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Acute heart failure syndromes (AHFS) are associated with the rapid onset of heart failure (HF) signs and symptoms. Hospitalizations for AHFS continue to rise and are associated with significant mortality and morbidity. Several pharmacological agents are currently approved for the treatment of AHFS, but their use is associated with an increase in short-term mortality. There is a need for new agents that can be given in the acute setting with increased efficacy and safety. Istaroxime is a unique agent with both inotropic and lusitropic properties which is currently being studied for the treatment of AHFS. Istaroxime inhibits the sodium-potassium adenosine triphosphatase (ATPase) and stimulates the sarcoplasmic reticulum calcium ATPase isoform 2 (SERCA-2) thereby improving contractility and diastolic relaxation. Early data from human studies reveal that istaroxime decreases pulmonary capillary wedge pressure (PCWP) and possibly improves diastolic function without causing a significant change in heart rate (HR), blood pressure, ischemic or arrhythmic events. Most commonly reported side effects were related to gastrointestinal intolerance and were dose related. In conclusion, istaroxime is a novel agent being investigated for the treatment of AHFS whose mechanism of action and cellular targets make it a promising therapy. Further studies with longer infusion times in patients with hypotension are required to confirm its efficacy and safety. [ABSTRACT FROM AUTHOR]

These studies were designed to compare the pharmacokinetic characteristics of a very highly purified urinary human follicle stimulating hormone (FSH-HP) preparation (sp. act. approximately 9000 IU FSH/mg of protein), Metrodin HP, with a standard urinary FSH preparation Metrodin (FSH). The two preparations were administered in a balanced, random-order, cross-over sequence as single doses of 150 IU, separated by 1 week of washout to 12 female volunteers by i.v. injection and to 12 male volunteers by i.m. and s.c. routes. FSH concentrations were measured by immunoradiometric assay and by an in-vitro rat granulosa cell aromatase bioassay. After an i.v. bolus, the pharmacokinetics of the two FSH preparations were identical. Total clearance was 0.5 and 0.15 l/h respectively for immunoassay and bioassay data. Immunoassay showed that the two preparations were similar for renal clearance (0.1 l/h), volumes of distribution at steady state (9 l), distribution and terminal half-lives (2 and 17 h, respectively). After parenteral administrations, the absorption half-life of FSH was approximately 3 h and the apparent terminal half-life was approximately 1.5 days. Both preparations had relative bioavailabilities close to 100% for i.m. and s.c. administrations. Immunopurification, which results in a very highly purified FSH-HP, does not modify the pharmacokinetic properties of FSH. This study also confirmed that s.c. and i.m. doses of FSH-HP are equivalent from the pharmacokinetic and pharmacodynamic points of view. [ABSTRACT FROM AUTHOR]

Background: The envelope protein of human endogenous retrovirus W (HERV-W-Env) is expressed by macrophages and microglia, mediating axonal damage in chronic active MS lesions., Objective and Methods: This phase 2, double-blind, 48-week trial in relapsing-remitting MS with 48-week extension phase assessed the efficacy and safety of temelimab; a monoclonal antibody neutralizing HERV-W-Env. The primary endpoint was the reduction of cumulative gadolinium-enhancing T1-lesions in brain magnetic resonance imaging (MRI) scans at week 24. Additional endpoints included numbers of T2 and T1-hypointense lesions, magnetization transfer ratio, and brain atrophy. In total, 270 participants were randomized to receive monthly intravenous temelimab (6, 12, or 18 mg/kg) or placebo for 24 weeks; at week 24 placebo-treated participants were re-randomized to treatment groups., Results: The primary endpoint was not met. At week 48, participants treated with 18 mg/kg temelimab had fewer new T1-hypointense lesions ( p  = 0.014) and showed consistent, however statistically non-significant, reductions in brain atrophy and magnetization transfer ratio decrease, as compared with the placebo/comparator group. These latter two trends were sustained over 96 weeks. No safety issues emerged., Conclusion: Temelimab failed to show an effect on features of acute inflammation but demonstrated preliminary radiological signs of possible anti-neurodegenerative effects. Current data support the development of temelimab for progressive MS., Trial Registration: CHANGE-MS: ClinicalTrials.gov: NCT02782858, EudraCT: 2015-004059-29; ANGEL-MS: ClinicalTrials.gov: NCT03239860, EudraCT: 2016-004935-18.

