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Objectives To better understand patients' and pharmacists' preferences for and experiences with changes in pill appearance (size, shape, color, and markings). Study design Cross-sectional. Methods We conducted independent national surveys of patients 50 years and older taking generic drugs for depression, diabetes, epilepsy, HIV, hyperlipidemia, or hypertension and of licensed pharmacists practicing in chain, franchise, or independent pharmacies. Responses were collected between January and April 2016. Results Of 1000 patient respondents (30% response rate), most reported experiencing changes in pill appearance (51%) and preferred to be notified about them (82%), but less than half recalled being notified (verbally: 36%; via sticker: 45%). Among patients who reported experiencing a change, 12% reported stopping their medication or using it less frequently. Of 710 pharmacist respondents (33% response rate), many reported changes in pill appearance occurring frequently in their pharmacies (47% reported that changes occurred 6 or more times per month) and more than three-fourths reported notifying patients about them often (verbally: 88%; via sticker: 77%). Conclusions Our findings reveal opportunities to improve patients' experiences with pill appearance changes through better notification practices and patient education.

BACKGROUND: Generic versions of a drug can vary in appearance, which can impact adherence. OBJECTIVE: To assess the preferences, perceptions, and responses of patients who experienced a change in the appearance of a generic medication. DESIGN: Cross-sectional survey of patients from a large commercial health plan. PARTICIPANTS: Adults receiving generic versions of lisinopril, fluoxetine, lamotrigine, or simvastatin who experienced a change in the color or shape of their pills between March 2014 and November 2015. MAIN MEASURES: Likert-scale responses to questions concerning perceptions of generic drug safety and effectiveness, reliance on and preferences for pill appearance, and responses to pill appearance changes. Multivariable logistic regression-modeled predictors of seeking advice and adjusting use following a pill appearance change. KEY RESULTS: Of 814 respondents (response rate = 41%), 72% relied on pill appearance to ensure they took the correct medication. A similar percentage wanted their pills to remain the same color (72%), shape (71%), and size (75%) upon refill, but 58% would not have paid a $1 premium on a $5 co-pay to ensure such consistency. Most respondents (86%) wanted their pharmacists to notify them about pill appearance changes, but only 37% recalled such notification; 21% thought they received the wrong medication, and 8% adjusted medication use. Younger respondents (18–33 vs. 50–57 years) were more likely to seek advice (odds ratio [OR] = 1.91; 95% confidence interval [CI],1.02–3.59), and respondents with lower household income ( $100,000) were more likely to adjust medication use (OR = 3.40; 95% CI,1.09–10.67). CONCLUSIONS: Requiring uniform pill appearance may help increase adherence but presents challenges. Standardized pharmacy notification and education policies may be a more feasible short-term solution. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s11606-018-4791-1) contains supplementary material, which is available to authorized users.

Purpose The purpose of this study was to provide an algorithm for generic brittleness and to elucidate the demographic factors that anticipate generic brittleness for patients with epilepsy. Methods This exploratory, observational, and nontherapeutic study was conducted in patients with epilepsy who were routinely followed at the University of Maryland epilepsy outpatient clinic in Baltimore, Maryland. Patients were taking at least one antiepileptic drug (AED) for treatment of epilepsy. Based on patient interview and medical history, 12 demographic factors were collected. Each patient was assessed to be either generic brittle (GB) or not GB. Demographic factors were subjected to binary logistical regression and other statistical tests, to elucidate determinants of GB status. Results N = 148 patients completed the study. An algorithm to define whether a patient was GB or not GB was devised. The two elements that defined GB status are as follows: patient opinion about generics and (if needed) whether patients were currently taking brand or generic of their most problematic AED. About 40% of patients were GB. From binary logistical regression, two demographic factors that contributed to patients being GB were whether a patient was currently taking a problem AED and total number of current medications for a patient, with odds ratios of 4.06 (95% confidence interval [CI] from 1.53 to 10.81) and 1.10 (95% CI from 1.003 to 1.21), respectively. Of the patients on a problem AED, 46.9% were GB, while only 18.2% of patients not currently on a problem AED were GB. The total number of current medications ranged from 1 to 22, with mode of four medications. From regression, for each additional medication that a patient took, the odds of being GB increased 1.10-fold. Although patient seizure and adverse event history was not employed to define GB status, being GB was associated with less seizure control and greater adverse events. Conclusions An algorithm for generic brittleness was derived, and about 40% of patients were GB, usually due to prior history of a switch problem. Two demographic factors favored patients being GB: whether the patient was currently taking a problem AED and the total number of current medications.

Background: Accumulation of systemically administered nanoparticles (NPs) in lymph nodes has been exploited clinically for diagnostic imaging (e.g., USPIOs for lymph node metastasis) and therapeutic applications (e.g., vaccine delivery). However, the combination of diagnostic and therapeutic functionalities into a single theranostic NP has obliged undesirable trade-offs between either the imaging or drug delivery of the NP and their specific accumulation in lymph nodes. To overcome these trade-offs, we conducted a screen of various lipid-based theranostic NPs focusing on differing NP design and their resulting pharmacokinetic behaviours in healthy and diseased lymph node models. Methods: Lipid-based theranostic NPs with varying physicochemical characteristics (e.g., formulation, size and morphology, surface targeting, etc.) were prepared with positron emitting Cu-64 and administered systemically at equivalent NP doses in healthy and diseased rodent models (i.e., mice and rats). NP types were assessed for time-dependent accumulation in major lymph node basins via non-invasive whole-body PET/MR imaging at two or more timepoints per animal. 72-hours post-injection the animals were sacrificed, and lymph nodes and major organs were excised for gamma counting and pathological evaluation. Pharmacokinetic behaviour of NPs in healthy versus diseased lymph nodes were calculated in individual animals and in naïvely pooled datasets using non-compartmental analysis. Results: Preliminary analysis identified a leading NP candidate with specific lymph node targeting in healthy and diseased rodents: a discoidal, 35-nm peptide-targeted HDL-mimetic. In comparison with a spherical, 100-nm PEGylated NP, the discoidal NP obtained greater absolute (%ID) and relative (%ID/g) amounts of injected dose in anatomically matched lymph nodes than the spherical NP, regardless of lymph node pathology. At greatest measured concentration in healthy lymph nodes, typically 24-hpi, the differences between the discoidal and spherical NPs were on average 3-fold greater (2.893 vs. 0.864, %ID/g). Differences in other pharmacokinetic parameters such as AUC (%ID/g*h) and MRT (h) were equally pronounced. Conclusions: Our preliminary analysis uncovered a discoidal, peptide-targeted HDL-mimetic with remarkable accumulation in lymph nodes of healthy and diseased models. Future investigations will focus on the biochemical and cellular mechanisms underlying their unique lymphatic pharmacokinetics. These preliminary results provide key insights for design of theranostic NPs for non-invasive imaging and staging lymph node pathologies, and for applications in delivery of therapeutics to lymph nodes following systemic administration. Citation Format: Michael S. Valic, Mark Zheng, Lili Ding, Michelle Lai, Chris J. Zhang, Tina Ye, Jenny Ma, Michael Halim, Pamela Schimmer, Wenlei Jiang, Juan Chen, Gang Zheng. Lymph node accumulation of theranostic lipid-based nanoparticles in healthy and diseased models: Preliminary results comparing nanoparticle morphology and targeting [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 307.

