207 resultados para Tacrolimus
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PURPOSE: To report a case of conjunctival intraepithelial neoplasia in a patient treated with tacrolimus after liver transplantation for hepatic carcinoma. METHODS: Description of the initial clinical presentation of a patient, tumor management, and 15-month follow-up. RESULTS: A 70-year-old man presented with a conjunctival intraepithelial neoplasia that developed on the site of a preexisting pterygium. After total surgical removal and additional application of mitomycin, local tumor control was achieved. CONCLUSIONS: We describe a case of intraepithelial conjunctival neoplasia in a patient treated with systemic tacrolimus. Local tumor control was achieved at 15 months after appropriate surgical management.
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Purpose: In this prospective randomized study efficacy and safety of two immunosuppressive regimens (Tac, MMF, Steroids vs. CsA, MMF, Steroids) after Lung Transplantation were compared. Primary objective was the incidence of bronchiolitis obliterans syndrome (BOS). Secondary objectives were incidence of acute rejection and infection, survival and adverse events. 248 patients with a complete 3 year follow-up were included in the analysis. Methods and Materials: Patients were randomized to treatment group A: Tac (0.01-0.03 mg/kg/d iv-0.05-0.3 mg/kg/d po) or B: CsA (1-3 mg/kg/d iv-2-8 mg/kg/d po). MMF dose was1-4 mg/d in both groups. No induction therapy was given. Patients were stratified for cystic fibrosis. Intention to treat analysis was performed in patients who were switched to a different immunosuppressive regimen. Results: 3 of 123 Tac patients and 41 of 125 CsA patients were switched to another immunosuppressive regimen and were analyzed as intention to treat. Three year follow-up data of the complete patient cohort were included in this final analysis. Groups showed no difference in demographic data. Kaplan Meier analysis revealed significantly less BOS in Tac treated patients (p=0.033, log rank test, pooled over strata). Cox regression showed a twice as high risk for BOS in the CsA group (factor 2.003). Incidence of acute rejection was 67.5% (Tac) and 75.2% (CsA) (p=0.583). One- and 3-year-survival-rates were not different (85.4% Tac vs. 88.8% CsA, and 80.5% Tac vs. 83.2% CsA, p=n.s.). Incidence of infections and renal failure was similar (p=n.s.). Conclusions: Tac significantly reduced the risk for BOS after 3 years in this intention to treat analysis. Both regimens have a good immunosuppressive potential and offer a similar safety profile with excellent one and three year survival rates. Acute rejection rates were similar in both groups. Incidence of infections and renal failure showed no difference.
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BACKGROUND: Chronic lung allograft dysfunction, which manifests as bronchiolitis obliterans syndrome (BOS), is recognized as the primary cause of morbidity and mortality after lung transplantation. In this study we assessed the efficacy and safety of two de novo immunosuppression protocols to prevent BOS. METHODS: Our study approach was a multicenter, prospective, randomized (1:1) open-label superiority investigation of de novo tacrolimus vs cyclosporine, with both study arms given mycophenolate mofetil and prednisolone after lung transplantation. Cytolytic induction therapy was not employed. Patients were stratified at entry for cystic fibrosis. Primary outcome was incidence of BOS 3 years after transplant (intention-to-treat analysis). Secondary outcomes were survival and incidence of acute rejection, infection and other adverse events. RESULTS: Group demographic data were well matched: 110 of 124 tacrolimus vs 74 of 125 cyclosporine patients were treated per protocol (p < 0.01 by chi-square test). Cumulative incidence of BOS Grade ≥1 at 3 years was 11.6% (tacrolimus) vs 21.3% (cyclosporine) (cumulative incidence curves, p = 0.037 by Gray's test, pooled over strata). Univariate proportional sub-distribution hazards regression confirmed cyclosporine as a risk for BOS (HR 1.97, 95% CI 1.04 to 3.77, p = 0.039). Three-year cumulative incidence of acute rejection was 67.4% (tacrolimus) vs 74.9% (cyclosporine) (p = 0.118 by Gray's test). One- and 3-year survival rates were 84.6% and 78.7% (tacrolimus) vs 88.6% and 82.8% (cyclosporine) (p = 0.382 by log-rank test). Cumulative infection rates were similar (p = 0.91), but there was a trend toward new-onset renal failure with tacrolimus (p = 0.09). CONCLUSIONS: Compared with cyclosporine, de novo tacrolimus use was found to be associated with a significantly reduced risk for BOS Grade ≥1 at 3 years despite a similar rate of acute rejection. However, no survival advantage was detected.
