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  • 1
    Online Resource
    Online Resource
    Proceedings of the National Academy of Sciences ; 2011
    In:  Proceedings of the National Academy of Sciences Vol. 108, No. 42 ( 2011-10-18), p. 17474-17479
    In: Proceedings of the National Academy of Sciences, Proceedings of the National Academy of Sciences, Vol. 108, No. 42 ( 2011-10-18), p. 17474-17479
    Abstract: The worldwide spread of antibiotic-resistant bacteria has lent urgency to the search for antibiotics with new modes of action that are devoid of preexisting cross-resistances. We previously described a unique class of acyldepsipeptides (ADEPs) that exerts prominent antibacterial activity against Gram-positive pathogens including streptococci, enterococci, as well as multidrug-resistant Staphylococcus aureus . Here, we report that ADEP prevents cell division in Gram-positive bacteria and induces strong filamentation of rod-shaped Bacillus subtilis and swelling of coccoid S. aureus and Streptococcus pneumoniae . It emerged that ADEP treatment inhibits septum formation at the stage of Z-ring assembly, and that central cell division proteins delocalize from midcell positions. Using in vivo and in vitro studies, we show that the inhibition of Z-ring formation is a consequence of the proteolytic degradation of the essential cell division protein FtsZ. ADEP switches the bacterial ClpP peptidase from a regulated to an uncontrolled protease, and it turned out that FtsZ is particularly prone to degradation by the ADEP–ClpP complex. By preventing cell division, ADEP inhibits a vital cellular process of bacteria that is not targeted by any therapeutically applied antibiotic so far. Their unique multifaceted mechanism of action and antibacterial potency makes them promising lead structures for future antibiotic development.
    Type of Medium: Online Resource
    ISSN: 0027-8424 , 1091-6490
    RVK:
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    Language: English
    Publisher: Proceedings of the National Academy of Sciences
    Publication Date: 2011
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    detail.hit.zdb_id: 1461794-8
    SSG: 11
    SSG: 12
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  • 2
    In: Blood, American Society of Hematology, Vol. 138, No. Supplement 1 ( 2021-11-05), p. 3735-3735
    Abstract: Background In clinical trials, venetoclax has shown high efficacy and good tolerability in patients with chronic lymphocytic leukemia (CLL). Retrospective cohort studies have examined outcomes with venetoclax in B-cell receptor pathway inhibitor (BCRi) naïve and exposed patients with relapsed/refractory (R/R) CLL in the real world setting. However, prospective real-world data on the sequencing of new agents in the R/R setting are limited. The prospective non-interventional observational study VeRVe is assessing effectiveness, safety, and quality of life in CLL patients treated with venetoclax in Austria, Germany, and Switzerland according to local label. Here we report outcomes in patients treated with venetoclax in combination with rituximab (VenR) in BCRi-naïve and BCRi-exposed patients. Methods Adult patients with CLL requiring therapy treated with VenR according to local label were included in this analysis. Patient visits are scheduled at the physician's discretion and according to clinical practice. Study documentation is possible at baseline, weekly during ramp-up, monthly until the end of 6 months and 3-monthly afterwards up to a maximum of 3 years. Response assessment according to iwCLL criteria can be documented at the end of ramp-up, after 3, 12, and 24 months. Analyses were performed for subgroups of BCRi-naïve and BCRi-exposed patients. Results Until April 26, 2021, 94 patients treated with VenR had been enrolled in the ongoing study and had received at least one dose of venetoclax (safety population). For 72 patients, treatment response had been documented at least once (effectiveness population). Enrolled patients had a median of 1 (range 1-10) previous lines of therapy. 