Effect of adalimumab on joint disease: features of patients with psoriatic arthritis detected by magnetic resonance imaging.

BACKGROUND: Bone marrow oedema (BMO), synovitis, effusion and joint erosion on magnetic resonance imaging (MRI) may be used as outcome measures in psoriatic arthritis (PsA). OBJECTIVE: To assess the impact of adalimumab on BMO, synovitis, effusion and erosions in PsA, as measured by MRI. METHODS: Fifteen patients with active PsA (> or =3 tender and > or =3 swollen joints) were enrolled in an open-label pilot study. Each received adalimumab subcutaneously every other week for 24 weeks. MRI was obtained at baseline and 24 weeks. RESULTS: MRI was available for 11 patients, pre and post-therapy. BMO and effusion scores improved markedly after 24 weeks of adalimumab, while no significant change was noted in erosion score. An unanticipated finding, however, was the lack of improvement in the MRI synovitis score. CONCLUSIONS: Improvement in BMO and unchanged erosion scores may explain the "anti-erosive" effects of adalimumab in PsA. Persistence of BMO and synovitis on MRI suggests ongoing disease activity and supports the continuation of long-term anti-TNF therapy.

Adalimumab effectiveness for the treatment of ankylosing spondylitis is maintained for up to 2 years: long-term results from the ATLAS trial.

OBJECTIVE: To determine the long-term effect of adalimumab on patients with ankylosing spondylitis (AS) who participated in the Adalimumab Trial Evaluating Long-Term Efficacy and Safety in AS (ATLAS), a randomised, double-blind, placebo controlled, 24-week trial. METHODS: Patients received adalimumab 40 mg every other week (eow) or placebo for 24 weeks in ATLAS. At week 24, patients were switched to open-label adalimumab 40 mg eow. Efficacy measures included 20% improvement in the Assessment in SpondyloArthritis International Society (ASAS) criteria (ASAS20), ASAS40 and ASAS partial remission responses and changes in individual components of the ASAS20 response evaluations, for example, Bath AS Functional Index (BASFI) and Bath AS Disease Activity Index (BASDAI). Two-year interim data were analysed based on the total duration of adalimumab exposure, irrespective of the treatment randomisation group. RESULTS: At 2 years, 255 (82.0%) of the original 311 ATLAS patients continued receiving adalimumab treatment. Improvements in ASAS responses observed in ATLAS were sustained during long-term treatment; 64.5% (200/310) were ASAS20 responders, 50.6% (157/310) were ASAS40 responders and 33.5% (104/310) had maintained ASAS-defined partial remission. Changes in individual ASAS response components were sustained or improved during long-term adalimumab treatment. From ATLAS baseline to 2 years of adalimumab exposure, respectively, BASDAI improved from 6.3 (SD 1.7) to 2.4 (SD 2.3) and BASFI improved from 5.2 (SD 2.4) to 2.9 (SD 2.5). Adalimumab was well tolerated. No cases of tuberculosis, congestive heart failure, lupus-like symptoms, or demyelinating disease were reported. CONCLUSIONS: Adalimumab reduced the signs and symptoms of AS and induced partial remission for up to 2 years. The long-term safety profile was similar to the short-term safety profile. Trial registration information: NCT00085644.

Adalimumab for long-term treatment of psoriatic arthritis: 2-year data from the Adalimumab Effectiveness in Psoriatic Arthritis Trial (ADEPT).

