Telithromycin 400mg tablets

INTRODUCTION: A pharmacoeconomic analysis model was developed to evaluate the cost-effectiveness of antibiotics from a societal perspective in Korea and China. A network meta-analysis was conducted to evaluate the efficacy of antibiotics. METHODOLOGY: We conducted a systematic search for randomized controlled trials or quasi-randomized controlled trials on antibiotics employed as therapy in scrub typhus management. We performed a network meta-analysis to obtain their relative efficacy. The outcome measures for efficacy were cure rate and non-relapse rate. To evaluate their relative cost-effectiveness in Korea and China, a decision analytic model simulating a cohort of scrub typhus patients using antibiotics as therapy was constructed from a societal perspective over 8 weeks. The number of cure cases per 1000 patients and the incremental cost-effectiveness ratio (ICER) was calculated. RESULTS: We identified 11 relevant articles for network meta-analysis. Of the seven comparisons (azithromycin, chloramphenicol, doxycycline, high-dose rifampin, low-dose rifampin, telithromycin, tetracycline) included in the network meta-analysis, tetracycline was the most effective drug for the treatment of scrub typhus, but the difference is not significant. In the cost-effectiveness analysis, all the treatments were dominated by tetracycline in Korea and China. CONCLUSIONS: Tetracycline is the most economic drug for the treatment of scrub typhus. Hence, tetracycline is recommended as the first choice for the treatment of scrub typhus without contraindications in China and Korea.

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BACKGROUND: The emergence of bacterial resistance to commonly used antibiotics, such as macrolides, is complicating the management of respiratory tract infections (RTIs). Telithromycin, a ketolide antimicrobial structurally related to macrolides, is approved for the treatment of community-acquired RTIs, and shows lower pathogen resistance rates. The purpose of this study was to compare the efficacy and safety of telithromycin with clarithromycin, a macrolide routinely used as therapy for RTIs. METHODS: We performed a meta-analysis of relevant randomized-controlled trials (RCTs) identified in PubMed, the Cochrane Library, Embase, CNKI and VIP databases. The primary efficacy outcome was clinical treatment success assessed at the test-of-cure time in the per-protocol population, and the primary safety outcome was drug related adverse effects. RESULTS: Seven RCTs, involving 2845 patients with RTIs, were included in the meta-analysis. Oral telithromycin and clarithromycin showed a similar clinical treatment success in modified intention to treat and per-protocol population (cure and improvement) (odds ratios (ORs): 0.84, 95% confidence intervals (CI): 0.64 - 1.11 and OR: 1.14, 95%CI: 0.71 - 1.85, respectively). Similar findings were obtained for secondary efficacy outcomes: clinical treatment success at a late post-therapy visit (OR: 0.92, 95%CI: 0.57 - 1.48) and microbiological treatment success at the test-of-cure time (OR: 1.14; 95%CI: 0.71 - 1.85). The safety outcome analysis indicated telithromycin had a similar risk of drug-related adverse effect and serious adverse effect with clarithromycin. CONCLUSIONS: Our findings indicate that oral telithromycin and clarithromycin have similar treatment efficacy and adverse effect. The advantages of lower antimicrobial resistance rates, once-daily short-duration dosing and reported lower health-care costs make oral telithromycin a useful option for the empiric management of mild-to-moderate RTIs.

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Abstract Conventional macrolide-lincosamide-streptogramin B-ketolide (MLS B K) antibiotics are unable to counter the growing challenge of antibiotic resistance that is conferred by the constitutive methylation of rRNA base A2058 or its G2058 mutation, while the presence of unmodified A2058 is crucial for high selectivity of traditional MLS B K in targeting pathogens over human cells. The absence of effective modes of action reinforces the prevailing belief that constitutively antibiotic-resistant Staphylococcus aureus remains impervious to existing macrolides including telithromycin. Here, we report the design and synthesis of a novel series of macrolides, featuring the strategic fusion of ketolide and quinolone moieties. Our effort led to the discovery of two potent compounds, MCX-219 and MCX-190, demonstrating enhanced antibacterial efficacy against a broad spectrum of formidable pathogens, including A2058-methylated Staphylococcus aureus , Streptococcus pneumoniae , Streptococcus pyogenes , and notably, the clinical Mycoplasma pneumoniae isolates harboring A2058G mutations which are implicated in the recent pneumonia outbreak in China. Mechanistic studies reveal that the modified quinolone moiety of MCX-190 establishes a distinctive secondary binding site within the nascent peptide exit tunnel. Structure-activity relationship analysis underscores the importance of this secondary binding, maintained by a sandwich-like π–π stacking interaction and a water–magnesium bridge, for effective engagement with A2058-methylated ribosomes rather than topoisomerases targeted by quinolone antibiotics. Our findings not only highlight MCX-219 and MCX-190 as promising candidates for next-generation MLS B K antibiotics to combat antibiotic resistance, but also pave the way for the future rational design of the class of MLS B K antibiotics, offering a strategic framework to overcome the challenges posed by escalating antibiotic resistance.

