Search Results

You are looking at 11 - 20 of 22 items for

  • Author: Christian J Strasburger x
Clear All Modify Search
Free access

Alexandra Keller, Zida Wu, Juergen Kratzsch, Eberhard Keller, Werner F Blum, Astrid Kniess, Rainer Preiss, Jens Teichert, Christian J Strasburger and Martin Bidlingmaier

Objective: Pharmacokinetic and pharmacodynamic data after recombinant human GH (rhGH) administration in adults are scarce, but necessary to optimize replacement therapy and to detect doping. We examined pharmacokinetics, pharmacodynamics, and 20 kDa GH after injection of rhGH at different doses and routes of administration.

Design: Open-label crossover study with single boluses of rhGH.

Methods: Healthy trained subjects (10 males, 10 females) received bolus injections of rhGH on three occasions: 0.033 mg/kg s.c., 0.083 mg/kg s.c., and 0.033 mg/kg i.m. Concentrations of 22 and 20 kDa GH, IGF-I, and IGF-binding proteins (IGFBP)-3 were measured repeatedly before and up to 36 h after injection.

Results: Serum GH maximal concentration (C max) and area under the time-concentration curve (AUC) were higher after i.m. than s.c. administration of 0.033 mg/kg (C max 35.5 and 12.0 μ g/l; AUC 196.2 and 123.8). C max and AUC were higher in males than in females (P < 0.01) and pharmacodynamic changes were more pronounced. IGFBP-3 concentrations showed no dose dependency. In response to rhGH administration, 20 kDa GH decreased in females and remained suppressed for 14–18 h (low dose) and 30 h (high dose). In males, 20 kDa GH was undetectable at baseline and throughout the study.

Conclusions: After rhGH administration, pharmacokinetic parameters are mainly influenced by route of administration, whereas pharmacodynamic variables and 20 kDa GH concentrations are determined mainly by gender. These differences need to be considered for therapeutic use and for detection of rhGH doping.

Free access

Susanna Wiegand, Anna Richardt, Thomas Remer, Stefan A Wudy, Jeremy W Tomlinson, Beverly Hughes, Annette Grüters, Paul M Stewart, Christian J Strasburger and Marcus Quinkler

Objective: The incidence of childhood obesity and type 2 diabetes has reached epidemic proportions. Glucocorticoid excess causes central obesity and diabetes mellitus as seen in Cushing’s syndrome. The 11β-hydroxysteroid dehydrogenase type 1 enzyme (11β-HSD1) regenerates active cortisol from inactive cortisone. Altered 11β-HSD1 may cause tissue-specific Cushing’s syndrome with central obesity and impaired glucose homeostasis.

Design, patients, and methods: Clinical and laboratory characteristics, and anthropometric measurements were determined in 15 male and 6 female obese pubertal children (aged 12–18 years, Tanner stages 2–5). In addition, analyses of 24-h excretion rates of glucocorticoids were also performed in 21 age-, sex-, and pubertal stage-matched non-obese children using gas chromatographic–mass spectrometric (GC–MS) analysis.

Results: 11β-HSD1 activity (urinary tetrahydrocortisol (THF) + 5α-THF/tetrahydrocortisone (THE) ratio) was lower in obese when compared with non-obese boys. In addition, obese children had a higher total cortisol metabolite excretion than non-obese children. 11β-HSD1 activity was significantly related to age in lean and obese children. Standard deviation score (SDS)-body mass index did not correlate with 11β-HSD1 activity, or with total cortisol metabolite excretion within each group. In obese children, 11β-HSD1 activity and total cortisol metabolite excretion showed no correlation to waist-to-hip ratio, fat mass (percentage of body mass), or the homeostasis model assessment of insulin resistance index.

Conclusions: In conclusion, our findings strongly suggest that 11β-HSD1 activity increases with age, and is reduced in obese boys. In addition, obese children have a higher total cortisol metabolites excretion suggesting a stimulated hypothalamus–pituitary–adrenal axis.

