Steven S. Rossi

Ursodeoxycholic acid in the treatment of primary biliary cirrhosis

BACKGROUND/AIMS A double-blind, placebo-controlled trial of ursodeoxycholic acid (UDCA) was conducted in 180 patients with primary biliary cirrhosis (PBC) to define the efficacy and safety of UDCA. Efficacy was assessed by time to treatment failure defined as death; liver transplantation; histological progression; development of varices, ascites, or encephalopathy; doubling of total serum bilirubin levels; progression of fatigue or pruritus; drug toxicity; or voluntary withdrawal. METHODS Patients with well-defined PBC underwent complete history, physical examination, liver chemistries, ultrasonography, upper endoscopy, and liver biopsy at entry as well as at 2 years. Liver chemistries were determined every 3 months. RESULTS In patients receiving UDCA, treatment failure was delayed compared with the placebo-treated group (P = 0.0003, log rank test). Seven patients receiving UDCA died or required transplantation compared with 12 in the placebo group (P = 0.18). No patients discontinued UDCA because of side effects of toxicity. CONCLUSIONS UDCA was extraordinarily safe and well tolerated, and its use was associated with delayed progression of the disease as defined in this study. However, the lack of effects on symptoms, histology, and the need for liver transplantation or survival indicate that further evaluation is necessary to determine the ultimate role of UDCA in the treatment of PBC.

Transmission of endoplasmic reticulum stress and pro-inflammation from tumor cells to myeloid cells

Metabolic, infectious, and tumor cell-intrinsic noxae can all evoke the endoplasmic reticulum (ER) stress response in tumor cells, which is critical for tumor cell growth and cancer progression. Evidence exists that the ER stress response can drive a proinflammatory program in tumor cells and macrophages but, to our knowledge, a role for the tumor ER stress response in influencing macrophages and inflammation in the tumor microenvironment has not been suggested. Here we show that macrophages cultured in conditioned medium from ER-stressed tumor cells become activated, and themselves undergo ER stress with the up-regulation of Grp78, Gadd34, Chop, and Xbp-1 splicing, suggesting a general activation of the ER stress-signaling pathways. Furthermore, these macrophages recapitulate, amplify and expand the proinflammatory response of tumor cells. We term this phenomenon “transmissible” ER stress. Although neither Toll-like receptor (TLR)2 nor interleukin 6 receptor (IL6R) signaling is involved, a reduction was observed in the transmission of ER stress to TLR4 KO macrophages, consistent with the fact that a second signal through TLR4 combined with exposure to tumor ER stress-conditioned medium results in a faster ER stress response and an enhancement of proinflammatory cytokine production in macrophages. The injection of tumor ER stress-conditioned medium into WT mice elicited a generalized ER stress response in the liver. We suggest that transmissible ER stress is a mechanism through which tumor cells can control myeloid cells by directing them toward a proinflammatory phenotype, thus facilitating tumor progression.

Chronically Infused Intrathecal Morphine in Dogs

Background Despite the extensive use of intrathecal morphine infusion for pain, no systematic safety studies exist on its effects in high concentrations. The authors assessed the effects of morphine and clonidine given 28 days intrathecally in dogs. Methods Beagles with lumbar intrathecal catheters received solutions delivered by a vest-mounted infusion pump. Six groups (n = 3 each) received infusions (40 &mgr;l/h) of saline or 1.5, 3, 6, 9, or 12 mg/day of morphine for 28 days. Additional groups received morphine at 40 &mgr;l/h (1.5 mg/day) plus clonidine (0.25–1.0 mg/day) or clonidine alone at 100 &mgr;g/h (4.8 mg/day). Results In animals receiving 9 or 12 mg/day morphine, allodynia was observed shortly after initiation of infusion. A concentration-dependent increase in hind limb dysfunction evolved over the infusion interval. Necropsy revealed minimal reactions in saline animals. At the higher morphine concentrations (all dogs receiving 12 mg/day), there was a local inflammatory mass at the catheter tip that produced significant local tissue compression. All animals with motor dysfunction displayed masses, although all animals with masses did not show motor dysfunction. The mass, arising from the dura-arachnoid layer, consisted of multifocal accumulations of neutrophils, monocytes, macrophages, and plasma cells. Inflammatory cells and endothelial cells displayed significant IL1&bgr;, TNF&agr;, iNOS, and eNOS immunoreactivity. No evidence of bacterial or fungal involvement was detected. There were no other changes in spinal morphologic characteristics. In four other groups of dogs, clonidine alone had no effect and in combination with morphine reduced the morphine reaction. Conclusions The authors found that high intrathecal morphine concentrations lead to aseptic intrathecal inflammatory masses. The lack of effect of clonidine and the possible suppressive effects of clonidine on the local reaction suggest the utility of such coadministration.