OBJECTIVE: To evaluate the long-term effectiveness and tolerability of adalimumab in the treatment of psoriatic arthritis (PsA). METHODS: Patients with PsA who completed a 24-week, double-blind study of adalimumab versus placebo were eligible to enroll in an open-label extension study and receive adalimumab 40 mg subcutaneously every other week for up to an additional 120 weeks. At the time of this analysis, available efficacy evaluations throughout 2 years of treatment (n = 245) included American College of Rheumatology (ACR) 20%, 50% and 70% improvement scores, measures of joint disease and skin disease, disability and quality of life; modified total Sharp scores (mTSS) were available for 2.75 years of treatment for patients who received adalimumab in the 24-week study. RESULTS: After 24 weeks of double-blind treatment, the mean change in mTSS was -0.2 for the adalimumab group (N = 144) and 1.0 for the placebo group (N = 152; p<0.001), and outcomes for all individual ACR component variables were significantly improved in adalimumab compared with placebo-treated patients. Compared with 24-week responses, inhibition of radiographic progression and improvements in joint disease were maintained in most patients during long-term, open-label adalimumab treatment. Also, improvements in skin disease were maintained, with >20% of patients achieving the strict criterion of psoriasis area and severity index 100. The nature and frequency of adverse events during long-term adalimumab treatment were consistent with the safety profile during short-term treatment. CONCLUSIONS: The clinical and radiographic efficacy of adalimumab demonstrated during short-term treatment was sustained during long-term treatment. Adalimumab has a favourable risk-benefit profile in patients with PsA. TRIAL REGISTRATION NUMBER: NCT00195689.

Development and validation of the Spondyloarthritis Research Consortium of Canada (SPARCC) Enthesitis Index.

BACKGROUND: Enthesitis is a recommended core domain for assessment of ankylosing spondylitis (AS), but no measurement has yet been validated according to Outcome Measures in Rheumatoid Arthritis Clinical Trials (OMERACT) criteria. OBJECTIVE: The purpose of this study was to seek to validate an enthesitis index for patients with AS according to OMERACT criteria. METHODS: An enthesitis index was validated in two AS patient cohorts: (1) a longitudinal cohort (n = 223) and (2) 22 patients from three Canadian sites participating in a 24-week randomised placebo-controlled trial of adalimumab in AS. Construct validity was evaluated by correlation analysis with the Bath AS Disease Activity Index (BASDAI), the Bath AS Functional Index (BASFI) and quality of life instruments. Reproducibility was assessed by intraclass correlation coefficient (ICC), and responsiveness was assessed by Guyatt's effect size and standardised response mean. RESULTS: The most frequently affected sites were the greater trochanter and supraspinatus insertion ( approximately 20%). Patients with enthesitis had significantly greater scores for the BASDAI, BASFI, patient global, AS-specific quality of life index (ASQOL) and the Short Form 36 (SF-36) General Health Survey (p<0.001). The enthesitis score contributed significantly to variance in the BASDAI and BASFI. Interobserver ICCs were 0.96 in the longitudinal cohort and 0.89 and 0.77 in the adalimumab clinical trial cohort (for status and change score, respectively). Significant differences in change scores were evident for all patients after 24 weeks of adalimumab treatment, (p = 0.04), this being more significant when a subset of the most commonly affected entheses were analysed (p = 0.01). CONCLUSION: AS patients with enthesitis constitute a more severe subset of disease, and the Spondyloarthritis Research Consortium of Canada (SPARCC) Enthesitis Index is feasible and reliable for measurement of this condition. Discrimination requires further study in larger trials.

Adalimumab effectively reduces the signs and symptoms of active ankylosing spondylitis in patients with total spinal ankylosis.