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ABSTRACT Biofilm formation is an important characteristic of many Staphylococcus aureus infections because it limits the efficacy of host defenses and conventional antibiotic therapy. There are many literature reports that describe small molecule inhibitors of S. aureus biofilm formation, but the lack of direct comparisons and differences in the methods used to assess inhibition make it impossible to assess the efficacy of these compounds relative to each other. To address this, we compared 19 compounds reported in the literature to be inhibitors of S. aureus biofilm formation. We used the methicillin-susceptible clinical osteomyelitis isolate UAMS-1 in a microtiter plate biofilm assay shown to maximize biofilm formation and provide results consistent with those observed in vivo . Under these conditions, telithromycin (Ketek) showed the greatest inhibitory activity, limiting biofilm formation to a degree comparable to a UAMS-1 sarA mutant at a concentration of 0.49 µM (0.40 µg/mL). Similar results were obtained for the methicillin-resistant USA300 strain LAC. Telithromycin is a bacteriostatic ketolide antibiotic that is not currently approved in the United States for use as an antibiotic due to its concerning safety profile. However, the concentration required to limit growth in vitro was higher than the concentration required to limit biofilm formation, suggesting that low-dose telithromycin might be useful to limit biofilm formation and increase the efficacy of other antibiotics in biofilm-associated infections. Irrespective of whether telithromycin is ultimately proven clinically useful in this regard, these results emphasize the need for widespread use of a standardized in vitro approach to evaluate prospective inhibitors. IMPORTANCE Because biofilm formation is such a problematic feature of Staphylococcus aureus infections, much effort has been put into identifying biofilm inhibitors. However, the results observed with these compounds are often reported in isolation, and the methods used to assess biofilm formation vary between labs, making it impossible to assess relative efficacy and prioritize among these putative inhibitors for further study. The studies we report address this issue by directly comparing putative biofilm inhibitors using a consistent in vitro assay. This assay was previously shown to maximize biofilm formation, and the results observed with this assay have been proven to be relevant in vivo . Of the 19 compounds compared using this method, many had no impact on biofilm formation under these conditions. Indeed, only one proved effective at limiting biofilm formation without also inhibiting growth.

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BACKGROUND: This study aims to explore the antibacterial activity of cethromycin against Staphylococcus aureus (S. aureus), and its relationship with multilocus sequence typing (MLST), erythromycin ribosomal methylase (erm) genes and macrolide-lincosamide-streptogramin B (MLSB) phenotypes of S. aureus. RESULTS: The minimum inhibitory concentrations (MICs) of cethromycin against 245 S. aureus clinical isolates ranged from 0.03125 to ≥ 8 mg/L, with the resistance of 38.8% in 121 methicillin-resistant S. aureus (MRSA). This study also found that cethromycin had strong antibacterial activity against S. aureus, with the MIC ≤ 0.5 mg/L in 55.4% of MRSA and 60.5% of methicillin-sensitive S. aureus (MSSA), respectively. The main MLSTs of 121 MRSA were ST239 and ST59, and the resistance of ST239 isolates to cethromycin was higher than that in ST59 isolates (P = 0.034). The top five MLSTs of 124 MSSA were ST7, ST59, ST398, ST88 and ST120, but there was no difference in the resistance of MSSA to cethromycin between these STs. The resistance of ermA isolates to cethromycin was higher than that of ermB or ermC isolates in MRSA (P = 0.016 and 0.041, respectively), but the resistance of ermB or ermC isolates to cethromycin was higher than that of ermA isolates in MSSA (P = 0.019 and 0.026, respectively). The resistance of constitutive MLSB (cMLSB) phenotype isolates to cethromycin was higher than that of inducible MLSB (iMLSB) phenotype isolates in MRSA (P < 0.001) or MSSA (P = 0.036). The ermA, ermB and ermC genes was mainly found in ST239, ST59 and ST1 isolates in MRSA, respectively. Among the MSSA, the ermC gene was more detected in ST7, ST88 and ST120 isolates, but more ermB genes were detected in ST59 and ST398 isolates. The cMLSB phenotype was more common in ST239 and ST59 isolates of MRSA, and was more frequently detected in ST59, ST398, and ST120 isolates of MSSA. CONCLUSION: Cethromycin had strong antibacterial activity against S. aureus. The resistance of MRSA to cethromycin may had some clonal aggregation in ST239. The resistance of S. aureus carrying various erm genes or MLSB phenotypes to cethromycin was different.

Abstract licence: CC BY