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Dive into the research topics where Christian Zurth is active.

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Featured researches published by Christian Zurth.


The Journal of Clinical Pharmacology | 2012

Ovulation‐Inhibiting Effects of Dienogest in a Randomized, Dose‐Controlled Pharmacodynamic Trial of Healthy Women

Christine Klipping; Ingrid Duijkers; Ageeth Remmers; Thomas Faustmann; Christian Zurth; Stefan Klein; Barbara Schuett

Dienogest offers pharmacological advantages for the effective treatment of endometriosis and for use in contraception and hormone replacement therapy. This pharmacodynamic study investigated the ovulation‐inhibiting effects of dienogest monotherapy in healthy women. Dienogest was administered at 0.5, 1, 2, or 3 mg daily for up to 72 days to women aged 18 to 35 years (n = 102). Ovarian activity was assessed pretreatment and during 2 treatment periods (days 0–36 and days 37–72) by the Hoogland score, based on follicle size and serum estradiol and progesterone levels. Additional hormonal parameters and endometrial thickness were assessed. Hoogland scoring indicated ovulation in all women pretreatment, decreasing to 3 of 21, 1 of 23, 0 of 20, and 0 of 23 women in the 0.5‐, 1‐, 2‐, and 3‐mg groups, respectively (per‐protocol set). Maximum serum estradiol concentrations were similar to pretreatment levels in the 0.5‐ or 1‐mg group and decreased moderately (within physiologic levels) in the 2‐ or 3‐mg group. Endometrial thickness was reduced by all dienogest doses. Hormonal changes during follow‐up indicated resumption of ovulation in most women, shortly after treatment cessation. Dienogest ≥2 mg daily provides moderate suppression of estradiol production and reliable ovulation inhibition, which reverses rapidly after treatment cessation.


Fertility and Sterility | 2014

Pharmacokinetics of two low-dose levonorgestrel-releasing intrauterine systems and effects on ovulation rate and cervical function: pooled analyses of phase II and III studies

Dan Apter; Kristina Gemzell-Danielsson; Brian Hauck; K. Rosen; Christian Zurth

OBJECTIVE To assess the pharmacokinetics and pharmacodynamics of levonorgestrel intrauterine system (LNG-IUS) 13.5 mg and LNG-IUS 19.5 mg (total content). DESIGN Pooled pharmacokinetic and pharmacodynamic analyses of phase II and III studies. SETTING Randomized, open-label, multicenter studies. PATIENT(S) Nulliparous and parous women. INTERVENTION(S) Levonorgestrel intrauterine system 13.5 mg, LNG-IUS 19.5 mg, or LNG-IUS 20 μg/24 h (total content 52 mg). MAIN OUTCOME MEASURE(S) Pharmacokinetics of LNG, ovulation rate, cervical function, and endometrium effects. RESULT(S) The in vivo LNG release rate of LNG-IUS 13.5 mg was approximately 14 μg/24 h after 24 days, declining progressively to 5 μg/24 h after 3 years. The average LNG serum concentration over 3 years of use was 74.3 ng/L, 114 ng/L, and 218 ng/L for LNG-IUS 13.5 mg, LNG-IUS 19.5 mg, and LNG-IUS 20 μg/24 h, respectively. All treatments showed very similar progestogenic effects on cervical mucus, with low and similar cervical scores throughout treatment. Ovulation was observed in the majority of women in all groups where assessment was possible, although there was a lower incidence of anovulation with LNG-IUS 13.5 mg and LNG-IUS 19.5 mg compared with LNG-IUS 20 μg/24 h. The progestogenic effect on the endometrium was marked in all three LNG-IUS groups. CONCLUSION(S) Levonorgestrel intrauterine system 13.5 mg and LNG-IUS 19.5 mg result in alower systemic exposure to LNG, lower incidence of anovulation, and similar progestin impact on the endometrium and cervical function compared with LNG-IUS 20 μg/24 h.


principles and practice of constraint programming | 2014

Pharmacokinetic overview of ethinyl estradiol dose and bioavailability using two transdermal contraceptive systems and a standard combined oral contraceptive