OBJECTIVE: To evaluate the long-term safety and efficacy of adalimumab in patients with ankylosing spondylitis (AS) and total spinal ankylosis (TSA). DESIGN: Patients (n = 315) with active AS were randomised in a 2:1 ratio to receive adalimumab 40 mg every other week or placebo for 24 weeks followed by open-label adalimumab for up to 5 years. Two-year efficacy and safety data for 11 patients with investigator-defined TSA were evaluated. The primary end point was the ASsessment in AS International Working Group criteria for 20% improvement (ASAS20) at Week 12. On or after Week 12, ASAS20 non-responders could switch to open-label adalimumab. Other efficacy measurements included ASAS40, ASAS 5/6, ASAS partial remission, and 50% improvement in the Bath AS Disease Activity Index (BASDAI 50). RESULTS: 6 of 11 TSA patients were randomised to adalimumab and 5 to placebo. At Week 12, 50% of the adalimumab-treated patients achieved an ASAS20 response and 33% achieved an ASAS40, ASAS 5/6 and BASDAI 50. No placebo-treated patients achieved any response criteria at Week 12. 4 placebo- and 2 adalimumab-treated patients switched to open-label adalimumab before Week 24. After 1 year of adalimumab treatment, 8 of 11 patients achieved an ASAS20 response. After 2 years, 6 of the remaining 8 patients with TSA reported an ASAS20 response. There were no serious adverse events or adverse event-related study discontinuations. CONCLUSION: In patients with TSA, adalimumab treatment resulted in rapid and clinically significant improvement in the signs and symptoms of active disease. Adalimumab effectiveness and safety were sustained for at least 2 years. TRIAL REGISTRATION NUMBER: NCT00085644.

Cost effectiveness of adalimumab for the treatment of ankylosing spondylitis in the United Kingdom.

OBJECTIVES: This study evaluated the cost effectiveness of adalimumab vs conventional therapy in patients with active ankylosing spondylitis (AS). METHODS: The analysis was based on pooled data from two Phase III studies of adalimumab in active AS. Patients with an inadequate response to >/=1 NSAID received adalimumab 40 mg every other week (n = 246) or placebo (n = 151) for 24 weeks. A microsimulation model was developed with patients being treated with adalimumab according to the International ASAS Consensus Statement and BSR guidelines. The pooled adalimumab data, as well as data from the Outcome Assessment in AS International Study (OASIS) database and the literature, were used to model patients' BASDAI and BASFI scores and costs and health-related quality of life associated with various degrees of disease activity. Costs (in 2004 British pound) of AS, drug, administration, monitoring, hospitalization and AEs were calculated from the perspective of the UK NHS. Discounting was applied at 3.5% per year for costs and benefits as per the NICE reference case for economic evaluations. Uncertainty was addressed via sensitivity analyses. RESULTS: The incremental cost-effectiveness ratio (ICER) of adalimumab vs conventional therapy was estimated to improve with longer time horizons (48 weeks to 5 and 30 yrs). The central estimate was that, over 30 yrs, adalimumab therapy yielded 1.03 more quality-adjusted life-years (QALYs) per patient initiating therapy. Some AS treatment-related costs were estimated to be offset by adalimumab (at 10,750 pounds/patient), leaving a total incremental cost (adalimumab vs conventional therapy) at 23,857 pounds per patient. The 30-yr ICER of adalimumab vs conventional therapy was estimated at 23 pounds 097/QALY. Sensitivity analyses demonstrated robustness of results. When indirect costs were also included (analysis from societal perspective), ICER improved to 5093 pounds/QALY. CONCLUSIONS: This analysis indicates that adalimumab, when used according to UK treatment guidelines, is cost-effective vs conventional therapy for treating AS patients.

RAD in stable lung and heart/lung transplant recipients: safety, tolerability, pharmacokinetics, and impact of cystic fibrosis.