Open access

Christian J Strasburger, Niki Karavitaki, Sylvère Störmann, Peter J Trainer, Ilonka Kreitschmann-Andermahr, Michael Droste, Márta Korbonits, Berit Feldmann, Kathrin Zopf, Violet Fazal Sanderson, David Schwicker, Dana Gelbaum, Asi Haviv, Martin Bidlingmaier and Nienke R Biermasz

Background

Long-acting somatostatin analogues delivered parenterally are the most widely used medical treatment in acromegaly. This patient-reported outcomes survey was designed to assess the impact of chronic injections on subjects with acromegaly.

Methods

The survey was conducted in nine pituitary centres in Germany, UK and The Netherlands. The questionnaire was developed by endocrinologists and covered aspects of acromegaly symptoms, injection-related manifestations, emotional and daily life impact, treatment satisfaction and unmet medical needs.

Results

In total, 195 patients participated, of which 112 (57%) were on octreotide (Sandostatin LAR) and 83 (43%) on lanreotide (Somatuline Depot). The majority (>70%) of patients reported acromegaly symptoms despite treatment. A total of 52% of patients reported that their symptoms worsen towards the end of the dosing interval. Administration site pain lasting up to a week following injection was the most frequently reported injection-related symptom (70% of patients). Other injection site reactions included nodules (38%), swelling (28%), bruising (16%), scar tissue (8%) and inflammation (7%). Injection burden was similar between octreotide and lanreotide. Only a minority of patients received injections at home (17%) and 5% were self-injecting. Over a third of patients indicated a feeling of loss of independence due to the injections, and 16% reported repeated work loss days. Despite the physical, emotional and daily life impact of injections, patients were satisfied with their treatment, yet reported that modifications that would offer major improvement over current care would be ‘avoiding injections’ and ‘better symptom control’.

Conclusion

Lifelong injections of long-acting somatostatin analogues have significant burden on the functioning, well-being and daily lives of patients with acromegaly.

Free access

Markus Glaudo, Saskia Letz, Marcus Quinkler, Ulrich Bogner, Ulf Elbelt, Christian J Strasburger, Dirk Schnabel, Erwin Lankes, Sandra Scheel, Joachim Feldkamp, Christine Haag, Egbert Schulze, Karin Frank-Raue, Friedhelm Raue, Bernhard Mayr and Christof Schöfl

Background

Homozygous inactivating mutations of the calcium-sensing receptor (CaSR) lead to neonatal severe hyperparathyroidism (NSHPT), whereas heterozygous inactivating mutations result in familial hypocalciuric hypercalcemia (FHH). It is unknown why in some cases heterozygous CaSR mutations cause neonatal hyperparathyroidism (NHPT) clinically similar to NSHPT but with only moderately elevated serum calcium.

Methods

A literature survey was conducted to identify patients with heterozygous CaSR mutations and NHPT. The common NHPT CaSR mutants R185Q and R227L were compared with 15 mutants causing only FHH in the heterozygous state. We studied in vitro calcium signaling including the functional consequences of co-expression of mutant and wild-type (wt) CaSR, patients’ phenotype, age of disease manifestation and mode of inheritance.

Results

All inactivating CaSR mutants impaired calcium signaling of wt-CaSR regardless of the patients’ clinical phenotype. The absolute intracellular calcium signaling response to physiologic extracellular calcium concentrations in vitro showed a high correlation with patients’ serum calcium concentrations in vivo, which is similar in NHPT and FHH patients with the same genotype. Pedigrees of FHH families revealed that paternal inheritance per se does not necessarily lead to NHPT but may only cause FHH.

Conclusions

There is a significant correlation between in vitro functional impairment of the CaSR at physiologic calcium concentrations and the severity of alterations in calcium homeostasis in patients. Whether a particular genotype leads to NHPT or FHH appears to depend on additional predisposing genetic or environmental factors. An individual therapeutic approach appears to be warranted for NHPT patients.

