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Dive into the research topics where Stephan Klauke is active.

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Featured researches published by Stephan Klauke.


AIDS | 2001

Durability of HIV-1 viral suppression over 3.3 years with multi-drug antiretroviral therapy in previously drug-naive individuals

Andrew N. Phillips; Veronica Miller; Caroline Sabin; Alessandro Cozzi Lepri; Stephan Klauke; Markus Bickel; Hans Wilhelm Doerr; Andrew Hill; Schlomo Staszewski

BackgroundRelatively little is known about the long-term durability of viral suppression in individuals initially achieving a viral load of less than 50 copies/ml within 24 weeks of starting antiretroviral therapy, nor the extent to which therapy interruption accounts for the loss of suppression. MethodsWe intensely followed all 336 antiretroviral-naive patients attending the Goethe Universitat Clinic who began multi-drug combination regimens and in whom a viral load of less than 50 copies/ml was achieved within 24 weeks, in order to assess the risk of viral load rebound. Inspection of case notes allowed the distinction of viral rebound according to whether there was an associated complete interruption of therapy. ResultsA total of 61 patients experienced viral rebound during 543.1 person-years of follow-up, giving a 25.3% risk of rebound by 3.3 years from first achieving viral suppression. However, for 47 of the patients with viral rebound there was an associated documented complete interruption of antiretroviral therapy, mostly as a result of co-morbidities, leaving 14 who appear to represent a failure of the virological efficacy of therapy (viral breakthrough; 5.2% risk by 3.3 years). The risk of viral breakthrough declined with the increased duration of suppression (P = 0.01). ConclusionThe intrinsic virological effectiveness of multi-drug antiretroviral therapy in previously drug-naive individuals appears to be such that viral suppression, once achieved, can be maintained for several years in patients not interrupting therapy. The major challenge is to develop regimens that can be taken consistently and safely for such long periods of time.


AIDS | 2004

Saquinavir drug exposure is not impaired by the boosted double protease inhibitor combination of lopinavir/ ritonavir

Christoph Stephan; Nils von Hentig; Irene Kourbeti; Brenda Dauer; Manfred Mösch; Thomas Lutz; Stephan Klauke; Sebastian Harder; Michael Kurowski; Schlomo Staszewski

Objective: To assess the pharmacokinetic interaction of saquinavir and lopinavir/ritonavir. Design: Patients from the Frankfurt HIV cohort with limited reverse transcriptase inhibitor (RTI) options received the protease inhibitor (PI) combination of saquinavir (soft-gel capsules, 1000 mg twice a day) plus lopinavir/ritonavir (400/100 mg twice a day), without RTI (LOPSAQ group). A control group received the same doses of saquinavir and ritonavir plus two to three RTI (RITSAQ group). A steady-state 12 h pharmacokinetic assessment was performed. Methods: Plasma levels of saquinavir, ritonavir and lopinavir were determined by liquid chromatography–tandem mass spectrophotometry. Minimum and maximum plasma concentrations (Cmin and Cmax), the clearance (Cltot) and the area under the concentration time curve (AUC) were calculated. Results: Data were collected from 45 patients (LOPSAQ) and 32 patients (RITSAQ). There was no significant difference between the groups for median saquinavir Cmin, Cmax, Cltot and AUC (LOPSAQ: 543 ng/ml, 2300 ng/ml, 1020 ml/min and 16 977 ng*h/ml; RITSAQ: 427 ng/ml, 2410 ng/ml, 1105 ml/min and 15 130 ng*h/ml). Median ritonavir Cmin, Cmax and AUC were lower, the Cltot was higher in the LOPSAQ group (78 ng/ml, 428 ng/ml and 2972 ng*h/ml, 551 ml/min) compared with RITSAQ (194 ng/ml, 683 ng/ml and 6506 ng*h/ml, 266 ml/min; P < 0.001). Lopinavir levels were similar to historical data. Conclusion: Effective plasma levels of both saquinavir and lopinavir can be achieved by the co-administration of saquinavir soft-gel capsules and lopinavir/ritonavir. This boosted double PI combination could be an effective option for patients with limited RTI options.