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BACKGROUND: C iclosporine ( CsA), Tacrolimus (Tcl) and Infliximab (IFX) are effective rescue therapies in steroidrefractory ulcerative colitis (UC). Comparative studies are however m issing. M ETHOD: T his i s the retrospective analysis of treatment outcome for oral Tcl (n=27, initially 0.05mg/Kg twice daily, aiming for serum trough levels of 5-10 n g/mL), i ntravenous C sA ( n=23, 2 mg/kg/daily a nd then o ral CsA 5mg/kg/daily) and IFX ( n=43, 5 mg/kg intravenously at week 0, 2, 6 and then every 8 weeks) in patients with s teroid r efractory moderate to s evere UC enrolled i n the SWISS IBD cohort s tudy. After successful rescue therapy with Tcl o r C sA, t hiopurine m aintenance therapy or maintenance therapy with Tcl (in Tcl pretreated patients) was introduced. The endpoints analyzed steroid free r emission r ate (on the basis of m odified Truelove- Witts severity index (MTWSI)) and number of colectomies after 6 m onths. R ESULTS: A t 6 months, 26% ( 7/27) o f patients treated with T cl r emained i n steroid free remission (MTWSI score ≤4) compared to 30 % (7/23) on 18 droplets to the same extend under the linoleic acid treat, whereas lipid hydrolysis or loss was significantly increased in Huh-7 WT cells after 24h. Conclusions: Chronic alcohol feeding in obese, insulin-resistant rats exerts significant and synergistic effects on PNPLA3 mRNA expression, which correlated with triglyceride content. In v itro experiments suggest that PNPLA3 expression depends on the t ypes of d ietary f atty acids with polyunsaturated fatty a cids i nducing a nd monounsaturated fatty a cids inhibiting PNPLA3 mRNA. I148M polymorphism of PNPLA3 l eads to attenuation o f lipolytic processes resulting in fat accumulation in the cell. 20 CsA and 58% ( 27/41) o f patients t reated w ith IFX ( Tcl & CsA vs I FX p = 0 .018). S ignificant m ore patients had primary non response, loss of response or severe adverse events i n the CsA cohort ( 61%, 1 4/23) c ompared to Tcl cohort (33.3 % , 9/27), and IFX cohort (30%, 1 3/43) (p= 0.037). Colectomy rate was significantly higher after CsA (17.4 %, 4/23) compared to Tcl (3.7 %, 1/27) or IFX (2.3 %, 1/43) (p= 0.047).CONCLUSION: After s ix m onth, rescue therapy with I FX h ad t he l owest c olectomy r ate, significantly h igher steroid free r emission rate, a nd t he lowest rate of non-response, loss of response and severe adverse events compared to CsA or Tcl rescue treatment.
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BACKGROUND: Calcineurin inhibitors (cyclosporine (CsA) and tacrolimus (Tcl)) and the anti-TNF-antibody infliximab (IFX) are established therapeutic options in steroid-refractory ulcerative colitis (UC). In acute severe UC failing steroids, a randomized trial showed an 85% short term response to CsA or IFX, with avoidance of colectomy. Comparative responses to the three drugs in outpatients with steroid-refractory UC are unknown. METHOD: Response to treatment in patients with steroid-refractory moderate to severe UC was retrospectively studied in three cohorts of patients: Cohort A (n=24) treated with oral Tcl (initially 0.05mg/kg twice daily, aiming for serum trough levels of 5-10 ng/mL); Cohort B (n=19) treated with intravenous CsA 2mg/kg/daily and then oral CsA 5mg/kg/daily; Cohort C. (n= 41) treated with IFX (5mg/kg intravenously at week 0, 2, 6 and then every 8 weeks). After successful rescue therapy with Tcl or CsA, thiopurine maintenance therapy was introduced. The endpoint was evaluation of clinical remission or response at week 6, on the basis of modified Truelove-Witts severity index (MTWSI). RESULTS: After 6 weeks, 42% (10/24) of patients treated with Tcl achieved remission (MTWSI score ≤4) compared to 47% (9/ 19) on CsA and 66% (27/41) of patients treated with IFX (Tcl & CsA vs IFX p=0.127). Clinical response (decrease of MTWSI score of more than 4 points) at week 6 was reached in 25% (6/24) patients on Tcl, compared to 11% (2/19) on CsA and 20% (8/41) given IFX (p=0.484). Subgroup analysis showed the highest rates of remission in those with moderate steroid-refractory UC treated with IFX: 29% (2/7) in Tcl group compared to 50% (2/4) in CsA group and 76 % (19/25) in IFX group (Tcl &CsA vs IFX p= 0.058) Patients with severe colitis showed similar rates of remission in all three groups: 47% (8/17) on Tcl, 47% (7/ 15) on CsA and 50% (8/16) on IFX (p= 0.700). Colectomy within 6 weeks occurred in 4% (1/24) after Tcl, 5% (1/19) after CsA and 0% (0/41) after IFX. Adverse effects in the first 6 weeks were observed in 13% (3/24) on Tcl, 26% (5/19) on CsA, and 10% (4/41) on IFX (p=0.224) CONCLUSION: No significant differences in response, remission, colectomy rate or adverse events between the three agents were found, although the study is too small for definitive conclusions. There are intriguing differences, with potentially greater response to IFX in moderate, steroid-refractory UC.