Open access

Christian J Strasburger, Peter Vanuga, Juraj Payer, Marija Pfeifer, Vera Popovic, László Bajnok, Miklós Góth, Veˇra Olšovská, L‘udmila Trejbalová, Janos Vadasz, Eyal Fima, Ronit Koren, Leanne Amitzi, Martin Bidlingmaier, Oren Hershkovitz, Gili Hart and Beverly M K Biller

Objective

Growth hormone (GH) replacement therapy currently requires daily injections, which may cause distress and low compliance. C-terminal peptide (CTP)-modified growth hormone (MOD-4023) is being developed as a once-weekly dosing regimen in patients with GH deficiency (GHD). This study’s objective is to evaluate the safety, pharmacokinetics (PK), pharmacodynamics (PD) and efficacy of MOD-4023 administered once-weekly in GHD adults.

Design

54 adults with GHD currently treated with daily GH were normalized and randomized into 4 weekly dosing cohorts of MOD-4023 at 18.5%, 37%, 55.5% or 123.4% of individual cumulative weekly molar hGH dose. The study included 2 stages: Stage A assessed the effectiveness and PK/PD profiles of the 4 dosing regimens of MOD-4023. Stage B was an extension period of once-weekly MOD-4023 administration (61.7% molar hGH content) to collect further safety data and confirm the results from Stage A.

Results

Dose-dependent response was observed for both PK and PD data of weekly MOD-4023 treatment. Insulin-like growth factor I (IGF-I) SDS levels were maintained within normal range. The 18.5% cohort was discontinued due to low efficacy. MOD-4023 was well tolerated and exhibited favorable safety profile in all dose cohorts. The reported adverse events were consistent with known GH-related side effects.

Conclusions

Once-weekly MOD-4023 administration in GHD adults was found to be clinically effective while maintaining a favorable safety profile and may obviate the need for daily injections. Weekly GH injections may improve compliance and overall outcome. The promising results achieved in this Phase 2 study led to a pivotal Phase 3 trial, which is currently ongoing.

Free access

Michael Buchfelder, Aart-Jan van der Lely, Beverly M K Biller, Susan M Webb, Thierry Brue, Christian J Strasburger, Ezio Ghigo, Cecilia Camacho-Hubner, Kaijie Pan, Joanne Lavenberg, Peter Jönsson and Juliana H Hey-Hadavi

Objectives

ACROSTUDY is an international, non-interventional study of acromegaly patients treated with pegvisomant (PEGV), a growth hormone receptor antagonist and has been conducted since 2004 in 15 countries to study the long-term safety and efficacy of PEGV. This report comprises the second interim analysis of 2090 patients as of May 12, 2016.

Methods

Descriptive analyses of safety, pituitary imaging and outcomes on PEGV treatment up to 12 years were performed.

Results

Prior to starting PEGV, 96% of patients had reported surgery, radiation, medical therapy or any combinations of those. At start of PEGV, 89% of patients had IGFI levels above the upper limit of normal (ULN). The percentage of patients with normal IGFI levels increased from 53% at year 1 to 73% at year 10, and the average daily dose of PEGV increased from 12.8 mg (year 1) to 18.9 mg (year 10). A total of 4832 adverse events (AEs) were reported in 1137 patients (54.4%), of which 570 were considered treatment related in 337 patients (16.1%). Serious AEs were reported in 22% of patients, of which 2.3% were considered treatment related. Locally reported MRIs showed most patients (72.2%) had no change in tumor size relative to the prior scan; 16.8% had a decrease, 6.8% an increase and 4.3% both. In patients with normal liver tests at PEGV start, an ALT or AST elevation of >3× ULN at any time point during their follow-up was reported in 3%.

Conclusions

This second interim analysis confirms that long-term use of PEGV is an effective and safe treatment in patients with acromegaly.

Restricted access

Leonie H A Broersen, Femke M van Haalen, Tina Kienitz, Olaf M Dekkers, Christian J Strasburger, Alberto M Pereira and Nienke R Biermasz

Background

Adrenal crisis, the most feared complication of adrenal insufficiency, is a potentially life-threatening state of acute glucocorticoid deficiency. After successful surgery for Cushing’s syndrome, many patients develop (transient) adrenal insufficiency. The incidence of adrenal crisis in patients treated for hypercortisolism is unknown.