We sought to examine rates of clinical outcomes among patients before and after market introduction of generic versions of five drugs approved using product-specific equivalence determinations. We used data from a large national insurer to identify patients who initiated a study (acarbose tablets, salmon calcitonin nasal spray, enoxaparin injection, vancomycin capsules, venlafaxine extended-release tablets) or control drug (nateglinide, glimepiride, alendronate, fondaparinux, metronidazole, sertraline, paroxetine) in each calendar month between 2003 and 2012 and to determine rates of claims-based proxies for lack of effectiveness outcomes following initiation. We used segmented time-series analyses to evaluate level (short-term) and slope (longer-term) changes in outcomes upon introduction of a generic study or control drug. Among study drugs, we observed three increases (one with p

A patient was denoted to be generic brittle (GB) if they had a negative opinion about generics (e.g. prior history of a switch problem) or took the innovator brand of their most problematic anti-epileptic drug (AED) when generic was available. The aim of this hypothesis-generating study was to assess possible genetic and physiologic differences between GB and not GB patients with epilepsy. Patients (n = 148) with epilepsy were previously characterized as being either GB or not GB. Blood was collected from each subject for genotyping and physiologic testing. Genotyping for 24 single nucleotide polymorphisms (SNPs) and two copy number variants (CNVs) was performed across 12 genes in each patient. Forty-four physiologic tests were conducted in each patient. Chi square analysis was performed to assess for associations between genotyping results and GB status, as well as between physiologic test results and GB status. No SNP or CNV discriminated GB status in genetic analysis (genotype or allele frequency). Physiologic test results in this study were not associated with GB status. Questions from neurologists and patients about generics is frequently based on applicability of generic drug standards to individual subjects. However, findings here in patients with epilepsy did not uncover genetic or physiologic reasons that explained which patients were GB and which were not GB.

Sirolimus, an immunosuppressive agent used in renal transplantation, can prevent allograft rejection. Identification of the therapeutic index (the ratio of minimum toxic concentration to minimum therapeutic concentration) for immunosuppresants is necessary to optimize the care of patients and set standards for bioequivalence evaluation of sirolimus products. However, the therapeutic index for sirolimus has been inconsistently defined, potentially because of inconsistencies in sirolimus exposure-response relationships.The authors used retrospective therapeutic drug monitoring data from the electronic health records of patients treated in a tertiary health care system from 2008 to 2014 to (1) develop a population pharmacokinetic (PK) model, (2) use the model to simulate sirolimus concentrations, and (3) characterize the exposure-response relationship. Using Wilcoxon rank-sum and Fisher exact tests, the authors determined relationships between sirolimus exposure and adverse events (AEs) (anemia, leukopenia, thrombocytopenia, hyperlipidemia, and decline in renal function) and the composite efficacy end point of graft loss or rejection.The developed 2-compartment population PK model showed appropriate goodness of fit. In a late-phase (12 months), postrenal transplant population of 27 inpatients, the authors identified statistically significant relationships between 83 simulated peak and trough sirolimus concentrations and outcomes: graft loss or rejection (P = 0.018) and decline in renal function (P = 0.006), respectively.Use of therapeutic drug monitoring results and PK modeling permitted correlation of sirolimus concentrations with graft loss or rejection and decline in renal function. However, the method was limited in its assessment of other AEs. To better evaluate sirolimus exposure-response relationships, the method should be applied to a larger sample of newly transplanted patients with a higher propensity toward AEs or efficacy failure.

Objective We sought to examine rates of clinical outcomes among patients before and after market introduction of generic versions of five drugs approved using product-specific equivalence determinations.

Purpose The purpose of the study was to assess if any antiepileptic drug (AED) was associated with patients being generic brittle (GB) and if any specific AED caused – and was not merely associated with – more frequent switch problems. Methods Chi square and binary logistical regression analysis were performed, using a previously described study in patients with epilepsy who were routinely followed at the University of Maryland epilepsy outpatient clinic in Baltimore, Maryland. Determination of generic brittleness mirrored clinical practice and included patient opinion about generic formulations, usually based on a history of worsened seizures or side effects with prior AED formulation switching. The dataset included a total of 148 patients, who took 30 different AED formulations. Patients collectively took 530 AED formulation products. Results Taking lamotrigine immediate release (IR) tablets was associated with a greater probability of being GB and tended to cause more frequent switch problems. Interestingly, six AEDs – Vimpat tablet, carbamazepine IR tablet, phenobarbital (any formulation), gabapentin capsule, Lyrica capsules, and phenytoin (any formulation) – were associated with a reduced probability of being GB, although perhaps not through greater efficacy and tolerability, or better formulation quality. Since tablet and capsule appearance may influence patient perceptions and clinical outcomes, it was observed that the six AEDs less associated with being GB also tended to have fewer generics, and hence possibly lessen treatment uncertainties from the patient perspective. A patient taking more AEDs had significantly increased odds of having a switch problem. An additional observation was that, when a generic was available for their most problematic AED, GB patients took a generic AED only 50% of the time, while not GB patients took a generic AED all the time. Conclusions Taking lamotrigine IR tablets was associated with a greater probability of being GB and tended to cause more frequent switch problems than other AEDs in this cohort of patients. Six AEDs were associated with a reduced probability of being GB. The lower number of different generics for these six drugs may result in greater patient certainty in medication identity, due to greater consistency in medication color, shape, and size, and hence less generic skepticism or generic brittleness. Also, patients taking more AEDs showed increased odds of a switch problem.