The Journal of Infectious Diseases | 2002

Human Immunodeficiency Virus Rebound after Suppression to <400 Copies/mL during Initial Highly Active Antiretroviral Therapy Regimens, according to Prior Nucleoside Experience and Duration of Suppression

Andrew N. Phillips; Schlomo Staszewski; Fiona Lampe; Michael Youle; Stephan Klauke; Markus Bickel; Caroline Sabin; Hans Wilhelm Doerr; Margaret Johnson; Clive Loveday; Veronica Miller

This study evaluated 1433 human immunodeficiency virus (HIV)-infected patients starting highly active antiretroviral therapy (HAART), 409 (28%) of whom had prior nucleoside experience and achieved an HIV load of <400 copies/mL by 24 weeks of therapy. Three hundred seven patients experienced virus rebound during a total of 2773.3 person-years of follow-up. There was a higher rate of virus rebound among the patients with pre-HAART nucleoside experience (relative hazard [RH], 2.86; 95% confidence interval, 2.22-3.84; P<.0001) and a decreasing rate of virus rebound with increasing duration of virus suppression (i.e., time since achieving a virus load of <400 HIV RNA copies/mL) among both the nucleoside-experienced and naive patients (P<.0001), but the difference between the groups persisted into the third year of follow-up (P=.0007). Even patients who had experienced <2 months of nucleoside therapy before beginning HAART had an increased risk of virus rebound (RH, 1.95; P=.009). It appears that only a small period of pre-HAART nucleoside therapy is sufficient to confer a disadvantage, in terms of risk of virus rebound, that persists for several years.


Antimicrobial Agents and Chemotherapy | 2007

Pharmacokinetics of Saquinavir, Atazanavir, and Ritonavir in a Twice-Daily Boosted Double-Protease Inhibitor Regimen

Nils von Hentig; Axel Müller; Carsten Rottmann; Timo Wolf; Thomas Lutz; Stephan Klauke; Michael Kurowski; Bruno G. Oertel; Brenda Dauer; Sebastian Harder; Schlomo Staszewski

ABSTRACT The objective of this study was to evaluate the pharmacokinetics of atazanavir (ATV), saquinavir (SQV), and ritonavir (RTV) in a boosted double-protease inhibitor (PI) therapy regimen without reverse transcriptase inhibitors (RTIs). The study design was as follows. Patients with limited RTI options received a PI combination of 300/100 mg ATV/RTV once daily and 1,000 mg SQV twice daily (group 1; n = 49) without RTI comedication. The results were compared to the plasma concentrations of PIs of patients taking either 300 mg ATV/100 mg RTV once daily plus RTIs (group 2; n = 72) or patients taking 1,000 mg SQV/100 mg RTV plus RTIs (group 3; n = 90). The study methods were as follows. Patients were given a 12/24-h pharmacokinetic assessment at steady state. Drug concentrations were measured by liquid chromatography-tandem mass spectrometry. The minimum and maximum concentrations (Cmin and Cmax), area under the concentration-time curve under steady-state conditions (AUCss), elimination half-life, time of maximum concentration and lag time were subject to statistical analysis. The results show that patients treated with ATV/SQV/RTV exhibited significantly high SQV concentrations and moderate enhancement of the AUCss of ATV in comparison to those of patients of the control groups: for SQV in groups 1 and 3, the geometric mean (GM) of the AUCss was 22,794 versus 15,759 ng·h/ml (GM ratio [GMR] = 1.45; P < 0.05), the GM of the Cmax was 3,257 versus 2,331 ng/ml (GMR = 1.40; P < 0.05), and the GM of the Cmin was 438 versus 437 ng/ml (GMR = 1.00); for ATV in groups 1 and 2, the GM of the AUCss was 39,154 versus 33,626 ng·h/ml (GMR = 1.16), the GM of the Cmax was 3,488 versus 2,924 ng/ml (GMR = 1.20), and the GM of the Cmin was 515 versus 428 ng/ml (GMR = 1.21). RTV levels were comparable for all groups. A subgroup analysis detected only marginal differences in ATV plasma exposure if combined with tenofovir-disoproxilfumarate and without it. We conclude that our pharmacokinetic results support the use of a boosted double-PI regimen of ATV/SQV/RTV as a treatment option for patients who need antiretroviral therapy without RTIs.