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PURPOSE: A misleading blood tacrolimus concentration (BTC) value caused by the contamination of a central venous catheter previously used for tacrolimus administration is described. SUMMARY: A 59-year-old woman with severe chronic obstructive pulmonary disease successfully underwent double lung transplantation. In the intensive care unit, she received a continuous i.v. infusion of tacrolimus from days 1 to 5 after transplantation through the distal lumen of a polyurethane triple-lumen central venous catheter. The catheter lumen was flushed twice a day with 0.9% sodium chloride injection. The proximal lumen was used for blood sampling after being flushed; the first 10 mL of blood was discarded. BTCs determined in whole blood one, four, and five days after transplantation were within the therapeutic range of 5-15 ng/mL. On day five the patient was transferred to the thoracic surgery ward and was switched to oral tacrolimus 1.5 mg twice daily. The BTC on day 6 was unexpectedly high at 134.5 ng/mL. The patient's clinical status was normal, and no signs of tacrolimus toxicity were observed. On day 7, blood samples were drawn from a peripheral vein and simultaneously through the central venous catheter. Although the central venous catheter had not been exposed to tacrolimus during the preceding two days, it yielded blood with a BTC eight times higher than the BTC in blood from the peripheral vein (41.4 ng/mL versus 5.1 ng/mL). CONCLUSION: The collection of blood from a central venous catheter lumen that had been used for tacrolimus administration resulted in a BTC about eight times higher than what was measured in peripheral blood.
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A 59-year-old kidney recipient was diagnosed with a late onset of severe chronic inflammatory demyelinating polyradiculoneuropathy and almost fully recovered after stopping tacrolimus and one course of intravenous immunoglobulin treatment. Unique features of this patient are the unusually long time lapse between initiation of tacrolimus and the adverse effect (10 years), a strong causality link and several arguments pointing toward an inflammatory etiology. When facing new neurological signs and symptoms in graft recipients, it is important to bear in mind the possibility of a drug-induced adverse event. Discontinuation of the suspect drug and immunomodulation are useful treatment options.
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Introduction. - Le traitement de la polymyosite et de l'atteinte pulmonaireassociées au syndrome des anti-synthétases peut serévéler difficile. Le tacrolimus est proposé en cas d'échec aux autresimmunosuppresseurs. Néanmoins, contrairement aux patientsgreffés, son utilisation dans cette indication est mal codifiée. Nousrapportons les cas de 2 patients traités efficacement par tacrolimus.Cas Clinique. - Cas 1. Il s'agit d'un homme de 44 ans originaire deMadagascar, chez qui le diagnostic de syndrome des anti-synthétasesest posé devant l'association mains de mécanicien, polymyosite,manifestation de raynaud et présence d'anticorps anti Jo1fortement positifs à 281U (norme < 50U). Les différents traitementsproposés (prednisone 1 mg/kg, méthotrexate, azathioprine,rituximab et Immunoglobulines IV) ne permettent pas de contrôlerla situation avec un pic des CK à 24 000 U/l au décours des Ig IV.Une IRM réalisée alors retrouve une activité inflammatoire intensedes compartiments antérieurs et postérieurs des cuisses des 2 côtés.Finalement un traitement de tacrolimus est proposé en augmentationprogressive. L'efficacité du traitement est mesurée par l'évolutiondes CK qui passent en quelques mois de 24 000 U/l à 300 U/lsous une dose de 6 mg/j de tacrolimus et d'une amélioration parIRM spectaculaire. Malheureusement, suite à un épisode de déshydratation,le patient développe une insuffisance rénale aigüemodérée (créatinine à 124 _mol/l contre 89 auparavant) non réversibleaprès réhydratation. Pour stabiliser la fonction rénale le tacrolimusest baissé à 4 mg/jour au prix d'une réapparition des douleursmusculaires et d'une ré-ascension des CK à 1 000 U/l. Cas 2. Il s'agitd'une patiente de 61 ans chez qui le diagnostic de syndrome desanti-synthétases est posé devant l'association atteinte articulaire,mains de mécanicien, atteinte musculaire, pneumopathie interstitiellediffuse et forte positivité des Ac anti JO1 à 252 U. Une