Giardia lamblia: The roles of bile, lactic acid, and pH in the completion of the life cycle in vitro

Large numbers (10(4) to greater than 10(5)/ml) of Type I water-resistant Giardia lamblia cysts were produced in vitro under conditions that are characteristic of the human intestinal lumen. We define Type I cyst morphology as oval shaped, smooth, and refractile, with cyst wall, axostyle, and median body visible in relief by Normarski differential interference contrast optics. Human and porcine bile induced higher levels of encystation than bovine bile at the alkaline pH (7.8) which occurs in the human lower small intestine. High-pressure liquid chromatography analysis showed that the porcine bile had a preponderance of hyocholate, rather than cholate, while bovine bile had less chenodeoxycholate and more deoxycholate than human bile. Lactic acid, a major product of bacterial metabolism in the human colon, further stimulated encystation. Growth of the preencystation culture without bile also increased subsequent encystation. More than 90% of Type I cysts produced with porcine bile plus lactic acid were viable as indicated by the uptake and retention of fluorescein diacetate and exclusion of propidium iodide. Biological activity of in vitro-derived water-resistant cysts was demonstrated by the observation that 1 to 9.5% excysted in vitro. The percentage of excystation was greatly decreased following encystation at pH 7.0 or by omission of bile or lactic acid. This is the first quantitative in vitro demonstration of the complete life cycle of G. lamblia from humans.

The combination of ursodeoxycholic acid and methotrexate for patients with primary biliary cirrhosis: The results of a pilot study

Ursodeoxycholic acid (UDCA) and methotrexate (MTX) have both been proposed as treatments for patients with primary biliary cirrhosis (PBC). It has been suggested that a combination of the two drugs may offer advantages over either used separately. In this pilot study, we sought to evaluate the safety and efficacy of this combination for patients with PBC. Thirty-two patients with antimitochondrial antibody positive PBC were prospectively entered into a pilot study and received UDCA, 13 to 15 mg/kg/d, in conjunction with MTX, 0.25 mg/kg/wk, for a period of 2 years. The results of this treatment were compared with those obtained from 180 patients with PBC studied in a placebo-controlled trial of UDCA alone conducted during the same period. Patients in the pilot study and randomized study were comparable with regard to age, gender, and liver biochemistries. The UDCA/MTX-treated patients were of earlier histologic stage and had a lower mean Mayo risk score. During this period, seven patients in the UDCA/MTX group were withdrawn, four for pulmonary toxicity (two who required hospitalization), and one each with mouth ulcer, extreme fatigue, and hair loss. The use of UDCA/MTX was not associated with improvement in symptoms. In the patients receiving UDCA/MTX, biochemical changes were comparable to those of patients receiving UDCA alone but superior to those in the placebo group (P < .05). Histological changes were comparable in all groups at 2 years. Cessation of MTX while UDCA was continued led to no deterioration in liver biochemistries.(ABSTRACT TRUNCATED AT 250 WORDS)

Characterisation of patients with a complete biochemical response to ursodeoxycholic acid.