Diseases of The Colon & Rectum | 2014

Long-term effects of chemoradiotherapy for anal cancer in patients with HIV infection: oncological outcomes, immunological status, and the clinical course of the HIV disease.

Ingeborg Fraunholz; Annette Haberl; Stephan Klauke; Peter Gute; Claus Rödel

BACKGROUND: Despite the increasing evidence for chemoradiotherapy as standard treatment for anal cancer in patients with HIV infection, there is still some uncertainty regarding increased toxicity and adverse effects on the immune status. OBJECTIVE: We report the clinical outcome of 5-fluorouracil/mitomycin C-based concurrent chemoradiotherapy for anal carcinoma in patients with HIV infection with an emphasis on the long-term course of CD4 counts and the HIV-related morbidity during follow-up. DESIGN AND SETTINGS: A retrospective single-institution chart review was performed. PATIENTS: Between 1997 and 2012, 36 HIV-positive patients were treated with standard chemoradiotherapy (median tumor dose, 54 (range, 50.4–60.4) Gy at 1.8 Gy/fraction; 5-fluorouracil, 800–1000 mg/m2, days 1–4 or 1–5; mitomycin C, 10 mg/m2, day 1, in the first and fifth week). MAIN OUTCOME MEASURES: A retrospective analysis was performed with respect to tumor response, local control, cancer and overall survival, and toxicity. Immunological parameters, including pre- and posttreatment CD4 counts, viral load, and HIV-specific morbidity were recorded during follow-up. RESULTS: Chemoradiotherapy could be completed in all patients. Acute grade 3 toxicities occurred in 17/36 patients (47%). Complete response was achieved in 31 patients (86%). Five-year local control, colostomy-free, cancer-specific, and overall survival were 72%, 87%, 77%, and 74%. The median pretreatment CD4 count significantly decreased from 367 cells/&mgr;L to 139 cells/&mgr;L, 3 to 7 weeks after completion of chemoradiotherapy (p < 0.001). Four patients (11%) experienced opportunistic illnesses during the follow-up (median, 66; range, 10–164 months). LIMITATIONS: This study is limited by its retrospective design and its small sample size. CONCLUSIONS: Our data confirm again that, in the highly active antiretroviral therapy era, anal cancer can be treated in HIV-positive patients with standard chemoradiotherapy, with a clinical outcome similar to their HIV-negative counterparts. The chemoradiotherapy-related decline of the CD4 counts, which remain decreased up to 6 years after chemoradiotherapy, was not associated with increased HIV-related clinical morbidity.


Current HIV Research | 2009

Quadruple Nucleos(t)ide Reverse Transcriptase Inhibitors-Only Regimen of Tenofovir Plus Zidovudine/Lamivudine/Abacavir in Heavily Pre-Treated HIV-1 Infected Patients: Salvage Therapy or Backbone Only?