associationtacrolimus et prednisone est rapidement proposée en raison del'atteinte pulmonaire. Malheureusement la patiente développe uneinsuffisance rénale progressive sous 9 mg/j de tacrolimus et malgréune réponse favorable sur le plan pulmonaire, le traitement estinterrompu avec amélioration de la fonction rénale.Discussion. - Le tacrolimus est un traitement immunosuppresseuranalogue à la ciclosporine, avec une action 100 fois supérieure. Ilinhibe l'activation et la prolifération des cellules T et sa principaletoxicité est rénale. Traitement puissant, il a montré son efficacitédans les atteintes pulmonaires sévères liées à un syndrome desanti-synthétases1.2. Les pneumologues le connaissent bien et chezles patients greffés, la surveillance de l'efficacité et de la toxicité dutraitement se fait grâce à des mesures du taux résiduel. Néanmoinsdans le cadre du syndrome des anti-synthétases les mesures de surveillancesont moins bien codifiées. Même si l'efficacité du tacrolimussemble excellente dans les formes musculaires etpulmonaires sévères, nos 2 cas nous rendent attentifs sur l'importanced'une surveillance rapprochée de la fonction rénale.Conclusion. - Le tacrolimus est un puissant immunosuppresseur quipeut être proposé aux patients souffrant de manifestations sévèresd'un syndrome des anti-synthétases. Une dose standard n'existe paset il faut être attentif à sa toxicité rénale.
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Ce travail de recherche a été réalisé dans le laboratoire de pharmacologie clinique, au Centre Hospitalier Universitaire Sainte-Justine, à Montréal. C'est une étude rétrospective basée sur le suivi thérapeutique du Tacrolimus prescrit chez les enfants après transplantation hépatique. Ce suivi est nécessaire car le Tacrolimus possède une importante variabilité pharmacocinétique inter et intra-individuelle ainsi qu'un index thérapeutique très étroit. Actuellement, l'individualisation des doses prescrites est basée sur la mesure de la concentration de base - du médicament dans le sang (C0), mais des études récentes montrent que cette mesure ne reflète pas précisément l'exposition du Tacrolimus dans l'organisme chez les enfants. Le meilleur reflet de cette exposition est la mesure de l'aire sous la courbe (AUC). Cependant, cette dernière implique la mesure de multiples concentrations tout au long de l'intervalle entre 2 doses de médicament (Tacrolimus: 12 heures) ce qui est long, cher et impraticable en ambulatoire. De nouvelles méthodes utilisant un nombre limité de prélèvements ont donc été développées pour prédire au mieux cette AUC. Ce sont les "Limited sampling strategies" ou LSS. La plupart de ces LSS pour le Tacrolimus ont été développées et validées chez des patients transplantés adultes et leur application directe chez les transplantés pédiatriques n'est pas possible en raison de différences importantes au niveau des paramètres pharmacocinétiques du médicament entre ces deux populations. Aussi, le but de ce travail était de développer et valider, pour la première fois, des LSS chez les enfants transplantés hépatiques. Pour cela, une analyse de 36 profils pharmacocinétiques de 28 patients transplantés hépatiques âgés de 0.4- 18.5 ans a été effectuée. Tous les profils ont été réalisés au Centre Hospitalier Universitaire Sainte-Justine entre janvier 2007 et janvier 2009. Les LSS comportant au maximum 4 mesures de concentration ont été développées en utilisant une analyse de régression multiple. Parmi tous les modèles obtenus, cinq ont été sélectionnés sur la base de critères précis puis validés selon la méthode décrite par Sheiner et Beal.¦Les résultats montrent que ces cinq modèles peuvent prédire l'AUC du Tacrolimus avec une précision cliniquement acceptable de ± 15% alors que la C0 présente la plus faible corrélation avec l'AUC.¦En conclusion, cette étude confirme que la C0 ne permet pas de prédire de manière efficace l'exposition du Tacrolimus dans l'organisme dans notre population de patients pédiatriques contrairement aux LSS analysées qui offrent une méthode pratique et fiable. Par ailleurs, en permettant d'obtenir une estimation précise et simplifiée de l'AUC complète du Tacrolimus chez les patients, ces LSS ouvrent la porte à de futures études prospectives visant à mieux définir l'AUC cible du médicament et à déterminer si le suivi basé sur la mesure de l'AUC est plus efficace et plus sûr que celui basé sur la mesure de la C0.