BACKGROUND: RAD is a novel macrolide with potent immunosuppressive and antiproliferative activities. This study characterizes the safety, tolerability, and pharmacokinetics of two different single oral doses of RAD in stable lung and heart/lung transplant recipients with and without cystic fibrosis (CF). METHODS: This was a Phase I, multicenter, randomized, double-blind, two-period, two-sequence, crossover study. Single doses of RAD capsules at doses of 0.035 mg/kg (2.5 mg maximum) or 0.10 mg/kg (7.5 mg maximum) were administered with cyclosporine (Neoral [cyclosporine, USP] modified), steroids, and azathioprine on Day 1. The alternate dose was administered on Day 16. Laboratory assessments, vital signs, and adverse events were recorded throughout the study. RAD pharmacokinetic profiles were assessed over a 7-day period following each dose. Steady-state cyclosporine (CsA) profiles were assessed at baseline and with each RAD dose; RAD and CsA trough concentrations were obtained throughout the study period. RESULTS: Of the 20 patients randomized, 8 had CF and 12 did not. Single doses of RAD were safe and well tolerated. Headache was the most common side effect. RAD produced a mild, dose-dependent, reversible decrease in platelet and leukocyte counts. Cholesterol and triglycerides were minimally affected. At both doses, CF patients had significantly lower peak concentrations of RAD than did non-CF patients (p = 0.03); however, overall exposure (area under the curve/dose) was not different between the groups (p = 0.63). At the higher dose, there was a clinically minor under-proportionality in AUC, averaging -11%. Steady-state pharmacokinetics of CsA were not affected by RAD co-administration.RAD was safe and well tolerated by stable lung and heart/lung transplant recipients with and without CF. The presence of CF did not influence the extent of RAD exposure. Single doses of RAD did not affect the pharmacokinetics of CsA. Ongoing studies are assessing the long-term safety and efficacy of RAD in lung and heart/lung transplantation.

Embryonic XMab21l2 expression is required for gastrulation and subsequent neural development.

Cell fate determining gene mab-21 regulates the proper establishment of neural cell fate and sensory organ identity in nematode. Mammalian homologs of mab-21 have also been implicated to play critical roles in mid-, hindbrain and craniofacial differentiation. We report here the isolation of a mab-21 homolog, XMab21l2, from Xenopus. We showed that its expression in Xenopus was initiated at gastrulation and prominent signal was detected in neurulating embryos at the neural tube, the optic tissue, the developing midbrain, and the pharyngeal pouches. We demonstrated by RNA interference (RNAi), together with other antisense approaches, that XMab21l2 expression is required for the completion of gastrulation and subsequent neural development.

Effects of Gas-Phase Basicity on the Proton Transfer between Organic Bases and Trifluoroacetic Acid in the Gas Phase: Energetics of Charge Solvation and Salt Bridges.

The unimolecular dissociation pathways and kinetics of a series of protonated trimer ions consisting of two organic bases and trifluoroacetic acid were investigated using blackbody infrared radiative dissociation. Five bases with gas-phase basicities (GB) ranging from 238.4 to 246.2 kcal/mol were used. Both the dissociation pathways and the threshold dissociation energies depend on the GB of the base. Trimers consisting of the two most basic molecules dissociate to form protonated base monomers with an E(0) ~ 1.4 eV. Trimers consisting of the two least basic molecules dissociate to form protonated base dimers with an E(0) ~ 1.1-1.2 eV. These results indicate that the structures of the trimers change as a function of the GB of the basic molecule. The predominant structure of the protonated trimers consisting of the two most basic molecules is consistent with a salt bridge in which both of the basic molecules are protonated, and the trifluoroacetic acid molecule is deprotonated, whereas the predominant structure of the protonated trimers consisting of the two least basic molecules are consistent with charge-solvated complexes in which the proton is shared. The structure of the trimer consisting of the base of intermediate basicity is less clear; it dissociates to form primarily protonated base dimer, but has an E(0) ~ 1.2 eV. These results are consistent with the structure of this trimer as a salt bridge, but the resulting dissociation A(-). BH(+) product does not appear to be stable as an ion pair in the dissociative transition state.

Cyclosporine bioavailability of Neoral and Sandimmune in white and black de novo renal transplant recipients. Neoral Study Group.

