47, 0.92) and appeared to explain part of the farming effect. CONCLUSION While farming in Poland differed from that in the Alpine areas as did the exposure-response associations, we found in communities engaged in small-scale, mixed farming, there was a protective farming effect against objective measures of atopy potentially related to contact with grain or associated farm activities.

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OBJECTIVES To assess the feasibility of using volumetric capnography in spontaneously breathing small infants and its ability to discriminate between infants with and without bronchopulmonary dysplasia (BPD). STUDY DESIGN Lung function variables for 231 infants (102 term, 52 healthy preterm, 77 BPD), matched for post-conceptional age of 44 weeks, were collected. BPD was defined as supplemental oxygen requirement at 36 weeks post-menstrual age. Tidal breath-by-breath volume capnograms were obtained by mainstream capnography. The capnographic slope of phase II (SII) and slope of phase III (SIII) were calculated and compared between study groups. The effect of BPD, tidal volume (VT), respiratory rate (RR), and prematurity on the magnitude of the slopes was assessed. RESULTS SII was steeper in infants with BPD (100 ± 28/L) compared with healthy preterm (88 ± 22/L; P = .007) and term infants (79 ± 18/L; P < .001), but this finding was attributed to differences in VT, RR, and gestational age. SIII was steeper in the BPD group (26.8 ± 14.1/L) compared with healthy preterm (16.2 ± 6.2/L; P < .001) and term controls (14.8 ± 5.4/L; P < .001). BPD was a significant predictor of SIII independently of VT, RR, and gestational age. The ability of SIII to discriminate between BPD and controls was significantly higher compared with lung clearance index (area under the curve 0.83 vs 0.56; P < .001). CONCLUSIONS Volumetric capnography may provide valuable information regarding functional lung alterations related to BPD and might be considered as an alternative to more involved lung function techniques for monitoring chronic lung disease during early infancy.

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2-Methiopropamine [1-(thiophen-2-yl)-2-methylaminopropane, 2-MPA], a thiophene analogue of methamphetamine, is available from online vendors selling "Research chemicals." The first samples were seized by the German police in 2011. As it is a recreational stimulant, its inclusion in routine drug screening protocols should be required. The aims of this study were to identify the phase I and II metabolites of 2-MPA in rat and human urine and to identify the human cytochrome-P450 (CYP) isoenzymes involved in its phase I metabolism. In addition, the detectability of 2-MPA in urine samples using the authors' well-established gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-linear ion trap-mass spectrometry (LC-MS(n)) screening protocols was also evaluated. The metabolites were isolated from rat and human urine samples by solid-Phase extraction without or following enzymatic cleavage of conjugates. The phase I metabolites, following acetylation, were separated and identified by GC-MS and/or liquid chromatography-high-resolution linear ion trap mass spectrometry (LC-HR-MS(n)) and the phase II metabolites by LC-HR-MS(n). The following Major metabolic pathways were proposed: N-demethylation, hydroxylation at the side chain and at the thiophene ring, and combination of these transformations followed by glucuronidation and/or sulfation. CYP1A2, CYP2C19, CYP2D6, and CYP3A4 were identified as the major phase I metabolizing enzymes. They were also involved in the N-demethylation of the analogue methamphetamine and CYP2C19, CYP2D6, and CYP3A4 in its ring hydroxylation. Following the administration of a typical user's dose, 2-MPA and its metabolites were identified in rat urine using the authors' GC-MS and the LC-MS(n) screening approaches. Ingestion of 2-MPA could also be detected by both protocols in an authentic human urine sample.

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This paper reports on the results of a research project, on comparing one virtual collaborative environment with a first-person visual immersion (first-perspective interaction) and a second one where the user interacts through a sound-kinetic virtual representation of himself (avatar), as a stress-coping environment in real-life situations. Recent developments in coping research are proposing a shift from a trait-oriented approach of coping to a more situation-specific treatment. We defined as real-life situation a target-oriented situation that demands a complex coping skills inventory of high self-efficacy and internal or external "locus of control" strategies. The participants were 90 normal adults with healthy or impaired coping skills, 25-40 years of age, randomly spread across two groups. There was the same number of participants across groups and gender balance within groups. All two groups went through two phases. In Phase I, Solo, one participant was assessed using a three-stage assessment inspired by the transactional stress theory of Lazarus and the stress inoculation theory of Meichenbaum. In Phase I, each participant was given a coping skills measurement within the time course of various hypothetical stressful encounters performed in two different conditions and a control group. In Condition A, the participant was given a virtual stress assessment scenario relative to a first-person perspective (VRFP). In Condition B, the participant was given a virtual stress assessment scenario relative to a behaviorally realistic motion controlled avatar with sonic feedback (VRSA). In Condition C, the No Treatment Condition (NTC), the participant received just an interview. In Phase II, all three groups were mixed and exercised the same tasks but with two participants in pairs. The results showed that the VRSA group performed notably better in terms of cognitive appraisals, emotions and attributions than the other two groups in Phase I (VRSA, 92%; VRFP, 85%; NTC, 34%). In Phase II, the difference again favored the VRSA group against the other two. These results indicate that a virtual collaborative environment seems to be a consistent coping environment, tapping two classes of stress: (a) aversive or ambiguous situations, and (b) loss or failure situations in relation to the stress inoculation theory. In terms of coping behaviors, a distinction is made between self-directed and environment-directed strategies. A great advantage of the virtual collaborative environment with the behaviorally enhanced sound-kinetic avatar is the consideration of team coping intentions in different stages. Even if the aim is to tap transactional processes in real-life situations, it might be better to conduct research using a sound-kinetic avatar based collaborative environment than a virtual first-person perspective scenario alone. The VE consisted of two dual-processor PC systems, a video splitter, a digital camera and two stereoscopic CRT displays. The system was programmed in C++ and VRScape Immersive Cluster from VRCO, which created an artificial environment that encodes the user's motion from a video camera, targeted at the face of the users and physiological sensors attached to the body.