Aim: To report the first study of temelimab, a monoclonal antibody neutralizing the pathogenic human endogenous retrovirus type W envelope, in patients with type 1 diabetes (T1D)., Materials and Methods: This double-blind, placebo-controlled, randomized clinical trial recruited adult patients with T1D within 4 years postdiagnosis and remaining C-peptide secretion. Sixty-four patients were randomized (2:1) to monthly temelimab 6 mg/kg or placebo during 24 weeks followed by a 24-week, open-label extension, during which all patients received temelimab. The primary objective was the safety and tolerability of temelimab. The secondary objective was to assess the pharmacodynamics response such as C-peptide levels, insulin use, HbA1c, hypoglycaemia and autoantibodies., Results: Temelimab was well tolerated without any group difference in the frequency or severity of adverse events. Concerning exploratory endpoints, there was no difference in the levels of C-peptide, insulin use or HbA1c between treatment groups at weeks 24 and 48. The frequency of hypoglycaemia events was reduced with temelimab (P = 0.0004) at week 24 and the level of anti-insulin antibodies was lower with temelimab (P < 0.01); the other autoantibodies did not differ between groups., Conclusions: Temelimab appeared safe in patients with T1D. Pharmacodynamics signals (hypoglycaemia and anti-insulin antibodies) under temelimab were observed. Markers of β-cell functions were not modified by treatment. These results need to be further explored in younger patients with T1D with earlier disease onset., (© 2020 John Wiley & Sons Ltd.)

Purpose: Temelimab/GNbAC1 is a humanized immunoglobulin G4 monoclonal antibody antagonist of the human endogenous retrovirus W envelope protein, which is associated with multiple sclerosis (MS) pathophysiology and possibly with other autoimmune disorders. Human endogenous retrovirus W envelope protein is expressed in the central nervous system of patients with MS, and sufficient amount of temelimab must reach the target. The safety of very high dosages of temelimab should be tested to support further clinical trials in MS., Methods: This randomized, placebo-controlled, dose-escalation study evaluated the safety and pharmacokinetic profile of temelimab in 24 healthy volunteers after a single intravenous infusion at doses of 36, 60, 85, and 110 mg/kg administered sequentially., Findings: Temelimab was well tolerated, with no particular adverse drug reactions at any dose. The maximal dose of 110 mg/kg could be administered, and no antidrug antibodies were induced. After administration of 36-110 mg/kg, mean temelimab C max increased from 859 to 2450 μg/mL, and AUC values increased from 319,900 to 1,030,000 μg·h/mL. There was an approximate dose-proportional increase in exposure, similar to observations at lower doses., Implications: The favorable data in terms of safety and pharmacokinetic variables support temelimab use at high doses in future MS trials to optimally neutralize the temelimab target in the central nervous system. ClinicalTrials.gov identifier: NCT03574428., (Copyright © 2019. Published by Elsevier Inc.)

We describe a newly identified therapeutic target for type 1 diabetes (T1D): an envelope protein of endogenous retroviral origin, human endogenous retrovirus W envelope (HERV-W-Env). HERV-W-Env was found to be detected in the blood of ~60% of patients with T1D and is expressed in acinar pancreatic cells of 75% of patients with T1D at post mortem examination. Preclinical experiments showed that this protein displays direct cytotoxicity on human β-islet cells. In vivo HERV-W-Env impairs the insulin and glucose metabolism in transgenic mice expressing HERV-W-Env. GNbAC1, an IgG4 monoclonal antibody, has been developed to specifically target HERV-W-Env and to neutralize the effect of HERV-W-Env in vitro and in vivo. GNbAC1 is currently in clinical development for multiple sclerosis and > 300 subjects have been administered with GNbAC1 so far. GNbAC1 is now being tested in T1D in the RAINBOW-T1D study, which is a randomized placebo-controlled study with the objective of showing the safety and pharmacodynamic response of GNbAC1 in patients who have had T1D with a maximum of 4 years' duration. GNbAC1 is being tested vs placebo at the dose of 6 mg/kg in 60 patients during six repeated administrations for 6 months; a 6-month open-label extension will follow. The primary endpoint is to assess safety, and secondary endpoints are the pharmacodynamic responses to GNbAC1. GNbAC1 targeting HERV-W-Env is currently in clinical development in T1D, with the first safety and pharmacodynamic study. If the study results are positive, this may open the door to the development of an innovative non-immunomodulatory disease-modifying treatment for T1D., (© 2018 John Wiley & Sons Ltd.)