Black renal transplant recipients have inferior graft outcomes when compared to whites. The relative bioavailability of cyclosporine (CsA) with the Sandimmune (SIM) formulation is lower in black recipients when compared to whites. To study relative CsA bioavailability in the Neoral formulation, 18 black and 78 white de novo renal transplant recipients were randomized in a multicenter, double-blind, parallel group study to receive either SIM or Neoral capsules twice a day for 12 weeks. After an overnight fast, CsA whole blood levels (TDx) were collected during 12 hours after the morning dose and 12 hours after the evening dose with a standardized meal. Pharmacokinetic profiles were obtained at the end of weeks 1, 4, 8, and 12. Initial CsA dose was 5 mg/kg twice a day; subsequent doses were titrated to target trough CsA levels. Area under the blood concentration vs. time curve (AUC), peak blood concentration (Cmax) and time to Cmax(Tmax) were obtained from 16 black and 73 white patients. Food conditions (fed and fasting) were averaged, and data was dose-normalized. For black recipients, Neoral was significantly more bioavailable than SIM only during week 1; there was also a consistent trend to higher cyclosporine bioavailability at weeks 4, 8, and 12. For whites, there were significant differences in favor of Neoral at all time periods. No significant differences in relative bioavailability were noted between races for either SIM or Neoral except for a higher Cmax in white patients given Neoral. Neoral is better absorbed than SIM in both blacks and whites. These data suggest that Neoral is the superior CsA preparation for all racial groups.

A phase I study of a 4-week course of SDZ-RAD (RAD) quiescent cyclosporine-prednisone-treated renal transplant recipients.

BACKGROUND AND METHODS: This phase I, randomized, blinded, placebo-controlled study assessed the safety profile and pharmacokinetics of a 4-week course of once-daily, sequential ascending doses (0.75, 2.5, or 7.5 mg/day) of SDZ-RAD (RAD) capsules in renal transplant recipients on a stable regimen of cyclosporine (CsA; Neoral) and prednisone. RESULTS: RAD displayed a similar spectrum of side effects as observed with rapamycin, namely, an increased incidence of infection associated with the augmented immunosuppression and a dose-related occurrence of thrombocytopenia, hypercholesterolemia, and hypertriglyceridemia, particularly at the 7.5-mg dose. The pharmacokinetic parameters of RAD showed dose proportionality, a good correlation between trough and area under the curve (AUC) concentrations, and a moderate accumulation of 2.5-fold. The drug was absorbed within 2 hr and displayed a 16-19-hr half-life, which is shorter than that of rapamycin. RAD reached steady state at 4 days. Preliminary kinetic-dynamic correlations indicate a correlation between thrombocytopenia (but not hyperlipidemia) and AUC, as well as maximum drug concentrations, and weight-adjusted dose. At the end of a 4-week course of simultaneous dosing, there was no evidence of a pharmacokinetic interaction between CsA and RAD. CONCLUSION: This study suggests that the shorter half-life of RAD compared to rapamycin may confer the benefits of rapid attainment of steady state and dissipation of effects upon drug cessation. Controlled, multicenter trials are being planned to assess the impact of these features on clinical outcomes.

Genomic cloning and chromosomal localization of the mouse Mab21l2 locus.

A second mouse gene related to the nematode mab-21 gene has been isolated. This gene, Mab21l2, encodes a transcript with an open reading frame discretely organized in a single exon. It shares 93.3% and 55.5% amino acid identity with the human and worm mab-21 respectively. FISH analysis determined that this gene is on chromosome 3 at a position between bands 3E3 and 3F1. This newly identified mouse gene will be useful in future examination of mab-21 gene function in vertebrate models.

Developmental expression of Mab21l2 during mouse embryogenesis.