57 patients (61%) had previously been treated with chemoimmunotherapy (CIT) and were BCRi-naïve, 32 patients (34%) had received at least one prior BCRi and 7 (7%) had received other prior treatment options. BCRi-naïve patients had a median of 1 prior therapies (range 1-4), while BCRi-exposed patients had received a median of 3 prior therapies (range 1-10). Risk factors were more common in the BCRi-exposed group (38% of patients had a documented del(17p), 34% a TP53 mutation, and 41% an unmutated IGHV status) in comparison to the BCRi-naïve group (14% del(17p), 16% TP53 mutation and 40% unmutated IGHV). Median age at baseline was 72 and 71 years for BCRi-naïve and BCRi-exposed patients, respectively. 65% vs. 84% of BCRi-naive and BCRi-exposed patients had at least one comorbidity. In the BCRi-exposed group, 29 patients (91%) had a BCRi as last prior therapy before VenR initiation with a median duration of prior BCRi therapy of 18 months (range 1 - 61 month). Most frequent reasons for discontinuation of prior BCRi therapy were AE/SAE (11 patients) and disease progression (12 patients). The reported best overall response at 12 months after VenR initiation was 83% (CR+CRi 55%; PR: 28%) for BCRi-naïve and 85% (CR+CRi 30%; PR: 55%) for BCRi-exposed patients (figure 1). After a median follow-up of 315 days the estimated 12-months OS and PFS rate were both 94.8% for BCRi-naïve patients, whereas the estimated 12 months OS and PFS rate for BCRi-exposed patients were 79.1% and 75.7%, respectively, with a median follow-up of 371 days. 79% / 25% of BCRi-naïve and 90% / 44% of BCRi-exposed patients had AEs / SAEs. No new safety signals were observed. Conclusion In this analysis of real-world use of venetoclax in R/R CLL, patients receiving venetoclax in combination with rituximab were predominantly BCRi-naïve. BCRi-exposed patients were more heavily pre-treated, exhibited more genetic high-risk factors, and a higher proportion of patients with comorbidities. Yet, these patients achieved comparable overall response rates. However, complete remissions were more common and the 12 months OS and PFS rates were higher in BCRi-naïve patients. In both groups, VenR treatment was well tolerated. VenR represents a suitable treatment option in BCRi-naïve as well as BCRi-exposed patients. Figure 1 Figure 1. Disclosures Rossi: Gilead: Honoraria, Research Funding; AstraZeneca: Honoraria, Research Funding; Janssen: Honoraria, Research Funding; Verastem: Honoraria, Research Funding; Roche: Honoraria, Research Funding; Abbvie: Honoraria, Research Funding; Cellestia: Honoraria, Research Funding. Hebart: AstraZeneca: Honoraria; Janssen: Honoraria; BMS: Honoraria; AbbVie: Honoraria; Roche: Honoraria. Losem: AbbVie: Honoraria; Amgen: Honoraria. Wolff: Bayer: Honoraria, Research Funding; AbbVie: Honoraria, Research Funding; Teva: Honoraria, Research Funding; Celgene: Honoraria, Research Funding; Novartis: Honoraria, Research Funding; AstraZeneca: Honoraria, Research Funding; Roche: Honoraria, Research Funding. Schmidt: AbbVie: Current Employment. Famulla: AbbVie: Current Employment. Schmidt: Takeda: Honoraria; Biotest: Honoraria; Alexion: Honoraria; Sanofi-Aventis: Honoraria; Novartis: Honoraria; Incyte: Honoraria; AbbVie: Honoraria; Janssen: Honoraria. Noesslinger: Jansen: Honoraria; Roche: Honoraria; Celgene: Honoraria; Gilead: Honoraria; AstraZeneca: Honoraria; AbbVie: Honoraria. Schwaner: AbbVie: Honoraria; Amgen: Honoraria; AstraZeneca: Honoraria; Celgene: Honoraria; Janssen: Honoraria; Novartis: Honoraria; Roche: Honoraria; Servier: Honoraria.