Birte Hofmann; Isabel Reinecke; Barbara Schuett; Martin Merz; Christian Zurth

Objective: To determine the relative bioavailability of ethinyl estradiol (EE) and gestodene (GSD) after application of a novel transdermal contraceptive patch vs. a standard combined oral contraceptive (COC) pill (study 1), and to evaluate the pharmacokinetics (PK) of EE after application of the EE/GSD patch compared with an EE/norelgestromin (NGMN) patch (study 2). Materials: Participants were healthy, non-obese women aged 18 – 45 years (study 1) or 18 – 35 years (study 2). Compositions of study treatments were as follows: 0.55 mg EE/2.1 mg GSD (EE/GSD patch); 0.02 mg EE/0.075 mg GSD (standard COC); 0.6 mg EE/6 mg NGMN (EE/NGMN patch). Methods: In study 1, which consisted of 3 treatment periods (each followed by 7 patch- or pill-free days), treatments were administered in one of two randomized orders: either P–M–E (EE/GSD patch (P) every 7 days for 28 days → COC (M) once-daily for 21 days → two 7-day patch-wearing periods followed by one 10-day patch-wearing phase (E)), or the same treatments administered in sequence M–P–E. For study 2, participants received either the EE/GSD patch or EE/NGMN patch for seven treatment cycles (one patch per week for 3 weeks followed by a 7-day patch-free interval). Results: In study 1, average daily exposure to EE was similar for treatments P and M; the mean daily area under the concentration-time curve (AUC) ratio of treatment P vs. treatment M for EE was 1.06 (90% confidence interval (CI): 0.964 – 1.16), indicating average daily delivery similar to oral administration of 0.019 – 0.023 mg EE. For unbound GSD, average daily exposure was lower for treatment P vs. treatment M. The mean AUC ratio of treatment P vs. treatment M for unbound GSD was 0.820 (90% CI: 0.760 – 0.885), indicating average daily delivery from the patch of 0.057 – 0.066 mg GSD. Prolonged patch wearing did not result in a distinct decline in GSD and EE serum concentrations. In study 2, AUC at steady state (AUC0–168,ss), average steady-state serum concentration, and maximum steady-state serum concentration for EE was 2.0 – 2.7-fold higher for the EE/NGMN patch vs. the EE/GSD patch. The EE/GSD patch was well tolerated in both studies. Conclusions: Based on the 90% CI of the AUC ratio of oral treatment vs. patch application for unbound GSD and EE, the daily doses of GSD and EE released from the EE/GSD patch over the 7-day application period provided the same systemic exposure as those recorded after daily oral administration of a COC containing 0.02 mg EE and 0.06 mg GSD. The EE/GSD patch showed reduced EE exposure compared with the EE/NGMN patch. Together with its good tolerability, these properties support the EE/GSD patch as an effective and well-tolerated alternative to available transdermal and oral contraceptives.


principles and practice of constraint programming | 2014

Implications of different application sites on the bioavailability of a transdermal contraceptive patch containing ethinyl estradiol and gestodene: an open-label, randomized, crossover study.

Joachim Höchel; Barbara Schuett; Matthias Ludwig; Christian Zurth

OBJECTIVES A novel once-a-week contraceptive patch delivers the same systemic exposure seen with a combined oral contraceptive pill containing 0.02 mg ethinyl estradiol (EE) and 0.06 mg gestodene (GSD). This study evaluated the relative bioavailability of EE and GSD after application of this patch to three different sites. METHODS In this phase I, open-label, randomized, intra-individual comparison, crossover study, 43 women (aged 18 - 45 years) were randomized to one of six treatment sequences. Patches were applied to two test sites (buttocks and outer, upper arm) and one comparator site (lower abdomen). In each treatment period, four patches were worn for 7 days each, followed by a 7-day, patch-free interval. The primary objective was to investigate the relative bioavailability of transdermally administered EE and GSD between test and comparator sites using the primary variable area under the concentration- time curve (AUC(0-168)) during week 4 of each period. RESULTS Of the 43 women who were randomized, 43 were included in the set for safety evaluation and 40 were included in the set for pharmacokinetic (PK) analysis. Three subjects were excluded from the PK analysis as they failed to complete the study. AUC(0-168) for EE and GSD were equal when the patch was applied to buttocks or abdomen (AUC(0-168) ratios: EE, 1.07 (94% confidence interval, CI: 0.994 - 1.16); GSD, 1.02 (94% CI: 0.946 - 1.10)). Relative bioavailabilities for EE and GSD were 31% and 24% higher, respectively, for arm vs. abdomen. AUC(0-168) 94% CI for the arm/abdomen ratio exceeded the pre-defined bioequivalence range of 80 - 125% (EE: 1.21 - 1.42; GSD: 1.15 - 1.34). Other PK parameters were correspondingly higher for arm vs. buttocks or abdomen. Patch adhesion and tolerability were good, with no relevant differences between sites. CONCLUSION Differences in systemic EE/GSD exposure following patch application to the outer, upper arm vs. lower abdomen and buttocks are unlikely to be clinically relevant, and there were no relevant safety concerns.


Journal of Obstetrics and Gynaecology | 2016

A two-centre, open-label, randomised study of ovulation inhibition with three transdermal contraceptive patches, each containing different amounts of ethinyl estradiol and gestodene in healthy, young women.

K. Waellnitz; I. Duijkers; C. Klipping; T. Rautenberg; B. Rohde; Christian Zurth

Here we report the findings of a two-centre, open-label, randomised, Phase IIa study designed to investigate whether an ethinyl estradiol (EE)/gestodene (GSD) patch that has been developed (referred to herein as the ‘EE/GSD patch’) reliably inhibits ovulation in comparison with patches delivering lower doses of these hormones. The study rationale was to provide justification of the doses of EE and GSD selected for the EE/GSD patch. Healthy women, aged 18–35 years, were randomised to receive treatment with either the EE/GSD patch, a ‘reduced-GSD patch’ (delivering similar amounts of EE and approximately half the amount of GSD) or a ‘reduced-EE/GSD patch’ (delivering half the amount of EE and GSD). Treatment was administered for three 28-day cycles (three × 7 patch-wearing days, plus a 7-day patch-free interval). The primary pharmacodynamic variable was the percentage of women with ovulation in at least one of Cycles 2 and/or 3, as indicated by Hoogland score. Pharmacokinetic parameters for EE and GSD were also measured. Results indicated that the EE/GSD patch effectively suppressed ovulation, while patches delivering lower doses of EE and GSD were less effective for this purpose. All three patches showed comparable tolerability.