mab-21 has been identified as a critical component required for sensory organ identity establishment in Caenorhabditis elegans. [Chow, K.L., Emmons, S.W., 1994. Development 120, 2579-2592; Chow, E. L., Hall, D.H., Emmons, S.W., 1995. Development 121, 3615-3625]. Human and mouse homologs of this gene have been isolated and their transcripts are predominantly detected in the eye and cerebellum [Margolis, R.L., Stine, O.C., McInnis, M.G., et al., 1996. Hum. Mol. Genet 5, 607-616; Mariani, M., Corradi, A., Baldessari, D., et al., 1998. Mech. Dev. 79, 131-135. We report here the expression profile of a second murine mab-21 homolog, Mab21l2 [Wong, R.L.Y., Wong, H.T., Chow, K.L., 1999. Cyto. Cell Genet., [in press]. Whole mount in situ hybridization data from embryonic day 8.5 to day 15 revealed that Mab21l2 expression patterns partially overlapped with that of Mab21l1. In addition, its strong expression in the mid- and hindbrain, otic vesicle, optic vesicle, maxillary and mandibular process, paraxial mesoderm, dorsal midline, limb bud and developing digits suggest that Mab21l2 has more diverse functions in vertebrate development.

Thyroid hormones regulate the expression of somatostatin receptor subtypes in the rat pituitary.

Circulating TSH levels are increased in hypothyroidism and suppressed in hyperthyroidism. On the other hand, the hypothalamic hormone somatostatin suppresses basal and TRH-induced TSH release, an effect which is enhanced by thyroid hormones. To investigate whether the effects of thyroid hormones on TSH secretion may be mediated in part through alterations in the gene expression of pituitary somatostatin receptors (SSTR), 3-week-old male Sprague-Dawley rats were rendered hypothyroid with antithyroid drugs for 3 weeks. Total RNA extracted from anterior pituitaries were analysed for SSTR mRNA levels, using Northern blot hybridization. Compared to controls, hypothyroid rats had significantly lower pituitary mRNA levels of SSTR1 and SSTR2 (p < 0.0001 for both, n = 16); the reductions could be prevented by T4 supplementation (3 microgram/100 g body weight/day i.p.). In vitro studies using GH4C1 rat pituitary cells showed that the addition of T3 10(-8) M to cells cultured in charcoal-stripped bovine calf serum resulted in significant increases in mRNA levels of SSTR1 (p < 0.0001; n = 7) and the two transcripts of SSTR2 (p < 0.0005; n = 7). The increase for SSTR1 showed no further increase with higher doses of T3, but was time-dependent and could be seen consistently after 8 h of incubation. We conclude that thyroid hormones regulate the gene expression of SSTR subtypes in the pituitary, via a direct action on anterior pituitary cells. Changes in SSTR gene expression may contribute to the increase in circulating TSH levels in hypothyroidism.

Improved cyclosporine bioavailability in black pediatric liver transplant recipients after administration of the microemulsion formulation.

Black transplant recipients are associated with low cyclosporine bioavailability, which may contribute to the poorer clinical outcomes observed with these patients. In this analysis, we compared cyclosporine exposure in black (n = 9) and nonblack (n = 18) pediatric maintenance liver transplant recipients by using steady-state pharmacokinetic profiles obtained after administration of the original and microemulsion formulations of cyclosporine. Treatment with the original cyclosporine formulation resulted in lower mean dose-normalized, area under the concentration-versus-time curve values for black compared with nonblack pediatric liver transplant recipients. On conversion to the microemulsion formulation of cyclosporine, black and nonblack patients experienced increases in cyclosporine bioavailability of 102% and 39%, respectively (P =.009 and P =.001). Because the increase in mean bioavailability was substantially greater for blacks, area under the concentration-versus-time curve values for this pediatric subpopulation became similar to those levels obtained for nonblacks receiving the microemulsion formulation for cyclosporine. When patients were further stratified by age, ethnic differences in bioavailability with the original formulation of cyclosporine were most apparent in the 1- to 5-year age group. Conversion to the microemulsion formulation resulted in a 164% increase (P =.05) in bioavailability for black patients within this age group such that, again, these levels became similar to area under the concentration-versus-time curve values obtained for young nonblacks receiving cyclosporine for microemulsion. Improvements in cyclosporine bioavailability after administration of the microemulsion formulation of cyclosporine may translate to improved long-term graft and patient outcomes for black pediatric liver transplant recipients.