Background: GNbAC1, a humanized monoclonal antibody, is an innovative treatment currently in development for multiple sclerosis (MS) which, contrary to the immunomodulation/immunosuppressive mechanism of action of most of the MS drugs, targets specifically a protein of endogenous retroviral origin supposed to be critical in MS pathogenesis., Methods: This trial is a randomized placebo controlled 4-arm study with the objective of demonstrating the efficacy of repeated doses of GNbAC1 on the cumulative number of T1 Gd-enhancing lesions measured from Week 12 to 24 in patients with relapsing remitting MS (RRMS). Two hundred sixty patients with RRMS are planned to be included. Three doses of GNbAC1 will be tested versus placebo: 6mg/kg, 12mg/kg and 18mg/kg, administered intravenously, with 4-week administration intervals. The design is based on the classic 24-week placebo-controlled repeated brain MRI trial design (Period 1), with an extension of 24 weeks during which placebo patients will be re-randomized to one of the three doses of GNbAC1 to assess efficacy and safety of prolonged treatment of GNbAC1 (Period 2). The primary endpoint is the cumulative number of new Gadolinium enhanced T1 lesions measured using repeated brain magnetic resonance imaging (MRI) scans from Week 12 to 24; secondary endpoints, including additional MRI and clinical endpoints, will be assessed at the end of both Periods 1 and 2. Pharmacokinetics and biomarkers will be assessed in serum in all patients at several time points and also in cerebrospinal fluid in a subgroup of patients. To alleviate potential ethical concerns regarding placebo administration in MS, an early escape from trial will be implemented for patients with a worsening clinical condition during trial., Conclusion: This dose-finding study should provide the first proof-of-concept of an innovative therapeutic approach for MS. The constraints of using a placebo group in RRMS patients while optimizing the trial power to evidence a new mechanism of action is discussed., (Copyright © 2016 Elsevier B.V. All rights reserved.)

GNbAC1 is a humanized IgG4 monoclonal antibody antagonist of Mulitple Sclerosis Retrovirus Envelope (MSRV-Env), a protein that could play a critical role in multiple sclerosis. This randomized placebo-controlled dose-escalation study evaluated the safety and pharmacokinetics of GNbAC1 in 21 healthy volunteers after single intravenous infusion at doses of 6, 18 and 36 mg/kg. Lumbar punctures were performed at days 2, 15 or 29 to measure GNbAC1 concentrations in cerebrospinal fluid (CSF). GNbAC1 was well tolerated. Serum data show a dose-linear pharmacokinetics. A mean CSF/serum ratio of 0.12% was observed at Day 2, increasing to 0.39% at Day 15 and 0.42% at Day 29. Linear regression analysis shows a relationship between GNbAC1 CSF/serum ratio and albumin CSF/serum ratio and a relationship at the limit of statistical significance with the timing of CSF sampling.

Human endogenous retroviruses (HERV) represent about 8 % of the human genome. Some of these genetic elements are expressed in pathological circumstances. A HERV protein, the multiple sclerosis-associated retrovirus (MSRV) envelope protein (MSRV-Env), is expressed in the blood and active brain lesions of multiple sclerosis (MS) patients. It possesses pro-inflammatory and myelinotoxic properties. The patterns of expression and pathogenic properties of MSRV-Env make it a relevant drug target for MS therapeutics-in particular for preventing neurodegeneration, a key component of progressive forms of MS. An immunoglobulin G4 monoclonal antibody (mAb), called GNbAC1, has been developed to neutralize this pathogenic target. After showing neutralizing effects in vitro and in mouse models of MS, GNbAC1 is now in phase II clinical development. MSRV-related biomarkers such as MSRV-Env and MSRV polymerase (MSRV-Pol) gene transcripts are overexpressed in the blood and cerebrospinal fluid of patients with MS. These biomarkers may have prognostic value for long-term MS evolution, and their transcription levels in blood decline during treatments with GNbAC1, which has also been reported in patients administered reference MS drugs such as natalizumab or interferon-β. GNbAC1 as a new MSRV-Env-antagonist mAb could be a specific and causal treatment for MS, with a particular application for progressive forms of the disease. For possible use in companion diagnostic tests, MSRV-associated biomarkers could open the door to a personalized therapeutic approach for MS.

