Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0040425 (tonsillitis)
 1,594 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Telithromycin is a new ketolide antimicrobial, specifically developed for the treatment of community-acquired respiratory tract infections. It has a wide spectrum of antibacterial activity against common respiratory pathogens including Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis and Streptococcus pyogenes. It also has activity against atypical pathogens, such as Chlamydia pneumoniae, Legionella pneumophila and Mycoplasma pneumoniae. Telithromycin maintains activity against beta-lactam and macrolide-resistant respiratory tract pathogens and does not appear to induce cross-resistance to other members of the macrolide-lincosamide-streptogramin (MLS) group of antimicrobials. It demonstrates bactericidal activity against S. pneumoniae and H. influenzae and has a prolonged concentration-dependent post-antibiotic effect (PAE) in vitro. The drug has favourable pharmacokinetics following oral administration. It is well absorbed, achieves good plasma levels and is highly concentrated in pulmonary tissues and white blood cells. In clinical trials, telithromycin given orally at a dose of 800 mg once daily for 5 - 10 days was as effective as comparator antimicrobials for the treatment of adults with community-acquired pneumonia, acute exacerbations of chronic bronchitis, acute maxillary sinusitis and group A-beta-haemolytic streptococcal pharyngitis or tonsillitis. The adverse events and safety profile were similar to comparator antimicrobials. The most common adverse events were diarrhoea, nausea, headache and dizziness. Telithromycin should provide an effective, convenient and well-tolerated once-daily oral therapy for treatment of respiratory infections.
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PMID:Telithromycin: a new ketolide antimicrobial for treatment of respiratory tract infections. 1117 47

Telithromycin is the first member of a new family of the macrolide-lincosamide-streptogramin-B (MLS(B)) class of antimicrobials, the ketolides. It has a good spectrum of activity against respiratory pathogens, including penicillin- and erythromycin-resistant pneumococci, as well as intracellular and atypical bacteria. Furthermore, it has a low potential to select for resistance or induce cross-resistance among other MLS(B) antimicrobials. At the recommended dosage of 800 mg orally once daily, telithromycin reaches maximal plasma concentrations of about 2 mg/L. It penetrates rapidly into bronchopulmonary, tonsillar, sinus and middle ear tissues and/or fluids and achieves high concentrations at sites of infection. It also concentrates within polymorphonuclear neutrophils. In clinical trials in patients with community-acquired pneumonia (CAP), acute exacerbations of chronic bronchitis (AECB) or pharyngitis/tonsillitis caused by group A beta-haemolytic streptococci, telithromycin 800 mg once daily achieved clinical cure rates of 86 to 95%. In acute maxillary sinusitis (AMS), cure rates were 73 to 91%. A 7- to 10-day regimen of telithromycin was as effective as a 10-day course of amoxicillin 1000 mg 3 times daily, clarithromycin 500 mg twice daily or a 7- to 10-day course of trovafloxacin 200 mg once daily for treating CAP. A 5-day regimen of telithromycin was as effective as a 10-day regimen of cefuroxime axetil 500 mg twice daily or amoxicillin/clavulanic acid 500/125 mg 3 times daily in AECB. A 5-day regimen of telithromycin was as effective as a 10-day regimen of clarithromycin 250 mg twice daily or phenoxymethylpenicillin 500 mg 3 times daily in pharyngitis/tonsillitis, or a 10-day regimen of amoxicillin/clavulanic acid 500/125 mg 3 times daily in patients with AMS. Telithromycin was well tolerated across all patient populations. Adverse events associated with telithromycin were generally mild to moderate in intensity and seldom led to treatment discontinuation. The most frequent adverse events were diarrhoea (13.3%) and nausea (8.1%). Other adverse events included dizziness and vomiting.
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PMID:Telithromycin. 1139 13

Among adults, acute sinusitis, tonsillitis/pharyngitis, community-acquired pneumonia (CAP) and acute exacerbations of chronic bronchitis (AECB) are the most commonly encountered respiratory tract infections (RTIs) in the community. Empiric antibacterial therapy is the most widely used approach for the treatment of such infections. The appropriate antibacterial requires consideration of a number of patient-, pathogen- and drug-related factors. One additional factor is the global spread of resistance among common respiratory pathogens such as Streptococcus pneumoniae, Haemophilus influenzae and Moraxella catarrhalis, which limits the utility of existing antibacterials. Telithromycin (HMR 3647), the first of a new family of antibacterials, the ketolides, was designed specifically to provide optimal therapy for community-acquired RTIs. This agent, which has a broad spectrum of antibacterial activity against common respiratory pathogens (including resistant strains and atypical/intracellular organisms), has been clinically and bacteriologically evaluated against gold-standard comparators in a series of phase III clinical trials. The results of these studies demonstrate that telithromycin, at a dosage of 800 mg once daily, is an effective, well-tolerated agent for the treatment of the most commonly encountered community-acquired RTIs. Moreover, telithromycin meets the challenge of increasing antibacterial resistance. High rates of clinical cure and bacteriologic eradication were achieved, even in patients infected with problematic resistant pathogens such as penicillinG- and macrolide-resistant S. pneumoniae. In summary, telithromycin represents a promising new antibacterial for the treatment of community-acquired RTIs. With high efficacy and bacterial eradication rates, good tolerability and convenient once-daily administration, telithromycin therapy should result in increased patient compliance and improved outcomes, thereby minimizing the risk of developing antibacterial resistance.
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PMID:Clinical management of respiratory tract infections in the community: experience with telithromycin. 1178 52