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Objectives: This study aims to evaluate the effectiveness of periodontal therapy combined with tacrolimus in the suppression of gingival overgrowth (GO) and the effect on GO of changing from cyclosporin A to tacrolimus. Patients and Methods: Sixteen renal transplant patients, averaging 52 years of age, whose kidney function was stable and were receiving treatment with cyclosporin A, were randomly assigned to one of two groups. In the experimental group, patients were instructed in oral hygiene and underwent periodontal treatment, whereas in the control group, only oral hygiene instructions were given. After the first visit and the change of medication from cyclosporine to tacrolimus in both groups, periodic clinical revisions were carried out for 3 months in order to assess the evolution of GO. Results: All patients showed a progressive decrease in GO. There were no statistically significant differences between the two groups (p>0.05). A greater decrease in GO occurred within the first month after changing the medication. Conclusions: No improved effectiveness in reducing GO was observed for periodontal therapy in combination with tacrolimus. Tacrolimus is an alternative to cyclosporine when attempting to avoid GO in patients with kidney transplants
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The use of immunosuppressive drugs in transplanted patients is associated with the development of diabetes, possibly due to β-cell toxicity. To better understand the mechanisms leading to post-transplant diabetes, we investigated the actions of prolonged exposure of isolated human islets to therapeutical levels of tacrolimus (Tac) or cyclosporin A (CsA). Islets were isolated from the pancreas of multiorgan donors by enzymatic digestion and density gradient centrifugation. Functional, survival and molecular studies were then performed after 4 days of incubation with therapeutical concentrations of Tac or CsA. Glucose-induced insulin secretion was significantly decreased in Tac, but not in CsA exposed islets, which was associated with a reduction of the amount of insulin granules as shown by electron microscopy. The percentage of apoptotic β-cells was higher in Tac than CsA exposed islets. Microarray experiments followed by Gene Set Enrichment Analysis revealed that gene expression was more markedly affected upon Tac treatment. In conclusion, Tac and CsA affect features of beta-cell differently, with several changes occurring at the molecular level.
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Current evidences show that tacrolimus could be a good therapeutic option in patients non-responsive to first-line treatments and even it could become one of the first-line drugs for treating MG. Our study will try to determine the effectivity and safety of tacrolimus in 190 myasthenia gravis patients with suboptimal response to azathioprine: after 12 months of treatment they will be randomized to continue with azathioprine or they will be switched to tacrolimus. Patients will follow the allocated treatment during 14 months and the response will be assessed as well as adverse effectsPURPOSE: To compare azathioprine vs. tacrolimus effectivity and safety in MG patients with suboptimal response to azathioprine at 12 monthsDESIGN: A 14 months multicenter, prospective, randomized, double blind, head to head clinical trial
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OBJETIVO: Avaliar em dois momentos distintos da regeneração hepática a influência do Tacrolimus sobre o fenômeno da regeneração hepática desencadeada pela ressecção de 70% do parênquima hepático em ratos plenamente desenvolvidos. MÉTODOS: Utilizaram-se 40 ratos Wistar com peso médio de 510,08 g ± 11.66 g distribuidos aleatoriamente em dois grupos de 20, cada grupo subdividido em dois subgrupos conforme o dia da morte após a hepatectomia. De acordo com o grupo os animais receberam por gavagem solução aquosa de Tacrolimus 0,1 mg/kg/dia ou solução salina no mesmo volume. Após três dias de pré-terapia todos foram submetidos à hepatectomia de 70% pela ressecção dos lobos hepáticos mediano e lateral esquerdo que foram pesados para posterior cálculo da regeneração hepática pela fórmula de Kwon. Vinte e quatro horas ou sete dias após a hepatectomia, 10 animais de cada grupo foram mortos, os fígados remanescentes (regenerados) foram pesados e amostrados para realização de índice mitótico por hematoxilina-eosina e estudo imunoistoquímico com os marcadores PCNA e Ki-67. RESULTADOS: Os animais que receberam tacrolimus mostraram índice maior de regeneração hepática, atingindo significância estatística quando comparado ao subgrupo de animais mantidos com placebo quando analisados pelos parâmetros: fórmula de Kwon, índice mitótico e marcador PCNA. A tendência para o marcador Ki-67 foi idêntica aos outros parâmetros mas não alcançou significância estatística. CONCLUSÃO: A imunossupressão com tacrolimus possui efeito estimulatório no processo de regeneração hepática desencadeado pela hepatectomia 70% em ratos Wistar adultos, plenamente desenvolvidos.