The purpose of this study was to determine the intrapatient (within the same patient) variability of tacrolimus in adherent patients. Daily tacrolimus trough levels were obtained at home using dried blood spot technology in kidney and liver transplant recipients. Patients were randomized to receive 3 formulations of tacrolimus, each for two 1-week periods. Adherence was monitored by patient diary, pill counts, and use of the Medication Event Monitoring System (MEMS). Variability was quantified as the coefficient of variation (CV). Comparison of CV between groups was by independent t test or one-way ANOVA as appropriate. The population was found to be adherent with a rate of 99.9% with a mean interval between the evening and morning dose of tacrolimus of 11.86 hours. The median CV for the entire population was 15.2% (range 4.8%-110%). There were no differences in CV by allograft type or tacrolimus formulation. The multivariate analysis did not identify any demographic characteristics associated with a CV > 30%. In a highly adherent population, tacrolimus did not display high intrapatient variability. Given the association between IPV and poor allograft outcomes, future studies are needed to quantitate the influence of adherence and establish target IPV goals.

Head and neck cancer is the fifth most common type of cancer worldwide and remains challenging for effective treatment due to the proximity to critical anatomical structures in the head and neck region, which increases the probability of toxicity from surgery and radiotherapy, and therefore emphasizes the importance of maximizing the targeted ablation. We have assessed the effectiveness of porphysome nanoparticles to enhance fluorescence and photoacoustic imaging of head and neck tumors in rabbit and hamster models. In addition, we evaluated the effectiveness of this agent for localized photothermal ablative therapy of head and neck tumors. We have demonstrated that porphysomes not only enabled fluorescence and photoacoustic imaging of buccal and tongue carcinomas, but also allowed for complete targeted ablation of these tumors. The supremacy of porphysome-enabled photothermal therapy over surgery to completely eradicate primary tumors and metastatic regional lymph node while sparing the adjacent critical structures' function has been demonstrated for the first time. This study represents a novel breakthrough that has the potential to revolutionize our approach to tumor diagnosis and treatment in head and neck cancer and beyond.

Background Although the generic drug approval process has a long-term successful track record, concerns remain for approval of narrow therapeutic index generic immunosuppressants, such as tacrolimus, in transplant recipients. Several professional transplant societies and publications have generated skepticism of the generic approval process. Three major areas of concern are that the pharmacokinetic properties of generic products and the innovator (that is, “brand”) product in healthy volunteers may not reflect those in transplant recipients, bioequivalence between generic and innovator may not ensure bioequivalence between generics, and high-risk patients may have specific bioequivalence concerns. Such concerns have been fueled by anecdotal observations and retrospective and uncontrolled published studies, while well-designed, controlled prospective studies testing the validity of the regulatory bioequivalence testing approach for narrow therapeutic index immunosuppressants in transplant recipients have been lacking. Thus, the present study prospectively assesses bioequivalence between innovator tacrolimus and 2 generics in individuals with a kidney or liver transplant. Methods and findings From December 2013 through October 2014, a prospective, replicate dosing, partially blinded, randomized, 3-treatment, 6-period crossover bioequivalence study was conducted at the University of Cincinnati in individuals with a kidney (n = 35) or liver transplant (n = 36). Abbreviated New Drug Applications (ANDA) data that included manufacturing and healthy individual pharmacokinetic data for all generics were evaluated to select the 2 most disparate generics from innovator, and these were named Generic Hi and Generic Lo. During the 8-week study period, pharmacokinetic studies assessed the bioequivalence of Generic Hi and Generic Lo with the Innovator tacrolimus and with each other. Bioequivalence of the major tacrolimus metabolite was also assessed. All products fell within the US Food and Drug Administration (FDA) average bioequivalence (ABE) acceptance criteria of a 90% confidence interval contained within the confidence limits of 80.00% and 125.00%. Within-subject variability was similar for the area under the curve (AUC) (range 12.11–15.81) and the concentration maximum (Cmax) (range 17.96–24.72) for all products. The within-subject variability was utilized to calculate the scaled average bioequivalence (SCABE) 90% confidence interval. The calculated SCABE 90% confidence interval was 84.65%–118.13% and 80.00%–125.00% for AUC and Cmax, respectively. The more stringent SCABE acceptance criteria were met for all product comparisons for AUC and Cmax in both individuals with a kidney transplant and those with a liver transplant. European Medicines Agency (EMA) acceptance criteria for narrow therapeutic index drugs were also met, with the only exception being in the case of Brand versus Generic Lo, in which the upper limits of the 90% confidence intervals were 111.30% (kidney) and 112.12% (liver). These were only slightly above the upper EMA acceptance criteria limit for an AUC of 111.11%. SCABE criteria were also met for the major tacrolimus metabolite 13-O-desmethyl tacrolimus for AUC, but it failed the EMA criterion. No acute rejections, no differences in renal function in all individuals, and no differences in liver function were observed in individuals with a liver transplant using the Tukey honest significant difference (HSD) test for multiple comparisons. Fifty-two percent and 65% of all individuals with a kidney or liver transplant, respectively, reported an adverse event. The Exact McNemar test for paired categorical data with adjustments for multiple comparisons was used to compare adverse event rates among the products. No statistically significant differences among any pairs of products were found for any adverse event code or for adverse events overall. Limitations of this study include that the observations were made under strictly controlled conditions that did not allow for the impact of nonadherence or feeding on the possible pharmacokinetic differences. Generic Hi and Lo were selected based upon bioequivalence data in healthy volunteers because no pharmacokinetic data in recipients were available for all products. The safety data should be interpreted in light of the small number of participants and the short observation periods. Lastly, only the 1 mg tacrolimus strength was utilized in this study. Conclusions Using an innovative, controlled bioequivalence study design, we observed equivalence between tacrolimus innovator and 2 generic products as well as between 2 generic products in individuals after kidney or liver transplantation following current FDA bioequivalence metrics. These results support the position that bioequivalence for the narrow therapeutic index drug tacrolimus translates from healthy volunteers to individuals receiving a kidney or liver transplant and provides evidence that generic products that are bioequivalent with the innovator product are also bioequivalent to each other. Trial registration ClinicalTrials.gov NCT01889758., In a randomized 3-treatment crossover clinical trial, Rita Alloway of the University of Cincinnati and colleagues establish bioequivalence between 3 versions of the drug tracolimus (a brand name and 2 disparate generics) in kidney and liver transplant recipients., Author summary Why was this study done? Consensus documents developed by professional transplantation societies worldwide have cautioned the use of generic immunosuppressants such as tacrolimus in individuals with a solid organ transplant. Reasons have included repeated switching between innovator (that is, “brand” products) and generics and among different generics, especially when not controlled by physicians. There was uncertainty in the transplant community as to whether tacrolimus generics that are bioequivalent to the innovator are also bioequivalent to each other. For market approval, generic drug products of the narrow therapeutic index drug tacrolimus had to be studied only in healthy individuals and not in the much more complex organ transplant population. What did the researchers do and find? We performed a randomized, prospective, 3-treatment, 6-period, crossover, replicate dose study in individuals with a kidney or liver transplant. Thirty-five individuals with a kidney transplant and 36 individuals with a liver transplant receiving tacrolimus were studied to compare the tacrolimus time concentration profiles of 3 different products in their blood: namely, Innovator (Prograf), Generic Hi (Sandoz), and Generic Lo (Dr. Reddy) 1.0 mg tacrolimus capsules. Generic products were selected based upon pharmacokinetic data from healthy volunteer studies since bioequivalence data were not available in individuals with an organ transplant. We observed bioequivalence based on average bioequivalence and scaled average bioequivalence criteria in individuals after kidney or liver transplant between tacrolimus innovator and the 2 generics on the US market as well as between the 2 generics. What do these findings mean? Similar tacrolimus exposure is expected in individuals with a kidney or liver transplant when receiving Prograf, Sandoz generic, or Dr. Reddy’s generic tacrolimus.