GNbAC1 is a humanized monoclonal antibody targeting MSRV-Env, an endogenous retroviral protein, which is expressed in multiple sclerosis (MS) lesions, is pro-inflammatory and inhibits oligodendrocyte precursor cell differentiation. This paper describes the open-label extension up to 12months of a trial testing GNbAC1 in 10 MS patients at 2 and 6mg/kg. The primary objective was to assess GNbAC1 safety, and other objectives were pharmacokinetic and pharmacodynamic assessments. During the extended study, no safety issues occurred in the 8 remaining patients. No anti-GNbAC1 antibodies were detected. GNbAC1 appears well tolerated., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Background: GNbAC1 is an immunoglobulin (IgG4) humanised monoclonal antibody against multiple sclerosis-associated retrovirus (MSRV)-Env, a protein of endogenous retroviral origin, expressed in multiple sclerosis (MS) lesions, which is pro-inflammatory and inhibits oligodendrocyte precursor cell differentiation., Objective: This is a randomised, double-blind placebo-controlled dose-escalation study followed by a six-month open-label phase to test GNbAC1 in MS patients. The primary objective was to assess GNbAC1 safety in MS patients, and the other objectives were pharmacokinetic and pharmacodynamic assessments., Methods: Ten MS patients were randomised into two cohorts to receive a single intravenous infusion of GNbAC1/placebo at doses of 2 or 6 mg/kg. Then all patients received five infusions of GNbAC1 at 2 or 6 mg/kg at four-week intervals in an open-label setting. Safety, brain magnetic resonance imaging (MRI), pharmacokinetics, immunogenicity, cytokines and MSRV RNA expression were studied., Results: All patients completed the study. GNbAC1 was well tolerated in all patients. GNbAC1 pharmacokinetics is dose-linear with mean elimination half-life of 27-37 d. Anti-GNbAC1 antibodies were not detected. Cytokine analysis did not indicate an adverse effect. MSRV-transcripts showed a decline after the start of treatment. Nine patients had stable brain lesions at MRI., Conclusion: The safety, pharmacokinetic profile, and pharmacodynamic responses to GNbAC1 are favourable in MS patients over a six-month treatment period., (© The Author(s) 2014.)

Monoclonal antibodies (mAbs) play an increasing important role in the therapeutic armamentarium against multiple sclerosis (MS), an inflammatory and degenerative disorder of the central nervous system. Most of the mAbs currently developed for MS are immunomodulators blocking the inflammatory immune process. In contrast with mAbs targeting immune function, GNbAC1, a humanized IgG4 mAb, targets the multiple sclerosis associated retrovirus envelope (MSRV-Env) protein, an upstream factor in the pathophysiology of MS. MSRV-Env protein is of endogenous retroviral origin, expressed in MS brain lesions, and it is pro-inflammatory and toxic to the remyelination process, by preventing the differentiation of oligodendrocyte precursor cells. We present the preclinical and early clinical development results of GNbAC1. The specificity of GNbAC1 for its endogenous retroviral target is described. Efficacy of different mAb versions of GNbAC1 were assessed in MSRV-Env induced experimental allergic encephalitis (EAE), an animal model of MS. Because the target MSRV-Env is not expressed in animals, no relevant animal model exists for a proper in vivo toxicological program. An off-target 2-week toxicity study in mice was thus performed, and it showed an absence of safety risk. Additional in vitro analyses showed an absence of complement or antibody-dependent cytotoxicity as well as a low level of cross-reactivity to human tissues. The first-in-man clinical study in 33 healthy subjects and a long-term clinical study in 10 MS patients showed that GNbAC1 is well tolerated in humans without induction of immunogenicity and that it induces a pharmacodynamic response on MSRV biomarkers. These initial results suggest that the mAb GNbAC1 could be a safe long-term treatment for patients with MS with a unique therapeutic mechanism of action.

Unlabelled: The anti-hepatitis C virus (HCV) effect and safety of three different oral doses of the cyclophilin inhibitor Debio 025 in combination with pegylated interferon-alpha2a (PEG IFN-alpha2a) were investigated in a multicenter, randomized, double-blind, placebo-controlled escalating dose-ranging phase II study in treatment-naïve patients with chronic hepatitis C. Doses of 200, 600, and 1,000 mg/day Debio 025 in combination with PEG IFN-alpha2a 180 microg/week for 4 weeks were compared with monotherapy with either 1,000 mg/day Debio 025 or 180 microg/week PEG IFN-alpha2a. In patients with genotypes 1 and 4, the 600- and 1,000-mg combination treatments induced a continuous decay in viral load that reached -4.61 +/- 1.88 and -4.75 +/- 2.19 log(10) IU/mL at week 4, respectively. In patients with genotypes 2 and 3, HCV RNA levels at week 4 were reduced by -5.91 +/- 1.11 and -5.89 +/- 0.43 log(10) IU/mL, respectively, with the same treatment regimens. Adverse events were comparable between treatment groups apart from a higher incidence of neutropenia associated with PEG IFN-alpha2a and an increased incidence of isolated hyperbilirubinemia at the highest dose of Debio 025 (1,000 mg/day)., Conclusion: These results confirm that Debio 025 has a potent activity and an additive effect on HCV RNA reduction in genotype 1 and 4 patients at 600 and 1,000 mg/day when combined with PEG IFN-alpha2a.