Methods

Cohort study included consecutive patients with Cushing’s syndrome with adrenal insufficiency after surgery from Leiden and Berlin from 2000 to 2015. We summarized the incidence of adrenal crisis, compared patients with and without adrenal crisis regarding potential risk factors for its occurrence and assessed the effect of better education in time on incidence of adrenal crisis.

Results

We included 106 patients, of whom 19 patients had a total of 41 adrenal crises. There were 9.0 crises per 100 patient-years at risk (95% confidence interval (CI): 6.7–12.0). All crises occurred while on hydrocortisone replacement. The risk ratio for a recurrent crisis was 2.3 (95% CI: 1.2–4.6). No clear change in incidence of adrenal crisis due to better education in time was observed. There was no difference in recurrence rate between patients with, and without any crisis, but patients with adrenal crisis had more often pituitary deficiencies.

Conclusions

The incidence of adrenal crises after treatment for Cushing’s syndrome is substantial, and patients who suffered from an adrenal crisis have higher risk for recurrent crisis. Adrenal crisis tends to present early after remission of Cushing’s syndrome, which is probably the period of severest HPA axis suppression, despite in general higher hydrocortisone replacement doses for withdrawal complaints in this period. Additional pituitary hormone deficiencies may be a risk marker for increased risk of adrenal crisis. However, further risk factor analysis is needed to identify risks for a first crisis. Effective education methods to prevent adrenal crises should be identified and implemented, including stress instructions by trained nursing staff before hospital discharge.

Free access

Elena Valassi, Alicia Santos, Maria Yaneva, Miklós Tóth, Christian J Strasburger, Philippe Chanson, John A H Wass, Olivier Chabre, Marija Pfeifer, Richard A Feelders, Stylianos Tsagarakis, Peter J Trainer, Holger Franz, Kathrin Zopf, Sabina Zacharieva, Steven W J Lamberts, Antoine Tabarin and Susan M Webb

Objective

The European Registry on Cushing's syndrome (ERCUSYN) is designed to collect prospective and follow-up data at EU level on Cushing's syndrome (CS).

Design and methods

Baseline data on 481 CS patients (390 females, 91 males; mean age (±s.d.): 44±14 years) collected from 36 centres in 23 countries, including new patients from 2008 and retrospective cases since 2000. Patients were divided into four major aetiologic groups: pituitary-dependent CS (PIT-CS) (66%), adrenal-dependent CS (ADR-CS) (27%), CS from an ectopic source (ECT-CS) (5%) and CS from other aetiologies (2%).

Results

Proportion of men in the ECT-CS group was higher than in the other groups (P<0.05). The ADR-CS group was older than the PIT-CS (P<0.05). Prevalence of hirsutism (92%) and diabetes (74%) in ECT-CS was higher than in the other groups (P<0.05 and P<0.01 respectively). PIT-CS had more skin alterations, menstrual irregularities and hirsutism than ADR-CS (P<0.01). Reduced libido was more prevalent in men than women (P<0.01). Prevalence of spine osteoporosis was higher in men than women (P<0.05), and males had more vertebral and rib fractures than females (52 vs 18% for vertebrae; P<0.001 and 34 vs 23% for ribs; P<0.05). ECT-CS consulted a diabetologist more frequently than ADR-CS (P<0.05), while a gynaecologist was consulted more often by women with PIT-CS or ADR-CS than with ECT-CS (P<0.05). Overall, weight gain was more common in women than men (P<0.01). CushingQoL and EuroQoL visual analogue scale scores did not differ between the groups.

Conclusions

The ERCUSYN project demonstrates a heterogeneous clinical presentation of CS at a European level, depending on gender and aetiology.

Free access

Elena Valassi, Holger Franz, Thierry Brue, Richard A Feelders, Romana Netea-Maier, Stylianos Tsagarakis, Susan M Webb, Maria Yaneva, Martin Reincke, Michael Droste, Irina Komerdus, Dominique Maiter, Darko Kastelan, Philippe Chanson, Marija Pfeifer, Christian J Strasburger, Miklós Tóth, Olivier Chabre, Antoine Tabarin, Michal Krsek, Carmen Fajardo, Marek Bolanowski, Alicia Santos, John A H Wass, Peter J Trainer and for the ERCUSYN Study Group

Objective

To evaluate which tests are performed to diagnose hypercortisolism in patients included in the European Registry on Cushing’s syndrome (ERCUSYN), and to examine if their use differs from the current guidelines.