This review summarizes the current FDA practice in developing risk- and evidence-based product-specific bioequivalence guidances for antiepileptic drugs (AEDs). FDA’s product-specific guidance (PSG) for AEDs takes into account the therapeutic index of each AED product. Several PSGs for AEDs recommend fully replicated studies and a reference-scaled average bioequivalence (RS-ABE) approach that permit the simultaneous equivalence comparison of the mean and within-subject variability of the test and reference products. The PSGs for AEDs published by FDA reflect the agency’s current thinking on the bioequivalence studies and approval standards for generics of AEDs. Bioequivalence between brand and generic AED products demonstrated in controlled studies with epilepsy patients provides strong scientific support for the soundness of FDA bioequivalence standards.

Importance Switching between generic antiepileptic drugs is a highly debated issue that affects both clinical care and overall health care costs. Objective To evaluate the single-dose pharmacokinetic bioequivalence of 3 (1 branded and 2 generic drugs) on-market, immediate-release lamotrigine drug products. Design, Setting, and Participants The Equivalence Among Antiepileptic Drug Generic and Brand Products in People With Epilepsy (EQUIGEN) single-dose study is a crossover, prospective, sequence-randomized, replicate pharmacokinetic study conducted at 5 US academic epilepsy centers. Fifty adults (≥18 years) with epilepsy who were taking concomitant antiepileptic drugs and not currently receiving lamotrigine were enrolled between July 18, 2013, and January 19, 2015. Every participant was randomly assigned to 1 of 3 equivalent sequences, each comprising 6 study periods, during which they had blood draws before and after medication administration. Forty-nine participants were included in intention-to-treat analyses. Interventions Participants received a single 25-mg dose of immediate-release lamotrigine at the start of each period, with the branded and the 2 most disparate generic products each studied twice. Lamotrigine was selected as the antiepileptic drug of interest because of its wide use, publications indicating problems with generic switches, and complaints to the US Food and Drug Administration regarding generic products. Both participants and study personnel were blinded to the specific generic products selected. Main Outcomes and Measures The primary outcome was bioequivalence between products. Maximum plasma concentration (Cmax) and area under the concentration–time curve (AUC) were compared, and average bioequivalence (ABE) was established if the 90% CIs of the ratios of the 2 products were within equivalence limits (80%-125%). Results Of the 50 randomized participants, 49 (98%) received all 3 lamotrigine products and completed at least 3 pharmacokinetic assessments and 46 (92%) completed all 6 pharmacokinetic assessments. Among the 49 participants, 28 (57%) were men and 21 (43%) were women, 42 (86%) self-identified as white, and 46 (16) years was the mean (SD) age. The 3 drug products were considered bioequivalent because the 90% CIs were within equivalence limits (lowest and highest CI limits for Cmax, 92.6% and 110.4%; for AUC 0-96 , 96.9% and 101.9%). Replicate testing demonstrated no significant differences in within-subject variability across the 3 products (likelihood ratios, χ 2 2 for log-transformed variables: AUC 0-96 , 2.58; Cmax, 0.64; and AUC 0-∞ , 4.05; P ≥ .13) and that the 3 products were also bioequivalent according to scaled ABE and individual bioequivalence criteria with no subject × formulation interaction (Cmax, 0.00; AUC 0-96 , 0.54; and AUC 0-∞ , 0.36; P ≥ .76). Conclusions and Relevance This study provides evidence that the disparate lamotrigine products studied are bioequivalent when tested in people with epilepsy taking concomitant antiepileptic drugs. Trial Registration clinicaltrials.gov Identifier:NCT01733394

Small changes in bioavailability of narrow therapeutic index (NTI) drugs can alter clinical outcomes, raising concern over generic NTI substitution. We surveyed pharmacists to identify their perceptions of generic NTI drugs, their frequency of performing generic NTI substitution, and predictors of this behavior. Of 710 respondents (33% response rate), 87% perceived generic NTI drugs as effective as their brand-name versions and 94% as safe. Whereas 82% almost always performed generic NTI substitution for initial prescriptions, only 60% did for refills. Pharmacists in non-chain settings (odds ratio (OR) = 2.37; 95% confidence interval (CI) = 1.40-4.02), in practice longer (per year OR = 1.04; 95% CI = 1.02-1.06), in states with affirmative patient consent laws (OR = 1.88; 95% CI = 1.06-3.32), and in states with NTI-specific substitution requirements (OR = 1.95; 95% CI = 1.16-3.26) were more likely not to substitute initial prescriptions. Education of non-chain and veteran pharmacists and elimination of affirmative patient consent and NTI-specific substitution requirements could increase generic NTI substitution.

There is evidence to suggest that, in acute liver failure (ALF), brain ammonia and proinflammatory cytokines may act synergistically to cause brain edema and its complications (intracranial hypertension, brain herniation). However, the molecular mechanisms involved remain to be established. In order to address this issue, semi-quantitative RT-PCR was used to measure the expression of genes coding for astrocytic proteins with an established role in cell volume regulation in cerebral cortical astrocytes exposed to toxic agents previously identified in experimental and clinical ALF. Such agents include ammonia, the proinflammatory cytokine interleukin-1beta (IL-1beta) and combinations of the two. Exposure of cultured astrocytes to recombinant IL-1beta (but not ammonia) resulted in increased expression of aquaporin-4 (AQP-4). Both ammonia and proinflammatory mediators led to decreased expression of glial fibrillary acidic protein (GFAP), a cytoskeletal protein, but these effects were not additive. On the other hand, heme oxygenase-1 (HO-1) and inducible nitric oxide synthase (iNOS) expression were significantly increased by exposure to both ammonia and proinflammatory mediators and although modest, these effects were additive suggestive of a synergistic mechanism. These findings suggest that worsening of brain edema and its complications in ALF due to proinflammatory mechanisms may result from exacerbation of oxidative stress-related mechanisms rather than upregulation of AQP-4 or decreases in expression of the astrocytic structural protein GFAP.