Combination of bone marrow and TGF-beta1 augment the healing of critical-sized bone defects.

A 1.5 cm segmental defect in the radius of rabbits was used to compare healing at sites administered TGF-beta, with or without autologous bone marrow, to autogenous cortical bone graft. The carrier for TGF-beta consisted of tricalcium phosphate (TCP) granules and hetastarch. The efficacy of TGF-beta formulations and bone marrow (BM) was compared to autogenous bone, carrier control, and untreated defect sites. Bone measurements taken at necropsy included the anterior-posterior (AP) diameter and medial to lateral (LAT) diameter of the defect; the AP and LAT diameters of both radii measured 1 cm proximal to the distal epiphysis, and the AP and LAT diameters of the mid-shaft of the femora. The bones from each group were subdivided for either histological evaluation or for mechanical testing. Strength (maximum torque), energy, angle of rotation and stiffness were determined for both the treated and contralateral radii. Results of the radiographic, necropsy, and mechanical data for defects administered 1.0 microgram of TGF-beta1 + BM or autogenous cortical bone were similar and indicated superior healing compared to defects left blank or administered the carrier control with or without bone marrow. Defects administered 1.0 microgram of TGF-beta1 + BM or autogenous cortical bone had high mechanical strength relative to the control groups and were characterized histologically as healed primarily with lamellar bone. The results from the defects left blank or administered carrier control were similar and generally characterized by poor healing or nonunion. This study demonstrated substantial equality of healing between 1.0 microgram of TGF-beta1 + BM and autograft indicating that this formulation could function as a substitute for autologous grafts.

Optimal selection procedures for abbreviated area under the curve (AAUC) of blood concentration versus time for drug blood concentration levels.

It has become common to collect blood samples from patients for phase II/III clinical trials to investigate pharmacokinetic/pharmacodynamic relationships. However, the frequency of blood samples drawn from patients is limited due to clinical or pharmacoeconomic reasons. We discuss some sampling schemes for an immunosuppressive drug in phase III studies. Selection criteria and statistical approaches are discussed to select blood-sampling time points in four scenarios from a single study and from combined multiple studies: (1) Area under the curve (AUC) only without constraint, (2) AUC and Cmax simultaneously without constraint, (3) AUC only with constraint(s), and (4) AUC and Cmax simultaneously with constraint(s).

Equivalence of cyclosporine blood level assays in patients receiving cyclosporine microemulsion or cyclosporine. The Sandoz Neoral Study Group N103.

The more rapid absorption of the cyclosporin A (CyA) microemulsion formulation (Neoral, NEO) compared to Sandimmune (SIM) might bypass intestinal metabolism resulting in differing amounts of CyA metabolites in blood as compared to SIM. If true, then CyA levels obtained with a CyA monoclonal antibody assay (TDx) that has metabolite cross-reactivity might differ depending on the CyA formulation received by the patient, thereby affecting safety and efficacy. Fifty-one NEO vs. 50 SIM treated de novo renal transplant recipients from a multicenter double-blind randomized trial had morning, whole-blood, trough-samples obtained at the ends of weeks 1, 4, 8, and 12 post-transplant assayed for CyA by HPLC and TDx. The slopes (ratio of TDx value to HPLC value) for the regression lines between TDx and HPLC levels as a function of time post-transplant and CyA formulation were determined using a general linear model. For NEO, the slopes at each week (1.21-1.41 x HPLC) did not differ significantly (p = 0.82). For SIM, the week 1 slope (1.2) was significantly (p = 0.006) less than the other weeks (1.4-1.44). The slopes (NEO vs. SIM) were not different at either week 1 (1.21 vs. 1.22, p = 0.82) or at pooled weeks 4, 8, and 12 (1.33 vs. 1.4, p = 0.1). These results indicate that despite the improved absorption, TDx values obtained on NEO are qualitatively similar to those obtained on SIM.