Ursodeoxycholic acid (UDCA) leads to biochemical and clinical improvement in many patients with primary biliary cirrhosis (PBC); although, the response is variable. This study compared UDCA treated patients with complete normalisation of biochemical functions to those without such improvement. Of the 65 patients receiving UDCA, 12 (19%) showed normalisation of liver biochemical functions at two years. The remaining 53 patients showed a less complete response. Mean (SD) alkaline phosphatase and total serum bilirubin values were significantly lower at entry in the patients whose liver biochemistry tests normalised (912 (732) U/l v 1417 (1021) U/l, p = 0.003, and 0.7 (12.1 (5.2) mumol/l v 38.9 (48.5) mumol/l, p = 0.0002, respectively), and percentage of UDCA in biliary bile acid was higher (56.3 (9.5)% v 38.3 (21.1)%, p = 0.03). Patients with biochemically and histologically less severe disease, and greater enrichment of biliary bile with UDCA, are more likely to respond favourably to the drug. The main objective of continued study will be to find out if normal liver biochemical functions can retard disease progression. The association of greater UDCA enrichment with complete biochemical responses suggests that higher doses of UDCA should be evaluated.

Efavirenz concentrations in CSF exceed IC50 for wild-type HIV

OBJECTIVES HIV-associated neurocognitive disorders remain common despite use of potent antiretroviral therapy (ART). Ongoing viral replication due to poor distribution of antivirals into the CNS may increase risk for HIV-associated neurocognitive disorders. This studys objective was to determine penetration of a commonly prescribed antiretroviral drug, efavirenz, into CSF. METHODS CHARTER is an ongoing, North American, multicentre, observational study to determine the effects of ART on HIV-associated neurological disease. Single random plasma and CSF samples were drawn within 1 h of each other from subjects taking efavirenz between September 2003 and July 2007. Samples were assayed by HPLC or HPLC/mass spectrometry with detection limits of 39 ng/mL (plasma) and <0.1 ng/mL (CSF). RESULTS Eighty participants (age 44 ± 8 years; 79 ± 15 kg; 20 females) had samples drawn 12.5 ± 5.4 h post-dose. The median efavirenz concentrations after a median of 7 months [interquartile range (IQR) 2-17] of therapy were 2145 ng/mL in plasma (IQR 1384-4423) and 13.9 ng/mL in CSF (IQR 4.1-21.2). The CSF/plasma concentration ratio from paired samples drawn within 1 h of each other was 0.005 (IQR 0.0026-0.0076; n = 69). The CSF/IC(50) ratio was 26 (IQR 8-41) using the published IC(50) for wild-type HIV (0.51 ng/mL). Two CSF samples had concentrations below the efavirenz IC(50) for wild-type HIV. CONCLUSIONS Efavirenz concentrations in the CSF are only 0.5% of plasma concentrations but exceed the wild-type IC(50) in nearly all individuals. Since CSF drug concentrations reflect those in brain interstitial fluids, efavirenz reaches therapeutic concentrations in brain tissue.

Time Course and Role of Morphine Dose and Concentration in Intrathecal Granuloma Formation in Dogs A Combined Magnetic Resonance Imaging and Histopathology Investigation

Background:Intrathecal morphine infusion leads to intrathecal granulomas. In dogs, the authors examined time course of granuloma formation and the role of concentration in granuloma development. Methods:Dogs were prepared with lumbar intrathecal catheters and vest-mounted pumps. To define the time course of granuloma formation, serial magnetic resonance imaging was performed in animals receiving 10 or 31 days of morphine infusion (12.5 mg/ml at 40 &mgr;l/h). At these times, morphine was removed from the infusate, and further magnetic resonance images were acquired over 14–35 additional days. To assess dose versus concentration, dogs received 28-day infusions of vehicle, 12 mg morphine/day as 12.5 mg/ml at 40 &mgr;l/h, or 1.5 mg/ml at 334 &mgr;l/h (12 mg/day) for 28 days. Additional dogs received 3 mg/day as 12.5 mg/ml at 10 &mgr;l/h. Results:Serial magnetic resonance images in dogs receiving morphine (12.5 mg/ml at 40 &mgr;l/h) revealed pericatheter-enhancing tissues as early as 3 days with a prominent signal by 10 days. Removal of morphine reduced the mass volume within 7 days. At a fixed infusion rate, the incidence of granuloma formation with the continuous intrathecal infusion of morphine ranged from 0 in vehicle-treated dogs to 100% in dogs treated with 12.5 mg/ml at 40 &mgr;l/h (12 mg/day). Infusion of 12 mg/day at 1.5 mg/ml (334 &mgr;l/h) resulted in granuloma in one of four animals. The authors found that infusion of morphine in different concentrations at a fixed rate resulted in a dose-dependent increase in concentration, with the granuloma-producing, dose-yielding lumbar cerebrospinal fluid morphine concentrations around 40 &mgr;g/ml. Conclusions:Serial magnetic resonance imaging showed a rapid formation and regression of the masses initiated by intrathecal morphine infusion. These masses are dependent on local concentration.