In the present study, the effects of minocycline on progression of encephalopathy and brain edema in rats with acute liver failure (ALF) resulting from hepatic devascularization were studied in relation to the antioxidant action of the drug. ALF rats were sacrificed at precoma and coma stages of encephalopathy along with their appropriate sham-operated controls. Minocycline-treated ALF rats were sacrificed in parallel with comatose vehicle-treated ALF controls. Microglial activation was assessed using CD11b/c (OX-42) immunohistochemistry. Nitrite/nitrate levels in plasma and brain were measured using the Griess reaction. Expression of nitric oxide synthase (NOS) isoforms and heme oxygenase-1 (HO-1) were measured using real-time quantitative PCR and Western blot analysis. Increased nitrite/nitrate levels were observed in the plasma of ALF rats at coma stage of encephalopathy compared to sham-operated controls. Increased expression of HO-1 mRNA and protein was observed in the frontal cortex of ALF rats at both precoma and coma stages of encephalopathy. Significant increases in expression of endothelial (eNOS) and inducible (iNOS) isoforms of NOS mRNA and protein occurred only at coma stages of encephalopathy accompanied by increased brain nitrite/nitrate concentrations. As expected, minocycline attenuated microglial activation as confirmed by decreased OX-42 immunoreactivity, normalized nitrite/nitrate levels in brain and significantly attenuated HO-1, eNOS and iNOS expression. These results indicate that the beneficial effect of minocycline on the neurological complications of ALF is mediated, at least in part, by reduction of oxidative/nitrosative stress.

It has been proposed that proinflammatory mechanisms are involved in the pathogenesis of brain edema in acute liver failure (ALF). The aim of this study was to assess the contribution of cerebral inflammation to the neurologic complications of ALF and to assess the antiinflammatory effect of mild hypothermia. Upregulation of CD11b/c immunoreactivity, consistent with microglial activation, was observed in the brains of ALF rats at coma stages of encephalopathy. Interleukin-1beta (IL-1beta), tumor necrosis factor-alpha (TNF-alpha), and interleukin-6 (IL-6) mRNAs were increased two to threefold in the brains of ALF rats compared with that in sham-operated controls. The magnitude of increased expression of proinflammatory cytokines in the brain was correlated with the progression of encephalopathy and the onset of brain edema. Significant increases in IL-1beta, IL-6, and TNF-alpha levels were also found in the sera and cerebrospinal fluid (CSF) of these animals. Mild hypothermia delayed the onset of encephalopathy, prevented brain edema, and concomitantly attenuated plasma, brain, and CSF proinflammatory cytokines. These results show that experimental ALF leads to increases in brain production of proinflammatory cytokines, and afford the first direct evidence that central inflammatory mechanisms play a role in the pathogenesis of the cerebral complications of ALF. Antiinflammatory agents could be beneficial in the management of these complications.

Lipocalin 2 (Lcn2), a mammalian protein that is expressed and secreted in various pathologic states, binds siderophores, which are high-affinity iron chelators. Besides its role in limiting iron availability to pathogens in the setting of bacterial infection, Lcn2:siderophore complexes can also deliver iron to cells. In this study, we examined Lcn2 regulation in the liver of mice in situations of increased iron utilization, namely, during anemia. Anemia induced by phlebotomy, iron deprivation, or phenylhydrazine treatment was associated with upregulation of Lcn2 gene expression in the liver and elevation of serum Lcn2 protein levels. We further explored the participation of several factors known to co-occur during anemia, including hypoxia, changes in iron levels, and erythropoietic drive, in the regulation of Lcn2 by anemia. We found that hypoxia, but not iron or erythropoietin, caused an induction of Lcn2 expression. The upregulation of Lcn2 levels by anemia and hypoxia, which is not directly mediated by iron or erythropoietin, suggests a possible physiological role for Lcn2 during increased iron utilization and mobilization from stores.

Summary Background Patients and clinicians share concerns that generic drug substitution might lead to loss of efficacy or emergence of adverse events. In this trial, we assessed US Food and Drug Administration (FDA) bioequivalence standards by studying the effects of switching between two disparate generic immediate-release lamotrigine products in patients with epilepsy. Methods The Equivalence among Generic Antiepileptic Drugs (EQUIGEN) chronic-dose study was a randomised, double-blind, crossover study that enrolled adults (aged ≥18 years) with epilepsy from six epilepsy centres at academic institutions across the USA who were receiving immediate-release lamotrigine dosed at 100 mg, 200 mg, 300 mg, or 400 mg twice daily. Eligible patients were randomly allocated (1:1) to one of two treatment sequences (sequence 1 or sequence 2), comprising four study periods of 14 days each. During each 14-day treatment period, patients received balanced doses of an oral generic lamotrigine product every 12 h (200–800 mg total, identical to lamotrigine dose prior to study enrolment); after each 14-day period, patients were crossed over to receive the other generic product. Computer-based randomisation was done using random permuted blocks of size two or four for each site to prevent sequence predictability. Both patients and study personnel were masked to the generic products selected, their predicted exposure (ie, "high" vs "low"), and their group allocation. The primary outcome of this trial was bioequivalence between the generic products, which was assessed at the end of the study through a comparison of maximum plasma concentration (C max ) and area under the concentration–time curve (AUC) for each product in the analysis population (all patients who completed all four treatment periods). Bioequivalence was established if the 90% CIs of the ratios of these two parameters for the two products were within equivalence limits (80–125%) in the analysis population. This study is registered with ClinicalTrials.gov\, number NCT01713777. Findings Between April 25, 2013, and Aug 12, 2014, 35 eligible patients were enrolled and randomly assigned to treatment sequence 1 (n=15) or treatment sequence 2 (n=20). 33 patients completed all four treatment periods and were included in the primary outcome analysis. The 90% CIs of the ratios of both C max and AUC were within equivalence limits (AUC 90% CI 98–103, C max 90% CI 99–105), showing that lamotrigine exposures were equivalent between the generic products. No significant changes in seizure frequency or adverse events were recorded. No deaths, study-related serious adverse events, or changes in clinical laboratory values or vital signs occurred during this study. Interpretation Disparate generic lamotrigine products in patients with epilepsy showed bioequivalence with no detectable difference in clinical effects, confirming that US Food and Drug Administration bioequivalence standards are appropriate. Funding American Epilepsy Society, Epilepsy Foundation, and US Food and Drug Administration.