Unlabelled: Debio-025 is an oral cyclophilin (Cyp) inhibitor with potent anti-hepatitis C virus activity in vitro. Its effect on viral load as well as its influence on intracellular Cyp levels was investigated in a randomized, double-blind, placebo-controlled study. Mean hepatitis C viral load decreased significantly by 3.6 log(10) after a 14-day oral treatment with 1200 mg twice daily (P < 0.0001) with an effect against the 3 genotypes (1, 3, and 4) represented in the study. In addition, the absence of viral rebound during treatment indicates that Debio-025 has a high barrier for the selection of resistance. In Debio-025-treated patients, cyclophilin B (CypB) levels in peripheral blood mononuclear cells decreased from 67 +/- 6 (standard error) ng/mg protein (baseline) to 5 +/- 1 ng/mg protein at day 15 (P < 0.01)., Conclusion: Debio-025 induced a strong drop in CypB levels, coinciding with the decrease in hepatitis C viral load. These are the first preliminary human data supporting the hypothesis that CypB may play an important role in hepatitis C virus replication and that Cyp inhibition is a valid target for the development of anti-hepatitis C drugs.

The pharmacokinetics and pharmacodynamics of recombinant human chorionic gonadotrophin (rHCG) were investigated in three studies of healthy volunteers. After single intravenous doses of 25, 250 and 1000 microg, rHCG and urinary HCG (uHCG) showed linear pharmacokinetics described by a bi-exponential model, although the area under the curve (AUC) for uHCG was ~29% lower than for rHCG. After intramuscular or subcutaneous administration (absolute bioavailability, 40-50% for both), rHCG pharmacokinetics could be described by a first-order absorption, one-compartment model. During multiple subcutaneous dosing, the amount of HCG increased by approximately1.7-fold. A comparison of liquid and freeze-dried rHCG and freeze-dried uHCG showed pharmacokinetic bioequivalence. In down-regulated male subjects, single doses of 125 microg rHCG, given intravenously, intramuscularly or subcutaneously, produced comparable increases in serum testosterone, inhibin and 17beta-oestradiol, with little further increase during repeated subcutaneous administration (in female subjects, this produced a sustained comparable increase in serum androstenedione and testosterone concentrations). In conclusion, the pharmacokinetics and pharmacodynamics of rHCG are similar to those of uHCG and are not affected by the use of different formulations. In healthy subjects, rHCG produces pharmacodynamic responses consistent with HCG physiology and is suitable for use in the same clinical indications as uHCG. The secured source and high purity of rHCG may offer important advantages.

Dehydroepiandrosterone (DHEA; 50 and 25 mg) and placebo tablets were orally administered daily to 24 healthy aging men and women (67.8 +/- 4.3 yr) for 8 days according to a balanced incomplete block design. Nine blood tests on both the first and eighth days allowed the measurement of DHEA, its sulfate DHEAS, and metabolites: testosterone, 5alpha-androstan-3alpha,17beta-diol glucuronide, estradiol, and estrone. Relatively low background levels of DHEA(S) were observed, and with the reestablishment of "young" levels, four important results were obtained. 1) Blood DHEA had an apparent terminal half-life of more than 20 h, the same order of magnitude as that of blood DHEAS, a result explainable by back-hydrolysis of the large amount of DHEAS formed after oral administration of DHEA, a mechanism providing long-lived unconjugated DHEA and metabolites. 2) The metabolic conversion of DHEAS to DHEA was significantly greater in women than in men. 3) No accumulation of steroids was observed. 4) No worrying transformation to androgen and estrogen was recorded; indeed, the limited increased estradiol in aged women could be predicted to be beneficial. These results suggested that daily oral administration of DHEA (25/50 mg) is safe in elderly subjects. The 50-mg dose was chosen for a 1 yr, double blind, placebo-controlled trial of daily oral administration of DHEA in 60- to 80-yr-old individuals (DHEAge).

Chorionic gonadotropin (CG) is a glycoprotein hormone, whose action is mediated by the luteinizing hormone/CG receptor. Testosterone concentrations from six pituitary-desensitized, healthy male volunteers were obtained after four different administrations of recombinant-human CG (rhCG). We present a modeling study to provide a possible explanation for the observations that increased exposure to rhCG induces higher and then lower testosterone concentrations and that marked rebound effects are observed at the end of repeated administration of rhCG. We used semimechanistic models (in which flexible functions represent unknown parts of the models) to identify the relationship of rhCG concentrations to the testosterone levels. Based on the results obtained with the semimechanistic models, different mechanistic down-regulation models were devised and tested. The final model uses a one-compartment model to describe the endogenous production rate of testosterone; rhCG affects the production rate with a mechanism consistent with a two-site binding site, with effect proportional to one-site bound concentration. The modeling results indicate that when rhCG concentration increases, the testosterone production rate increases to 45 times the baseline value. However, at an rhCG concentration of more than about 30 IU/liter, the production rate decreases. Simulations showed that both dose and dosing interval profoundly influence testosterone response to rhCG.