Clinical pharmacology in drug development | 2015

Pharmacokinetics and adhesion of a transdermal patch containing ethinyl estradiol and gestodene under conditions of heat, humidity, and exercise: A single‐center, open‐label, randomized, crossover study

Christian Zurth; Barbara Schuett; Manuela Casjens; Matthias Ludwig; Katrin Waellnitz

In this open‐label, randomized study, 36 women (18−45 years) applied an ethinyl estradiol/gestodene contraceptive patch once‐weekly for 3 weeks followed by a 1‐week, patch‐free interval, in 3 treatment periods. The primary objective was to evaluate the pharmacokinetics of ethinyl estradiol and gestodene under conditions of heat, humidity, and exercise. The secondary objective was to evaluate patch adhesion under the same conditions. Weeks 1 and 2 of each period comprised “standardized normal activity” (SNA); in week 3, SNA continued or women used a sauna, whirlpool, swimming pool, or performed an exercise combination. Thirty‐one women completed the study; 23 yielded evaluable pharmacokinetic data. Analyses were exploratory and conducted using an analysis of variance. Area under the concentration–time curve from 0 to 168 hours (AUC0−168) for gestodene and ethinyl estradiol during sauna, swimming, and whirlpool was equivalent to previous SNA recordings. For exercise combination, the gestodene AUC0−168 was 12% lower compared with SNA, albeit not considered clinically relevant. Two women lost a total of 3 patches during sporting activities; other detachments during this week were not correlated with sporting activity.


The Journal of Clinical Pharmacology | 2014

Pharmacokinetics of continuous once‐a‐week combination 17β‐Estradiol/Low‐ or high‐dose levonorgestrel transdermal delivery systems in postmenopausal women

Adel H. Karara; Lester I. Harrison; Armen P. Melikian; Nagaraju Poola; Dennis Morrison; Dale Bourg; Linda Bourg; Christian Zurth

Two open‐label, randomized, two‐period, crossover studies were performed to determine the safety, delivery rates, and pharmacokinetic properties of a combination estradiol (E2)/levonorgestrel (LNG) transdermal delivery system (TDS). Study 1 enrolled 24 postmenopausal women who received a single TDS containing 4.4 mg E2 and 1.39 mg of LNG (E2/LNG Low) or E2 0.050 mg/24 hours TDS and 0.090 mg LNG oral tablet. Study 2 enrolled 44 postmenopausal women who received either E2/LNG Low or TDS containing 4.4 mg E2 and 2.75 mg LNG (E2/LNG High) weekly for a period of 4 weeks. E2, estrone (E1), LNG, and sex hormone‐binding globulin (SHBG) serum concentrations were determined. Overall, both E2/LNG TDS were well tolerated and had excellent adhesion properties. The average daily delivery for E2/LNG Low was 0.045 mg for E2 and 0.0132 mg for LNG. Following weekly delivery of E2/LNG Low or High for 4 weeks, the combination of E2 with two different strengths of LNG did not alter the pharmacokinetic profile of E2. SHBG, total cholesterol, and triglycerides concentrations significantly decreased compared to baseline. Both E2/LNG Low and High TDSs were well tolerated and provided continuous drug delivery over 7 days supporting the benefits of the transdermal route of administration in optimally delivering hormonal therapy.


Annals of Nuclear Medicine | 2016

Pharmacokinetics of single dose radium-223 dichloride (BAY 88-8223) in Japanese patients with castration-resistant prostate cancer and bone metastases

Keisuke Yoshida; Tomohiro Kaneta; Shoko Takano; Madoka Sugiura; Tsuyoshi Kawano; Ayako Hino; Tou Yamamoto; Kazuya Shizukuishi; Masato Kaneko; Christian Zurth; Tomio Inoue


Archive | 2005

Oral solid dosage forms containing a low dose of estradiol

Kristina Mueller; Torsten Wagner; Adrian Funke; Christian Zurth


Archive | 2009

ESTRADIOL-CONTAINING DRUG DELIVERY SYSTEM

Adrian Funke; Sascha General; Ildiko Terebesi; Christian Zurth; Sofia Alincic-kunz; Matthias Schäfer; Thomas Holler; Konstanze Diefenbach

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Barbara Schuett

Bayer HealthCare Pharmaceuticals

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Adrian Funke

Bayer HealthCare Pharmaceuticals

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Ildiko Terebesi

Bayer HealthCare Pharmaceuticals

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Matthias Ludwig

Bayer HealthCare Pharmaceuticals

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K. Rosen

Bayer HealthCare Pharmaceuticals

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Dan Apter

University of Helsinki

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Adel H. Karara

Bayer HealthCare Pharmaceuticals

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