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Tumors comprising the spectrum of hemangiopericytoma/ malignant solitary fibrous tumor (HPC/SFT) are thought to arise from fibroblasts and represent a small subset of soft tissue sarcomas. Surgery is typically the treatment of choice for localized disease, with reported 10-year overall survival rates of 54-89% after complete surgical resection. However, for the approximately 20% of HPC/SFT patients who eventually develop local recurrences and/or distant metastases, options for effective treatment are limited and are poorly defined. Alternative therapeutic options are therefore needed for improved palliation and disease control. We hypothesize that HPC/SFT are a spectrum of soft tissue tumors with unique clinical, pathological, and molecular makeup and clinical behavior. HPC/SFT respond to unique therapeutic agents that specifically target aberrations specific to these tumors. We retrospectively reviewed the characteristics and the clinical outcomes for all HPC/SFT patients whose tumor specimens have been reviewed at the MD Anderson Cancer Center from January 1993 to June 2007 by a MD Anderson pathologist and were treated at the institution with available electronic medical records. We identified 128 patients, 79 with primary localized disease and 49 with recurrent and/or metastatic disease. For the 23 patients with advanced HPC/SFT who received adriamycin-based, gemcitabine based, or paclitaxel chemotherapy as first- or second-line therapy, the overall RECIST response rate was 0%. Most patients achieved a brief duration of disease stabilization on chemotherapy, with median progression-free survival (PFS) period of 4.6 months. For the 14 patients with advanced HPC/SFT who received temozolomide and bevacizumab systemic therapy, the overall RECIST response rate was 14%, with the overall Choi response rate of 79%. The median PFS for the cohort was 9.7 months with a median 6-month progression free rate of 78.6%. The most frequently observed toxic effect of temzolomide-bevacizumab therapy was myelosuppression. We have designed a phase II study to evaluate the safety and efficacy of temozolomide-bevaciumab in locally advanced, recurrent, and metastatic HPC/SFT in a prospective manner. Combination therapy with temozolomide and bevacizumab may be a potentially clinically beneficial regimen for advanced HPC/SFT patients.

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BACKGROUND Statins have anti-inflammatory and immunomodulatory properties in addition to lipid-lowering effects. OBJECTIVES To report the 12-month extension of a phase II trial evaluating the efficacy, safety and tolerability of atorvastatin 40 mg/d added to interferon beta-1b (IFNB-1b) in relapsing-remitting multiple sclerosis (RRMS). METHODS In the randomized, multicenter, parallel-group, rater-blinded core study, 77 RRMS patients started IFNB-1b. At month three they were randomized 1∶1 to receive atorvastatin 40 mg/d or not in addition to IFNB-1b until month 15. In the subsequent extension study, patients continued with unchanged medication for another 12 months. Data at study end were compared to data at month three of the core study. RESULTS 27 of 72 patients that finished the core study entered the extension study. 45 patients were lost mainly due to a safety analysis during the core study including a recruitment stop for the extension study. The primary end point, the proportion of patients with new lesions on T2-weighted images was equal in both groups (odds ratio 1.926; 95% CI 0.265-14.0007; p = 0.51). All secondary endpoints including number of new lesions and total lesion volume on T2-weighted images, total number of Gd-enhancing lesions on T1-weighted images, volume of grey and white matter, EDSS, MSFC, relapse rate, number of relapse-free patients and neutralizing antibodies did not show significant differences either. The combination therapy was well tolerated. CONCLUSIONS Atorvastatin 40 mg/day in addition to IFNB-1b did not have any beneficial effects on RRMS compared to IFNB-1b monotherapy over a period of 24 months.