Objective: To assess the pharmacokinetics of a recombinant human LH preparation and its pharmacokinetic and pharmacodynamic interactions with recombinant human follicle-stimulating hormone (FSH)., Design: Prospective, randomized cross-over study., Setting: Phase I clinical research environment., Patient(s): Twelve healthy pituitary down-regulated females., Intervention(s): Subjects received 150 IU of s.c. recombinant human LH and FSH, either alone or in combination, followed by recombinant human LH and FSH once daily for 7 days., Main Outcome Measure(s): Pharmacokinetic parameters, ovarian follicle development., Result(s): No pharmacokinetic interaction between recombinant human LH and FSH was observed, with no significant difference in baseline-corrected maximal observed concentration over baseline, area under the concentration-time curve from t = 0 to t = 24 hours, or time to maximal concentration after single doses alone or in combination. After daily administration, the mean accumulation ratio was 1.6 for LH and 2.9 for FSH, with absorption and terminal phase half-life estimates of 4 and 11 hours for LH and 8 and 16 hours for FSH, respectively. Combined administration of FSH and LH for 7 days was effective in stimulating ovarian follicular development and steroidogenesis, with large interindividual variability related to ovarian sensitivity., Conclusion(s): A new recombinant human LH preparation has a low accumulation ratio at steady-state and no pharmacokinetic or pharmacodynamic interactions with recombinant human FSH.

Objective: To assess the pharmacokinetics after i.v. administration of a recombinant human LH and to compare them to those of a reference hMG preparation containing urinary human LH., Design: Prospective, dose-escalating, cross-over study., Setting: Phase I clinical research environment., Patient(s): Twelve healthy pituitary down-regulated females., Intervention(s): Subjects received single i.v. doses of 300, 10,000, and 40,000 IU of recombinant human LH, followed by a single i.v. dose of 300 IU of hMG, all separated by 1 week., Main Outcome Measure(s): Pharmacokinetic parameters., Results: For both preparations, LH serum levels were well described by similar biexponential models. The pharmacokinetics of recombinant human LH were linear over the 300 to 40,000 IU range. After a rapid distribution phase with an initial half-life of 1 hour, both recombinant human LH and urinary human LH were eliminated with a terminal half-life of 10-12 hours. Total serum clearance was 1.7 L/h with < 4% and 30% of the dose being eliminated in the urine for recombinant human LH and urinary human LH, respectively. The volume of distribution at steady-state was approximately 10 L. Irrespective of the dose, recombinant human LH was well tolerated., Conclusion(s): The pharmacokinetics of recombinant human LH are linear with dose and similar to those of urinary human LH.

Objective: To assess the single-dose pharmacokinetics of a recombinant human LH preparation administered by the i.v., i.m., and s.c. route., Design: Prospective, randomized cross-over study., Setting: Phase I clinical research environment., Patient(s): Twelve healthy pituitary down-regulated females., Intervention(s): Subjects received single i.v., i.m., and s.c. doses of 10,000 IU of recombinant human LH, each separated by 1 week., Main Outcome Measure(s): Pharmacokinetic parameters., Result(s): After single i.v. administration, the pharmacokinetics were described by a two-compartment model, after i.m. or s.c. administration, by a one-compartment model with zero order absorption and a lag time. Using the immunoassay, after i.v. administration initial half-life was 1 hour and terminal half-life was 10 hours (half-life was prolonged after extravascular administration, suggesting rate-limiting absorption). Total serum clearance was 2.6 L/h, and steady, state volume of distribution was 14 L. Observed Cmax, after i.m. and s.c. administration, was 43 IU/L with median tmax of 9 hours (i.m.) and 5 hours (s.c.). Bioavailability was 0.54 (i.m.) and 0.56 (s.c.). The pharmacokinetics of LH are comparable using an in vitro bioassay., Conclusion(s): The terminal half-life of recombinant human LH is around 12 hours and is slightly prolonged after extravascular administration. The pharmacokinetics are similar after i.m. and s.c. injection, and one-half the administered dose is available systemically.