OBJECTIVE To test the current U.S. Food and Drug Administration (FDA) bioequivalence standard in a comparison of generic and brand-name drug pharmacokinetic (PK) performance in "generic-brittle" patients with epilepsy under clinical use conditions. METHODS This randomized, double-blind, multiple-dose, steady-state, fully replicated bioequivalence study compared generic lamotrigine to brand-name Lamictal in "generic-brittle" patients with epilepsy (n = 34) who were already taking lamotrigine. Patients were repeatedly switched between masked Lamictal and generic lamotrigine. Intensive PK blood sampling at the end of each 2-week treatment period yielded two 12-h PK profiles for brand-name and generic forms for each patient. Steady-state area under the curve (AUC), peak plasma concentration (Cmax ), and minimum plasma concentration (Cmin ) data were subjected to conventional average bioequivalence (ABE) analysis, reference-scaled ABE analysis, and within-subject variability (WSV) comparisons. In addition, generic-versus-brand comparisons in individual patients were performed. Secondary clinical outcomes included seizure frequency and adverse events. RESULTS Generic demonstrated bioequivalence to brand. The 90% confidence intervals of the mean for steady-state AUC, Cmax , and Cmin for generic-versus-brand were 97.2-101.6%, 98.8-104.5%, and 93.4-101.0%, respectively. The WSV of generic and brand were also similar. Individual patient PK ratios for generic-versus-brand were similar but not identical, in part because brand-versus-brand profiles were not identical, even though subjects were rechallenged with the same product. Few subjects had seizure exacerbations or tolerability issues with product switching. One subject, however, reported 267 focal motor seizures, primarily on generic, although his brand and generic PK profiles were practically identical. SIGNIFICANCE Some neurologists question whether bioequivalence in healthy volunteers ensures therapeutic equivalence of brand and generic antiepileptic drugs in patients with epilepsy, who may be at increased risk for problems with brand-to-generic switching. Bioequivalence results in "generic-brittle" patients with epilepsy under clinical conditions support the soundness of the FDA bioequivalence standards. Adverse events on generic were not related to the small, allowable PK differences between generic and brand.

Hereditary hemochromatosis (HH), an iron overload disease associated with mutations in the HFE gene, is characterized by increased intestinal iron absorption and consequent deposition of excess iron, primarily in the liver. Patients with HH and Hfe-deficient (Hfe-/-) mice manifest inappropriate expression of the iron absorption regulator hepcidin, a peptide hormone produced by the liver in response to iron loading. In this study, we investigated the contribution of Hfe expression in macrophages to the regulation of liver hepcidin levels and iron loading. We used bone marrow transplantation to generate wild-type (wt) and Hfe-/- mice chimeric for macrophage Hfe gene expression. Reconstitution of Hfe-deficient mice with wt bone marrow resulted in augmented capacity of the spleen to store iron and in significantly decreased liver iron loading, accompanied by a significant increase of hepatic hepcidin mRNA levels. Conversely, wt mice reconstituted with Hfe-deficient bone marrow had a diminished capacity to store iron in the spleen but no significant alterations of liver iron stores or hepcidin mRNA levels. Our results suggest that macrophage Hfe participates in the regulation of splenic and liver iron concentrations and liver hepcidin expression. (Blood. 2005;106:2189-2195)

Background The effects of tacrolimus (FK506) and malononitrilamides (MNA) (FK778 and FK779) monotherapy and combination therapy were examined in prevention of acute heart and kidney allograft rejection and reversal of ongoing acute heart allograft rejection in the rat. Methods. Brown Norway (RT1 n )-to-Lewis (RT1 1 ) and ACI (RT1 a )-to-Lewis (RT1 1 ) combinations were used, respectively, for heart and kidney transplantation models. Immunosuppressants were administered orally from day 1 to day 14 for preventing acute rejection and from day 4 to day 34 after transplantation for the reversal of ongoing acute rejection. Results. In the prevention of acute heart rejection model, recipient rats treated with monotherapy of tacrolimus or MNA (FK778, FK779) showed a dose-related prolongation of mean survival time (MST) compared with naive control rats (P

BACKGROUND: Malononitrilamide 715 (FK778) is a new class of low-molecular-weight immunosuppressant that is a derivative of the active metabolite of leflunomide, A77 1726. In this study, the authors evaluated the combined effect of FK778 with tacrolimus in prevention of renal allograft rejection in Vervet monkeys. METHODS: Male Vervet monkeys were obtained from Caribbean Primates Ltd. Donor and recipient monkeys were from different breeding colonies. Eleven groups (n>or=4 per group) were involved in this study. FK778 and tacrolimus were administered orally for 60 days according to protocol. RESULTS: Naive controls rejected renal grafts, with a median survival time (MST) of 8.0 days in group 1. When recipient monkeys were treated with tacrolimus 1.0 mg/kg/day in group 2 or FK778 2.5 mg/kg/day in group 3, the MST was 16.0 days (P=0.001) and 11.0 days (P=0.266), respectively. Combination therapy of these two agents at the same doses immediately after transplantation resulted in an MST of 25.0 days (P=0.016) in group 4. When tacrolimus was initiated immediately after transplantation and FK778 treatment was delayed until day 7 after surgery in group 5, recipient survivals were significantly prolonged to 38.0 days (P=0.02). These results were repeatable when FK778 5.0 mg/kg/day (9.0 days, P=0.544 in group 6) was combined with tacrolimus 1.0 mg/kg/day immediately after transplantation (8.0 days, P=0.339) in group 7, or when FK778 was delayed 7 days (60.0 days, P=0.002) in group 8. Furthermore, it was also repeatable when FK778 10 mg/kg/day was combined with tacrolimus 1.0 mg/kg/day with a 7-day delay. CONCLUSIONS: A significant prolongation of renal allograft survival was produced when FK778 administration was delayed by 7 days combined with tacrolimus in Vervet monkeys.