Christoph Stephan; Brenda Dauer; Pavel Khaykin; Martin Stuermer; Peter Gute; Stephan Klauke; Schlomo Staszewski

BACKGROUND We investigated the virologic and immunologic responses to a mono-class, nucleoside/nucleotide reverse transcriptase inhibitor - combination therapy consisting of tenofovir and zidovudine/lamivudine/abacavir in therapy experienced patients. METHODS Retrospective study of 122 patients. Primary analysis was performed at 48 weeks. Virologic response was defined as viral load levels less than 400 copies/ml. RESULTS About half of the patients had switched to tenofovir+ zidovudine/lamivudine/abacavir for simplification purposes or toxicity while the other half had experienced virologic failure. 80/122 (66%) responded. Median viral load decreased to 78 copies/ml at week 48; median CD4 count increased to 321 cells/mm(3). Of the 42 virologic failures, only 3 patients failed after week 24. 24/35 patients who had been on a non-suppressive zidovudine/lamivudine/abacavir-only regimen at baseline and added tenofovir to intensify, responded. 41/53 patients who switched from any nucleoside reverse transcriptase inhibitor-only regimen improved or maintained suppression. Genotypes were available for 85/122 patients. The only predictor of virologic failure was the combination 41L+210W+215Y/F mutational pattern. 16 of the patients who failed on tenofovir+ zidovudine/lamivudine/abacavir therapy selected new primary nucleoside reverse transcriptase inhibitor resistance mutations that they previously did not have. 48/85 (56%) patients with genotype tests had at least 3 (3-10; median 4) nucleoside reverse transcriptase inhibitor resistance-associated mutations in the past. CONCLUSIONS Patients heavily pre-treated with nucleoside analogues may show response to mono-class tenofovir+ zidovudine/lamivudine/abacavir therapy despite having a history of failure with nucleoside reverse transcriptase inhibitors. Lower baseline viral load, higher baseline CD4 count were significant predictors for response. Archived 41L+210W+215Y/F mutational pattern was significantly associated with non-response.


International Journal of Std & Aids | 2005

Use of bioelectrical impedance analysis to determine body composition changes in HIV-associated wasting

Stephan Klauke; Harald Fischer; Armin Rieger; Lukas Frühauf; Schlomo Staszewski; Peter-Henning Althoff; Eilke B. Helm

AIDS wasting syndrome results in loss of lean body mass and body cell mass. This 12-week, open-label study used bioelectrical impedance analysis to measure body composition changes in 24 patients with AIDS wasting syndrome receiving recombinant human growth hormone (r-hGH). The primary endpoint was percentage monthly change in body weight before/after r-hGH. Secondary endpoints included change from baseline in body composition (bioelectrical impedance analysis), isometric strength and CD4+count. Twenty patients completed the study: r-hGH resulted in mean weight gains (+2.7%, P=0.146), and significant increases in mean body cell mass (+8.0%, P=0.0211), lean body mass (+4.8%, P=0.0373) and water (+5.5%, P<0.023). Body fat decreased throughout, but not significantly. r-hGH was generally well tolerated; the most frequent adverse events were fever (7.3%) and diarrhoea (6.3%). Thus, bioelectrical impedance analysis can detect improved body cell mass independent of changes in body weight resulting from r-hGH treatment in patients with AIDS wasting syndrome.


Journal of Antimicrobial Chemotherapy | 2009

Once-daily treatment with saquinavir mesylate (2000 mg) and ritonavir (100 mg) together with a fixed-dose combination of abacavir/lamivudine (600/300 mg) or tenofovir/emtricitabine (245/200 mg) in HIV-1-infected patients

Markus Bickel; A. Bodtländer; Gaby Knecht; Christoph Stephan; N. von Hentig; Michael Kurowski; Peter Gute; Stephan Klauke; Thomas Lutz