    Type of Medium: Online Resource
    ISSN: 0006-4971 , 1528-0020
    RVK:
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    Language: English
    Publisher: American Society of Hematology
    Publication Date: 2021
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    detail.hit.zdb_id: 80069-7
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  • 3
    In: ChemBioChem, Wiley, Vol. 21, No. 14 ( 2020-07-16), p. 1997-2012
    Abstract: Acyldepsipeptide (ADEP) is an exploratory antibiotic with a novel mechanism of action. ClpP, the proteolytic core of the caseinolytic protease, is deregulated towards unrestrained proteolysis. Here, we report on the mechanism of ADEP resistance in Firmicutes. This bacterial phylum contains important pathogens that are relevant for potential ADEP therapy. For Staphylococcus aureus , Bacillus subtilis , enterococci and streptococci, spontaneous ADEP‐resistant mutants were selected in vitro at a rate of 10 −6 . All isolates carried mutations in clpP . All mutated S. aureus ClpP proteins characterised in this study were functionally impaired; this increased our understanding of the mode of operation of ClpP. For molecular insights, crystal structures of S. aureus ClpP bound to ADEP4 were determined. Well‐resolved N‐terminal domains in the apo structure allow the pore‐gating mechanism to be followed. The compilation of mutations presented here indicates residues relevant for ClpP function and suggests that ADEP resistance will occur at a lower rate during the infection process.
    Type of Medium: Online Resource
    ISSN: 1439-4227 , 1439-7633
    URL: Issue
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    Language: English
    Publisher: Wiley
    Publication Date: 2020
    detail.hit.zdb_id: 2020469-3
    SSG: 12
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  • 4
    In: Blood, American Society of Hematology, Vol. 140, No. Supplement 1 ( 2022-11-15), p. 12412-12413
    Type of Medium: Online Resource
    ISSN: 0006-4971 , 1528-0020
    RVK:
    RVK:
    Language: English
    Publisher: American Society of Hematology
    Publication Date: 2022
    detail.hit.zdb_id: 1468538-3
    detail.hit.zdb_id: 80069-7
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  • 5
    In: Molecular Microbiology, Wiley, Vol. 101, No. 2 ( 2016-07), p. 194-209
    Abstract: The Clp protease complex in Mycobacterium tuberculosis is unusual in its composition, functional importance and activation mechanism. Whilst most bacterial species contain a single ClpP protein that is dispensable for normal growth, mycobacteria have two ClpPs, ClpP1 and ClpP2, which are essential for viability and together form the ClpP1P2 tetradecamer. Acyldepsipeptide antibiotics of the ADEP class inhibit the growth of Gram‐positive firmicutes by activating ClpP and causing unregulated protein degradation. Here we show that, in contrast, mycobacteria are killed by ADEP through inhibition of ClpP function. Although ADEPs can stimulate purified M. tuberculosis ClpP1P2 to degrade larger peptides and unstructured proteins, this effect is weaker than for ClpP from other bacteria and depends on the presence of an additional activating factor (e.g. the dipeptide benzyloxycarbonyl‐leucyl‐leucine in vitro ) to form the active ClpP1P2 tetradecamer. The cell division protein FtsZ, which is a particularly sensitive target for ADEP‐activated ClpP in firmicutes, is not degraded in mycobacteria. Depletion of the ClpP1P2 level in a conditional Mycobacterium bovis BCG mutant enhanced killing by ADEP unlike in other bacteria. In summary, ADEPs kill mycobacteria by preventing interaction of ClpP1P2 with the regulatory ATPases, ClpX or ClpC1, thus inhibiting essential ATP‐dependent protein degradation.
    Type of Medium: Online Resource
    ISSN: 0950-382X , 1365-2958
    URL: Issue
    Language: English
    Publisher: Wiley
    Publication Date: 2016
    detail.hit.zdb_id: 1501537-3
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  • 6
    In: Nature Communications, Springer Science and Business Media LLC, Vol. 6, No. 1 ( 2015-02-19)
    Type of Medium: Online Resource
    ISSN: 2041-1723
    Language: English
    Publisher: Springer Science and Business Media LLC
    Publication Date: 2015
    detail.hit.zdb_id: 2553671-0
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