The application of multiple immunosuppressive therapy for organ transplantation could enhance therapeutic efficacy, while minimizing the toxicity of individual drugs used in the regimen. In this study, the effect of the combined therapy of vincristine (VCR) with tacrolimus (FK506) or sirolimus (rapamycin, RAPA) was tested in prevention of acute heart allograft rejection in the rat. A Brown Norway (BN, RT 1(n)) to Lewis (LEW, RT 1(1)) rat combination was used in a heart allografting model. VCR was administered intraperitoneally once daily, while FK506 and RAPA were given by gavage once daily for 14 days after transplantation. There were dose-related prolongations of mean survival time (MST) to monotherapy of VCR, FK506, or RAPA. The MST in combination therapy indicated that a synergistic interaction was produced when compared with the respective monotherapies: VCR 0.05 mg/kg/day + FK506 0.5 mg/kg/day (16.00 +/- 1.79 days, P = 0.001; combination index (CI) = 0.557); VCR 0.05 mg/kg/day + FK506 1.0 mg/kg/day (29.00 +/- 10.54 days, P = 0.001; CI = 0.598); VCR 0.05 mg/kg/day + RAPA 0.2 mg/kg/day (17.33 +/- 1.97 days, P = 0.001; CI = 0.500); and VCR 0.05 mg/kg/day + RAPA 0.4 mg/kg/day (21.17 +/- 3.19 days, P = 0.001; CI = 0.838). Combination therapy of VCR and FK506 or RAPA produced synergistic effects in prevention of acute heart allograft rejection in the rat.

Narrow therapeutic index (NTI) drugs are those drugs where small differences in dose or blood concentration may lead to serious therapeutic failures and/or adverse drug reactions that are life-threatening or result in persistent or significant disability or incapacity. This chapter describes various public perspectives on the interchangeability of NTI drugs, discusses the characteristics of NTI drugs, provides an overview of regulatory definitions and bioequivalence approaches taken by major regulatory bodies on NTI drugs, as well as presents case studies to illustrate an example process of classifying drugs with NTI. The FDA’s approach recommends a four-way, fully replicated, crossover design in healthy subjects or patients to permit simultaneous equivalence comparison of the mean and within-subject variability of the test and reference drug products, which offers greater assurance of therapeutic equivalence of NTI drug products. The challenges and future opportunities regarding NTI drugs are also discussed.

Glioblastoma is the most lethal form of brain tumors and one of the most fatal human cancers with universal recurrence post-surgical procedures and common failure in the salvage therapies. Fluorescence agents introduced to facilitate the identification of cancerous tissues in surgical resection are facing challenges such as low sensitivity and specificity and ineffective delivery to intracerebral tumor via systemic administration. Recently, we have developed a porphyrin-lipid assembled HDL-like nanovesicle (porphyHDL) with sub 20 nm in size. The highly packed porphyrin molecules in the assembly allows for the intrinsically labeling with Cu-64 and provides fluorescence emission and great PDT potency upon laser irradiation, thus making this nanocomplex a multifunctional reagent suitable for pre- and intra-operative imaging and surgical bed clean-up.

Narrow therapeutic index drugs are defined as those drugs where small differences in dose or blood concentration may lead to serious therapeutic failures and/or adverse drug reactions that are life-threatening or result in persistent or significant disability or incapacity. The US Food and Drug Administration proposes that the bioequivalence of narrow therapeutic index drugs be determined using a scaling approach with a four-way, fully replicated, crossover design study in healthy subjects that permits the simultaneous equivalence comparison of the mean and within-subject variability of the test and reference products. The proposed bioequivalence limits for narrow therapeutic index drugs of 90.00%-111.11% would be scaled based on the within-subject variability of the reference product. The proposed study design and data analysis should provide greater assurance of therapeutic equivalence of narrow therapeutic index drug products.

Chronic liver failure leads to hyperammonemia, a central component in the pathogenesis of hepatic encephalopathy (HE); however, a correlation between blood ammonia levels and HE severity remains controversial. It is believed oxidative stress plays a role in modulating the effects of hyperammonemia. This study aimed to determine the relationship between chronic hyperammonemia, oxidative stress, and brain edema (BE) in two rat models of HE: portacaval anastomosis (PCA) and bile-duct ligation (BDL). Ammonia and reactive oxygen species (ROS) levels, BE, oxidant and antioxidant enzyme activities, as well as lipid peroxidation were assessed both systemically and centrally in these two different animal models. Then, the effects of allopurinol (xanthine oxidase inhibitor, 100 mg/kg for 10 days) on ROS and BE and the temporal resolution of ammonia, ROS, and BE were evaluated only in BDL rats. Similar arterial and cerebrospinal fluid ammonia levels were found in PCA and BDL rats, both significantly higher compared to their respective sham-operated controls (p < 0.05). BE was detected in BDL rats (p < 0.05) but not in PCA rats. Evidence of oxidative stress was found systemically but not centrally in BDL rats: increased levels of ROS, increased activity of xanthine oxidase (oxidant enzyme), enhanced oxidative modifications on lipids, as well as decreased antioxidant defense. In PCA rats, a preserved oxidant/antioxidant balance was demonstrated. Treatment with allopurinol in BDL rats attenuated both ROS and BE, suggesting systemic oxidative stress is implicated in the pathogenesis of BE. Analysis of ROS and ammonia temporal resolution in the plasma of BDL rats suggests systemic oxidative stress might be an important “first hit”, which, followed by increases in ammonia, leads to BE in chronic liver failure. In conclusion, chronic hyperammonemia and oxidative stress in combination lead to the onset of BE in rats with chronic liver failure.

Acute liver failure (ALF) is characterized neuropathologically by cytotoxic brain edema and biochemically by increased brain ammonia and its detoxification product, glutamine. The osmotic actions of increased glutamine synthesis in astrocytes are considered to be causally related to brain edema and its complications (intracranial hypertension, brain herniation) in ALF. However studies using multinuclear (1)H- and (13)C-NMR spectroscopy demonstrate that neither brain glutamine concentrations per se nor brain glutamine synthesis rates correlate with encephalopathy grade or the presence of brain edema in ALF. An alternative mechanism is now proposed whereby the newly synthesized glutamine is trapped within the astrocyte as a consequence of down-regulation of its high affinity glutamine transporter SNAT5 in ALF. Restricted transfer out of the cell rather than increased synthesis within the cell could potentially explain the cell swelling/brain edema in ALF. Moreover, the restricted transfer of glutamine from the astrocyte to the adjacent glutamatergic nerve terminal (where glutamine serves as immediate precursor for the releasable/transmitter pool of glutamate) could result in decreased excitatory transmission and excessive neuroinhibition that is characteristic of encephalopathy in ALF. Paradoxically, in spite of renewed interest in arterial ammonia as a predictor of raised intracranial pressure and brain herniation in ALF, ammonia-lowering agents aimed at reduction of ammonia production in the gut have so far been shown to be of limited value in the prevention of these cerebral consequences. Mild hypothermia, shown to prevent brain edema and intracranial hypertension in both experimental and human ALF, does so independent of effects on brain glutamine synthesis; whether or not hypothermia restores expression levels of SNAT5 in ALF awaits further studies. While inhibitors of brain glutamine synthesis such as methionine sulfoximine, have been proposed for the prevention of brain edema in ALF, potential adverse effects have so far limited their applicability.