OBJECTIVES To investigate the feasibility and pharmacokinetics of a once-daily regimen of 2000 mg saquinavir mesylate boosted with 100 mg ritonavir. PATIENTS AND METHODS Patients successfully treated with 1000 mg saquinavir boosted with 100 mg ritonavir twice daily together with two nucleoside or nucleotide reverse transcriptase inhibitors [N(t)RTIs] who were switched to 2000 mg saquinavir with 100 mg ritonavir once daily with unchanged N(t)RTI therapy were analysed. CD4 cells, HIV-RNA PCR and metabolic parameters were compared between baseline and 3, 6, 9 and 12 months after the switch. Saquinavir and ritonavir drug levels were measured before and a median of 3 weeks after switching from twice to once daily at 0, 1, 2, 4, 6, 9, 12 and 24 h after intake of the medication. The area under the serum concentration-time curve from 0 to 24 h (AUC(0-24)) was calculated using the trapezoidal rule. RESULTS Eighteen patients (16 males, median age of 41 years) with a median CD4 cell count of 464 cells/mm(3) were analysed. HIV-RNA PCR remained <500 copies/mL for all patients. After switching from 100 mg twice daily to 100 mg once daily, the AUC(0-24) for ritonavir decreased significantly [21 874 to 10 267 ng.h/mL, geometric mean ratio (GMR) = 0.47; P < 0.001], whereas the AUC(0-24) for saquinavir decreased only marginally from 35 000 to 34 490 ng.h/mL (GMR = 0.99; P = 0.426). The CD4 cell count and the fasting metabolic parameters remained unchanged. CONCLUSIONS Once-daily treatment with ritonavir-boosted saquinavir was well tolerated and resulted in similar saquinavir drug exposure despite much lower ritonavir concentrations when compared with a twice-daily dosing schedule.


Scandinavian Journal of Infectious Diseases | 2008

Long-term effect on body composition and metabolic parameters after treatment with recombinant human growth hormone (r-hGH) in HIV-1 infected patients with lipodystrophy

Markus Bickel; Stephan Zangos; Thomas Lutz; Johannes Eisen; Gabi Knecht; Frank D. Goebel; Catherine M. Crespi; Volkmar Jacobi; Schlomo Staszewski; Stephan Klauke

Several studies have shown reduction of visceral adipose tissue (VAT) using recombinant human growth hormone (r-hGH) in HIV-1+ patients, but whether these effects are maintained after the end of treatment is unknown. In a prospective, randomized study we previously studied the effects of r-hGH 4 mg daily vs 3 times/week over 12 weeks, followed by a 2 mg daily maintenance dose for an additional 12 weeks. T1 weighted MRI flash sequences were performed of the face, abdomen and at mid-thigh level (MTF) at baseline, week 12, week 24 and at follow-up.Of 20 subjects who completed the 24-week study, follow-up is available for 16 patients (15 male, mean age 44.8 y, mean duration of HIV infection 13.5 y). After a median time of follow-up of 9 months, VAT remained overall 18% below baseline level (p =0.005). MTF was significantly reduced by 12% compared to its baseline level (p =0.03). Fasting glucose levels significantly improved by 21% compared to baseline (p =0.006). These results suggest that the achieved reduction of VAT using r-hGH in lipodystrophic HIV+ patients is in part maintained after a median follow-up of 9 months.


Journal of the International AIDS Society | 2008

Virological and immunological response to three boosted protease inhibitor regimens

C Baumgardt; Christoph Stephan; Annette Haberl; Hans-Reinhard Brodt; M Stuermer; Stephan Klauke; Peter Gute; Markus Bickel; Pavel Khaykin; N von Hentig; Schlomo Staszewski

Poster presentation: Purpose of the study To compare the virological, immunological and clinical response to three boosted double protease inhibitor (PI) regimens of saquinavir and ritonavir in combination with lopinavir (LOPSAQ), atazanavir (ATSAQ) or fosamprenavir (FOSAQ) without reverse transcriptase inhibitors (RTI) in HIV-positive patients with limited RTI treatment options. ...

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Schlomo Staszewski

Goethe University Frankfurt

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Markus Bickel

Goethe University Frankfurt

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Peter Gute

Goethe University Frankfurt

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Christoph Stephan

Goethe University Frankfurt

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Annette Haberl

Goethe University Frankfurt

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Brenda Dauer

Goethe University Frankfurt

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Sebastian Harder

Goethe University Frankfurt

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Nils von Hentig

Goethe University Frankfurt

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