Patients and methods

We analyzed data on the diagnostic tests performed in 1341 patients with Cushing’s syndrome (CS) who have been entered into the ERCUSYN database between January 1, 2000 and January 31, 2016 from 57 centers in 26 European countries. Sixty-seven percent had pituitary-dependent CS (PIT-CS), 24% had adrenal-dependent CS (ADR-CS), 6% had CS from an ectopic source (ECT-CS) and 3% were classified as having CS from other causes (OTH-CS).

Results

Of the first-line tests, urinary free cortisol (UFC) test was performed in 78% of patients, overnight 1 mg dexamethasone suppression test (DST) in 60% and late-night salivary cortisol (LSaC) in 25%. Use of LSaC increased in the last five years as compared with previous years (P < 0.01). Use of HDDST was slightly more frequent in the last 5 years as compared with previous years (P < 0.05). Of the additional tests, late-night serum cortisol (LSeC) was measured in 62% and 48-h 2 mg/day low-dose dexamethasone suppression test (LDDST) in 33% of cases. ACTH was performed in 78% of patients. LSeC and overnight 1 mg DST supported the diagnosis of both PIT-CS and ADR-CS more frequently than UFC (P < 0.05).

Conclusions

Use of diagnostic tests for CS varies across Europe and partly differs from the currently available guidelines. It would seem pertinent that a European consensus be established to determine the best diagnostic approach to CS, taking into account specific inter-country differences with regard to the availability of diagnostic tools.

Open access

Jens Sandahl Christiansen, Philippe F Backeljauw, Martin Bidlingmaier, Beverly M K Biller, Margaret C S Boguszewski, Felipe F Casanueva, Philippe Chanson, Pierre Chatelain, Catherine S Choong, David R Clemmons, Laurie E Cohen, Pinchas Cohen, Jan Frystyk, Adda Grimberg, Yukihiro Hasegawa, Morey W Haymond, Ken Ho, Andrew R Hoffman, Jeff M P Holly, Reiko Horikawa, Charlotte Höybye, Jens Otto L Jorgensen, Gudmundur Johannsson, Anders Juul, Laurence Katznelson, John J Kopchick, K O Lee, Kuk-Wha Lee, Xiaoping Luo, Shlomo Melmed, Bradley S Miller, Madhusmita Misra, Vera Popovic, Ron G Rosenfeld, Judith Ross, Richard J Ross, Paul Saenger, Christian J Strasburger, Michael O Thorner, Haim Werner and Kevin Yuen

Objective

The Growth Hormone (GH) Research Society (GRS) convened a workshop to address important issues regarding trial design, efficacy, and safety of long-acting growth hormone preparations (LAGH).

Participants

A closed meeting of 55 international scientists with expertise in GH, including pediatric and adult endocrinologists, basic scientists, regulatory scientists, and participants from the pharmaceutical industry.

Evidence

Current literature was reviewed for gaps in knowledge. Expert opinion was used to suggest studies required to address potential safety and efficacy issues.

Consensus process

Following plenary presentations summarizing the literature, breakout groups discussed questions framed by the planning committee. Attendees reconvened after each breakout session to share group reports. A writing team compiled the breakout session reports into a draft document that was discussed and revised in an open forum on the concluding day. This was edited further and then circulated to attendees from academic institutions for review after the meeting. Participants from pharmaceutical companies did not participate in the planning, writing, or in the discussions and text revision on the final day of the workshop. Scientists from industry and regulatory agencies reviewed the manuscript to identify any factual errors.

Conclusions

LAGH compounds may represent an advance over daily GH injections because of increased convenience and differing phamacodynamic properties, providing the potential for improved adherence and outcomes. Better methods to assess adherence must be developed and validated. Long-term surveillance registries that include assessment of efficacy, cost-benefit, disease burden, quality of life, and safety are essential for understanding the impact of sustained exposure to LAGH preparations.