Ammonia is neurotoxic and believed to play a major role in the pathogenesis of hepatic encephalopathy (HE). It has been demonstrated, in vitro and in vivo, that acute and high ammonia treatment induces oxidative stress. Reactive oxygen species (ROS) are highly reactive and can lead to oxidization of proteins resulting in protein damage. The present study was aimed to assess oxidative status of proteins in plasma and brain (frontal cortex) of rats with 4-week portacaval anastomosis (PCA). Markers of oxidative stress, 4-hydroxy-2-nonenal (HNE) and carbonylation were evaluated by immunoblotting in plasma and frontal cortex. Western blot analysis did not demonstrate a significant difference in either HNE-linked or carbonyl derivatives on proteins between PCA and sham-operated control rats in both plasma and frontal cortex. The present study suggests PCA-induced hyperammonemia does not lead to systemic or central oxidative stress.

Encephalopathy and brain edema are serious complications of acute liver failure (ALF). The precise pathophysiologic mechanisms responsible have not been fully elucidated but it has been recently proposed that microglia-derived proinflammatory cytokines are involved. In the present study we evaluated the role of microglial activation and the protective effect of the anti-inflammatory drug minocycline in the pathogenesis of hepatic encephalopathy and brain edema in rats with ALF resulting from hepatic devascularisation. ALF rats were killed 6 h after hepatic artery ligation before the onset of neurological symptoms and at coma stages of encephalopathy along with their appropriate sham-operated controls and in parallel with minocycline-treated ALF rats. Increased OX-42 and OX-6 immunoreactivities confirming microglial activation were accompanied by increased expression of interleukins (IL-1beta, IL-6) and tumor necrosis factor-alpha (TNF-alpha) in the frontal cortex at coma stage of encephalopathy in ALF rats compared with sham-operated controls. Minocycline treatment prevented both microglial activation as well as the up-regulation of IL-1beta, IotaL-6 and TNF-alpha mRNA and protein expression with a concomitant attenuation of the progression of encephalopathy and brain edema. These results offer the first direct evidence for central proinflammatory mechanisms in the pathogenesis of brain edema and its complications in ALF and suggest that anti-inflammatory agents may be beneficial in these patients.

Encephalopathy and brain edema are serious complications of acute liver failure (ALF). The precise pathophysiologic mechanisms responsible have not been fully elucidated but it has been suggested that oxidative/nitrosative stress is involved. In the present study we evaluated the role of oxidative/nitrosative stress in the pathogenesis of hepatic encephalopathy and brain edema in rats with ALF resulting from hepatic devascularization. We also studied the effect of hypothermia, a treatment previously shown to delay the progression of encephalopathy and the onset of brain edema, on ALF-induced oxidative stress. ALF rats were sacrificed at precoma and coma stages of encephalopathy along with their appropriate sham-operated controls. Hypothermic ALF rats were sacrificed in parallel with normothermic comatose ALF rats. Nitric oxide production in plasma and brain was assessed indirectly by measuring the level of its stable end products, nitrite/nitrate (NOx), using the Griess reagent. Expression of nitric oxide synthase (NOS) isoforms and heme oxygenase-1 (HO-1) were measured using real-time quantitative PCR, Western blot analysis and immunohistochemistry. Increased nitrite/nitrate levels were observed in the plasma and frontal cortex in ALF rats at coma stage of encephalopathy compared to sham-operated controls. Increased expression of HO-1 protein and mRNA was observed in the frontal cortex of ALF rats at both precoma and coma stages of encephalopathy. Significant increases in expression of endothelial and inducible NOS mRNA isoforms also occurred at precoma and coma stages of encephalopathy. Expression of the neuronal nitric oxide synthase isoform (nNOS) was not altered by ALF. Hypothermia normalized nitrite/nitrate levels in brain and significantly attenuated HO-1, eNOS and iNOS expression. These results suggest that, oxidative/nitrosative stress participates in the pathogenesis of brain edema and its complications in ALF and that the beneficial effect of hypothermia depends in part on its ability to inhibit oxidative/nitrosative stress-related mechanisms.

Hepcidin is a negative regulator of iron absorption produced mainly by the liver in response to changes in iron stores and inflammation, and its levels have been shown to regulate the intestinal basolateral iron transporter ferroportin1 ( Fp1). Hereditary hemochromatosis patients and Hfe-deficient mice show inappropriate expression of hepcidin but, in apparent contradiction, still retain the ability to regulate iron absorption in response to alterations of iron metabolism. To further understand the molecular relationships among Hfe, hepcidin, and Fp1, we investigated hepcidin and Fp1 regulation in Hfe-deficient mice ( Hfe−/−and β2m−/−) in response to iron deprivation, iron loading, and acute inflammation. We found that whereas basal hepcidin levels were manifestly dependent on the presence of Hfe and on the mouse background, all Hfe-deficient mice were still able to regulate hepcidin in situations of altered iron homeostasis. In the liver, Fp1 was modulated in opposite directions by iron and LPS, and its regulation in Hfe-deficient mice was similar to that observed in wild-type mice. In addition, we found that iron-deprived mice were able to mount a robust response after LPS challenge and that Toll-like receptor 4 (TLR-4)-deficient mice fail to regulate hepcidin expression in response to LPS. In conclusion, these results suggest that although Hfe is necessary for the establishment of hepcidin basal levels, it is dispensable for hepcidin regulation through both the iron-sensing and inflammatory pathways, and hepatic Fp1 regulation is largely independent of hepcidin and Hfe. The inflammatory pathway overrides the iron-sensing pathway and is TLR-4 dependent.

Improved microsurgical techniques for en bloc vascularized adnexal isograft in the rat is described. The graft of the right ovary together with its fallopian tube and upper third of uterus was transplanted orthotopically with end-to-side anastomoses between the donor aortic segment and recipient aorta and between the donor vena cava segment and recipient inferior vena cava, with end-to-end anastomosis of the donor and recipient uterus in a syngeneic, bilaterally oophorectomized rat. All transplantations were successful in terms of immediate vascular patency rate (10/10, 100%). Evidence of resumed ovarian function was obtained in 9 out of 10 rats (9/10, 90.0%) by histological demonstration of the vaginal smear, in which pregnancies were achieved in six rats (6/10, 60.0%) and six litters of healthy offspring were delivered 9 weeks later after transplantation. These results suggest that microsurgical ovarian transplantation provide a new and potential experimental model for the study of fertility restoration in humans. © 2002 Wiley-Liss, Inc. MICROSURGERY 22:30–33 2002 DOI 10.1002/micr.22006