Lopinavir tablet pharmacokinetics with an increased dose during pregnancy.

Objective:Reduced lopinavir concentrations have been demonstrated with use of the capsule formulation during the third trimester of pregnancy. This study determined lopinavir exposure with an increased dose of the new tablet formulation during the third trimester. Design:International Maternal Pediatric Adolescent AIDS Clinical Trials 1026s is a prospective nonblinded pharmacokinetic study in HIV-infected pregnant women, including a cohort receiving 2 lopinavir/ritonavir tablets (400 mg/100 mg) twice daily during the second trimester, 3 tablets (600 mg/150 mg) twice daily during the third trimester, and 2 tablets (400 mg/100 mg) twice daily postdelivery through 2 weeks postpartum. Methods:Steady-state 12-hour pharmacokinetic profiles were performed during pregnancy and at 2 weeks postpartum. Lopinavir and ritonavir were measured by reverse-phase high-performance liquid chromatography (detection limit, 0.09 mcg/mL). Results:Thirty-three women were studied. Median lopinavir AUC for the second trimester (n = 11), third trimester (n = 33), and postpartum (n = 27) were 72, 96, and 133 mcg·hr/mL, respectively. Median minimum lopinavir concentrations were 3.4, 4.9, and 6.9 mcg/mL. Conclusions:The higher lopinavir/ritonavir tablet dose (600 mg/150 mg) provided exposure during the third trimester similar to the average AUC (98 mcg·hr·mL−1) in nonpregnant adults taking 400 mg/100 mg twice daily. The higher dose should be used during the second and third trimesters of pregnancy. Postpartum dosing can be reduced to standard dosing before 2 weeks postpartum.

Atazanavir Pharmacokinetics With and Without Tenofovir during Pregnancy

Background:Few data are available describing atazanavir exposure during pregnancy, especially when used in combination with tenofovir, whose coadministration with atazanavir results in decreased atazanavir exposure. Design:International Maternal Pediatric Adolescent AIDS Clinical Trials 1026s is an ongoing, prospective, nonblinded study of antiretroviral pharmacokinetics in HIV-infected pregnant women that included 2 cohorts receiving atazanavir/ritonavir 300 mg/100 mg once daily, either with or without tenofovir. Methods:Intensive steady-state 24-hour pharmacokinetic profiles were performed during the third trimester and at 6-12 weeks postpartum. Atazanavir was measured by reverse-phase high-performance liquid chromatography (detection limit 0.047 mcg/mL). Pharmacokinetic targets were the estimated 10th percentile atazanavir area under the concentration versus time curve [(AUC): 29.4 mcg·hr·mL−1] in nonpregnant historical controls (mean AUC = 57 mcg·hr·mL−1) and a trough concentration of 0.15 mcg/mL, the concentration target used in therapeutic drug monitoring programs. Results:Median atazanavir AUC was reduced during the third trimester compared with postpartum for subjects not receiving tenofovir (41.9 vs. 57.9 mcg·hr·mL−1, P = 0.02) and for subjects receiving tenofovir (28.8 vs. 39.6 mcg·hr·mL−1, P = 0.04). During the third trimester, AUC was below the target in 33% (6 of 18) of women not receiving tenofovir and 55% (11 of 20) of women receiving tenofovir. Trough concentration was below the target in 6% (1 of 18) of women not receiving tenofovir and 15% (3 of 20) of women receiving tenofovir. The median (range) ratio of cord blood/maternal atazanavir concentration in 29-paired samples was 0.18 (0-0.45). Conclusions:Atazanavir exposure is reduced by pregnancy and by concomitant tenofovir use. A dose increase of atazanavir/ritonavir to 400 mg/100 mg may be necessary in pregnant women to ensure atazanavir exposure equivalent to that seen in nonpregnant adults.