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OBJETIVO: verificar se o tacrolimus administrado em ratos, em vigência de pancreatite induzida pela L-Arginina, interfere nos níveis séricos da amilase e glicose e no padrão histológico do parênquima pancreático. MÉTODOS: quarenta ratos Wistar foram distribuídos em quatro grupos com 10 ratos cada. Grupo controle (C), grupo tacrolimus (T), grupo pancreatite (P) e grupo pancreatite-tacrolimus (PT). Foram avaliados os níveis séricos de amilase, glicose e tacrolimus e feitas avaliações histológicas do pâncreas, A indução de pancreatite foi feita pela inoculação de L-Arginina na dose de 500mg/100g de peso corporal por via intraperitoneal e o tratamento com tacrolimus na dose de 1ìg/kg por via subcutânea durante quatro dias. RESULTADOS: a amilasemia estava mais elevada (p=0,0000) nos grupos PT, T e P do que no grupo controle. A média do grupo PT foi maior (p=0,0009) que a do grupo T, mas não diferiu (p=0,6802) da média do grupo P. Entre os grupos P e T não houve diferença (p=0,2568). Não houve diferença nas médias de glicemia entre os grupos (p=0,4920) e os níveis séricos de tacrolimus foram similares nos grupos PT e T (p=0,7112). Não ocorreram alterações histológicas nos grupos T e C e não ocorreu hemorragia no pâncreas dos ratos dos grupos P e PT. No grupo P, em 30% não se observou edema, em 20% observou-se a forma leve e em 50%, a moderada; quanto à infiltração inflamatória, em 80% moderada e em 20% não ocorreu, e a atrofia do parênquima foi de 60% moderada e 40% acentuada. No grupo PT, houve ocorrência de edema, infiltração inflamatória e atrofia do pâncreas em todos os ratos. CONCLUSÃO: o tratamento pelo tacrolimus induziu aumento nos níveis séricos de amilase em ratos normais, não alterou a glicemia nem o padrão histológico do parênquima pancreático. Na vigência de pancreatite induzida pela L-Arginina o tacrolimus induziu edema, infiltração inflamatória e atrofia com maior gravidade no parênquima pancreático.
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OBJETIVO: avaliar a toxicidade do tacrolimus sobre o desenvolvimento embrionário em ratas tratadas durante o período de trânsito tubário. MÉTODOS: sessenta ratas Wistar foram distribuídas em quatro grupos (15 animais cada), que receberam diferentes doses de tacrolimus por via intragástrica: (T1) 1,0 mg/kg/dia, (T2) 2,0 mg/kg/dia e (T3) 4,0 mg/kg/dia. O grupo controle (C) recebeu água destilada. As ratas foram observadas diariamente para detectar sinais clínicos de toxicidade. O tratamento foi realizado do primeiro ao quinto dia de gestação. As seguintes variáveis maternas foram analisadas: peso corporal, de ovários, fígados e rins, consumo de alimento, número de corpos lúteos, implantes, fetos vivos e mortos e índice de implantação. Os fetos e placentas foram pesados e os primeiros foram observados para detectar malformações externas. Estatística: análise de variância (ANOVA), uma via, seguida de teste de Dunnett (alfa=0,05). RESULTADOS: não ocorreram indícios clínicos de toxicidade materna, tais como perda de peso, redução do consumo de alimento ou do peso de órgãos (p>0,05). Também não houve diferença significativa no peso corporal dos fetos (C: 1,8±0,6; T1: 2,2±0,5; T2: 1,9±0,5 e T3: 2,0±0,5 g) e de placentas (C: 1,6±0,4; T1: 1,5±0,4; T2: 1,8±0,4 e T3: 1,6±0,4 g), com p>0,05. Nenhuma malformação externa foi detectada. CONCLUSÕES: a administração de tacrolimus a ratas prenhes durante o período de trânsito tubário não parece ter qualquer efeito tóxico e materno ou embrionário.