Objective: To assess and compare the pharmacokinetics of recombinant human FSH with those of a reference preparation of urinary human FSH., Design: Urinary human FSH and recombinant human FSH (Metrodin and Gonal-F; Laboratoires Serono, Aubonne, Switzerland) were administered in a balanced, random order, crossover sequence as a single i.v. dose of 150 or 300 IU separated by 1 week of washout to 12 pituitary down-regulated, healthy female volunteers. Serum FSH concentrations were measured by an immunoradiometric assay (IRMA) and by an in vitro rat granulosa cell aromatase bioassay. Urine FSH concentrations were measured by IRMA., Results: The mean concentration-time profiles after 150 IU of urinary human FSH and recombinant human FSH were superimposed, and the mean profile after 300 IU of recombinant human FSH was double that of the 150 IU dose. The data for both FSH preparations were well described by a biexponential equation. Total clearance of the preparations was comparable, judging from immunoassay and bioassay data (0.5 and 0.15 L/h, respectively). Based on the immunoassay, renal clearance of urinary human FSH was 0.1 L/h, whereas for recombinant human FSH it was slightly lower at 0.07 L/h, indicating that less than one fifth of the administered dose was excreted in the urine. Immunoassay showed that the two preparations were similar in terms of initial and terminal half-lives (2 and 17 hours, respectively). The volumes of distribution at steady state (11 L) were similar. The results of the in vitro bioassay confirmed this pharmacokinetic analysis. Just after i.v. administration, an initial decrease in the serum bioassay:immunoassay ratio was observed because of dilution of urinary human FSH or of recombinant human FSH in the residual endogenous FSH pool. Then the ratio increased progressively with time, suggesting either metabolic selection or activation of both types of injected human FSH toward forms with greater in vitro bioactivity. The bioassay:immunoassay ratio returned to baseline by day 7., Conclusion: The results obtained in this study indicate that the following [1] the pharmacokinetic characteristics of recombinant human FSH are similar to those of urinary human FSH; [2] the terminal half-life of human FSH is approximately 1 day; [3] after a single i.v. injection of human FSH a progressive increase in FSH bioassay: immunoassay ratio is observed; and [4] clinical use of recombinant human FSH could follow protocols and treatment regimens currently applied to urinary human FSH.

Objective: To assess the single-dose pharmacokinetics of a recombinant human FSH preparation (Gonal-F; Laboratoires Serono, Aubonne, Switzerland), administered by i.v., IM, and SC routes and its pharmacokinetics at steady state after multiple dosing by the SC route., Design: Twelve healthy down-regulated female volunteers received in random order three single doses of recombinant human FSH (150 IU, i.v., IM, and SC), with each administration separated by 1 week. The volunteers then received multiple recombinant human FSH doses by the SC route (150 IU one time per day) for 7 days. Follicle-stimulating hormone concentrations were measured by an immunoradiometric assay and an in vitro granulosa cell aromatase bioassay., Results: After a single administration, the pharmacokinetics of recombinant human FSH were well-described by a two-compartment model after i.v. administration and by a one-compartment model with first order absorption after IM or SC administration. The mean total clearance of FSH was approximately 0.6 L/h, and renal clearance accounted for one tenth of the total elimination after i.v. administration. The distribution half-life was close to 2 hours. The terminal half-life was nearly 1 day when estimated either by modeling the i.v. data set or from analysis of the terminal phase of the steady state pharmacokinetic curve or from the time taken to reach steady state after repeated SC administrations. After single IM and SC injection, two thirds of the administered dose was available systemically. The cumulation factor for repeated SC administration was approximately 3 when steady state was reached. The in vitro bioassay data confirmed these estimations. The temporal evolution of the bioassay:immunoassay ratio suggests either metabolic selection or activation of recombinant human FSH toward forms with greater in vitro bioactivity., Conclusion: The estimation of the elimination half-life of approximately 1 day indicates that the maximal effect of a given dose of recombinant human FSH administered daily cannot be observed until 3 to 4 days of repeated administration. This indicates that, on a pure pharmacokinetic basis, physicians should wait at least 4 days to assess the efficacy of a given dose of recombinant human FSH and that they should not modify dosage too frequently.

Objective: To investigate the respective role of the pharmacokinetic and of the pharmacodynamic characteristics in individual variability and to reassess the time course and the informative value of FSH pharmacodynamic markers by applying a combined pharmacokinetic-pharmacodynamic modeling analysis., Design: After a 1-week SC administration of 150 IU/d of recombinant human FSH (Gonal-F; Laboratoires Serono, Aubonne, Switzerland) to 12 healthy down-regulated female volunteers, inhibin and E2 serum level and total follicular volume were recorded at preset times during 2 weeks., Results: Good correlations were obtained between inhibin maximal levels and maximal total follicular volumes and between E2 maximal serum level increases and maximal total follicular volumes. In contrast, no correlation was found between maximal serum concentration of FSH and any of the recorded effects. Pharmacodynamic effects started to increase significantly later than FSH serum concentration, especially for E2 serum level and total follicular volume. Inhibin serum level was the first pharmacodynamic marker to increase. A full pharmacokinetic-pharmacodynamic model was developed to determine the relationship between drug concentrations and FSH pharmacological effects. This approach provides a better understanding of the concentration-effect relationship and should allow a rational design for recombinant human FSH dose regimen. The average equilibration half-life between serum concentrations and theoretical effect-compartment concentrations is approximately 2 days for inhibin and approximately 4 days for E2, indicating that inhibin serum levels are tracking FSH concentrations more closely than E2 serum levels., Conclusions: [1] Recombinant human FSH alone is effective to stimulate ovarian follicular development and steroidogenesis in women pretreated with a GnRH agonist despite complete LH suppression; [2] there is a large interindividual variability in the response to recombinant human FSH; [3] this variability is mainly related to ovarian sensitivity to FSH rather than difference in pharmacokinetics; [4] inhibin is an early index of follicular development, further supporting its role as a putative tool to monitor FSH therapy; and [5] a slow stepwise increase in FSH dose is recommended if FSH overexposure and excessive ovarian stimulation are to be minimized. These observations suggest that recombinant human FSH will in the near future replace urinary human FSH in the clinics.

The antinociceptive effect of three antidepressants with different postulated modes of action, 75 mg desipramine, 225 mg fluvoxamine, and 450 mg moclobemide, was evaluated after single oral dosing in a randomized, double-blind, placebo-controlled crossover study in 10 healthy volunteers. Experimental pain thresholds (polysynaptic R-III reflex and subjective pain rating) were monitored over 23 hours. Compared with placebo, all drugs induced significant subjective pain threshold increases (maximal increase: desipramine, +20%; fluvoxamine, +17%; moclobemide, +13%). However, only desipramine (maximal increase, +25%) and moclobemide (maximal increase, +14%) displayed a significative effect on R-III threshold. Antidepressants thus exert an antinociceptive effect after a single oral dose. The level of their action apparently relies on the postulated mode of action.

Recombinant human follicle stimulating hormone (r-hFSH; Gonal-F) is a new human FSH produced by a genetically engineered mammalian cell line (Chinese Hamster Ovary cells). To assess and compare its pharmacokinetics with urofollitropin (u-hFSH; Metrodin), extracted from the urine of postmenopausal women, we performed a cross-over study in 12 monkeys. They received 10 IU/kg iv of u-hFSH and r-hFSH. Then all received a single 10 IU/kg dose im and sc of r-hFSH. In the third phase, six monkeys received 10 IU/kg/day im of r-hFSH for 7 days when the six others received the same regimen subcutaneously. Blood was withdrawn at predetermined time points, and FSH serum concentrations were measured by an immunoenzymetric assay. Data were analyzed individually by fitting a two-compartment pharmacokinetic model for the intravenous routes and a one-compartment first-order absorption model for the intramuscular and subcutaneous routes. After intravenous administration of u-hFSH and r-hFSH, mean FSH concentration-time curves were almost parallel. AUC0-infinity was significantly smaller after r-hFSH (846 IU.hr-1/liter +/- 125) than after u-hFSH (1377 IU.hr-1/liter +/- 236) (p < 0.005; analysis of variance), because the u-hFSH immunological dose was greater (8.77 IU/kg) than the r-hFSH immunological dose (6.94 IU/kg). Thus total clearance for r-hFSH (0.008 liter/hr/kg +/- 0.001) and for u-hFSH (0.007 liter/hr/kg +/- 0.001) was almost similar. Distribution half-lives (1.5 hr +/- 0.1 and 1.8 hr +/- 0.4) and terminal half-lives (15.3 hr +/- 3.8 and 15.5 hr +/- 5.1) for r-hFSH and u-hFSH were similar.(ABSTRACT TRUNCATED AT 250 WORDS)

Iodinated natural human urinary tumor necrosis factor binding protein I (125I-uTBP) was iv injected into BALB/c mice, and its pharmacokinetics and tissue distribution were assessed during a short-term (0-1 hr) and for a long-term (0-24 hr) period. The blood 125I-uTBP concentration displayed a biphasic pattern that was adequately described by a biexponential function with estimated half-lives of 0.1 and 3.8 hr. The apparent volume of distribution (Vc) of the central compartment was 3 ml, which approximated the mouse blood volume. The clearance (CL) derived either from a model-dependent or a model-independent method of analysis was 2.5 and 2.9 ml/hr, respectively. One hr after the iv administration of 125I-uTBP, the radioactivity accumulated in the major organs and tissues. The highest concentrations in terms of pg per organ were seen in the skin and in the liver. When expressed as pg 125I-uTBP per mg organ, the distribution was the highest in the gallbladder, bladder, kidneys, and lungs. At 24 hr, the distribution of 125I-uTBP represented about 10% of the amount measured at 1 hr. The rank order of accumulation of the radiolabeled uTBP in the major organs, expressed as pg per organ at 24 hr was skin greater than liver greater than kidneys greater than lungs greater than gut greater than spleen greater than gallbladder.