This randomized, double-blind study compared the efficacy and safety of a 5-d course of the new ketolide antimicrobial, telithromycin, with those of a standard 10-d course of penicillin V (phenoxymethylpenicillin) in patients with group A beta-hemolytic streptococci (GABHS) pharyngitis/tonsillitis. Patients aged 15-65 y (n = 395) with clinical signs and symptoms of pharyngitis/tonsillitis and a positive streptococcal antigen test or throat culture for GABHS were randomized to receive either telithromycin 800 mg once daily for 5 d (n = 198) or penicillin V 500 mg three times daily for 10 d (n = 197). Clinical and bacteriologic outcomes were assessed at post-therapy, test-of-cure (Days 16-20) and late post-therapy (Days 38-45) visits. Telithromycin for 5 d was equivalent to 10 d of penicillin V in terms of bacteriologic and clinical outcome (per-protocol): at post-therapy, test-of-cure visit, bacteriologic outcome was satisfactory in 84.3% and 89.1% of patients in the telithromycin and penicillin V groups, respectively, while clinical cure was achieved in 94.8% and 94.1% of patients, respectively. At late post-therapy, 82.4% of patients treated with telithromycin achieved a satisfactory bacteriologic outcome, compared with 84.7% of penicillin V recipients. The GABHS eradication rates for telithromycin and penicillin post-therapy were 85.2% and 89.1%, respectively, and 86.1% and 86.5%, respectively at late post-therapy. Both treatments were well tolerated, with a similar overall incidence of treatment-emergent adverse events. Short-course (5 d) therapy with telithromycin 800 mg once daily is comparable to a standard 10 d course of penicillin V for the treatment of GABHS pharyngitis/tonsillitis in adults and adolescents.
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PMID:Efficacy of short-course therapy with the ketolide telithromycin compared with 10 days of penicillin V for the treatment of pharyngitis/tonsillitis. 1186 59

The ketolide telithromycin (HMR-3647; Ketek), a derivative of clarithromycin, has been launched by Aventis Pharma (formerly Hoechst Marion Roussel) for the treatment of respiratory tract infections with gram-positive or gram-negative cocci, Haemophilus influenzae, Streptococcus pneumoniae, Moraxella catarrhalis, intracellular pathogens, atypical microorganisms, toxoplasma or anaerobic bacteria. By May 2001, filings in the US and EU had been completed and a filing in Japan was expected to take place in the fourth quarter of 2001. In July 2001, telithromycin was granted marketing authorization by the EC for the treatment of community-acquired respiratory tract infections, including those caused by bacteria resistant to commonly used antibiotics. In October 2001, the product was launched in Germany. In March 2000, telithromycin was submitted to the US FDA and the EMEA, under the EU centralized approval procedure, for approval for the treatment of community-acquired pneumonia (CAP), acute sinusitis, acute exacerbations of chronic bronchitis and tonsillitis/pharyngitis. The company had expected to launch the product in early 2001. The CPMP issued a positive opinion for all four indications on April 23 2001. In September 2001, the company indicated that it expected the product to be launched in Japan in 2002. The FDA's Anti-infectives Advisory Committee was due to review telithromycin for all the submitted indications on January 29 2001; however, this was postponed. This postponement was thought to be at Aventis' request in order to discuss the potential for a resistant pneumococcal infection labeling which would boost product sales. The revised date for the meeting was April 26 2001, at which the Anti-Infective Drugs Advisory Committee of the FDA recommended approval of telithromycin for the treatment of CAP in patients 18 years of age or older. The committee failed to recommend approval for the use of the drug for the remaining three indications for which it was filed, citing concerns over potential cardiovascular risk and liver toxicity; at this time, the company was in active discussions with the FDA regarding approval of the remaining three indications. An approvable letter for CAP, acute bacterial exacerbations of chronic bronchitis and acute bacterial sinusitis was received by the company in June 2001; Aventis also received a non-approvable letter for the treatment of tonsillitis/pharyngitis at this time. In April 1999, ABN Amro predicted annual sales of DM 50 million in 2001, rising to DM 100 million in 2002. In February 1999, Lehman Brothers estimated a 70% probability that this ketolide would come to market. The analysts also estimated a launch date of 2001, with peak sales of US $700 million in 2009. Analysts Merrill Lynch predicted in September 200, that the product would be launched by 2001, with sales of euro 50 million in that year, rising to euro 284 million in 2004. Deutsche Bank predicted in August 2001, that sales of the product would reach euro 5 million in 2001, rising to euro 300 million in 2005. Analysts at Merrill Lynch predicted in November 2001, that the product would be resubmitted in the US in mid-2002, and would make sales of US $5 million in 2001, rising to US $250 million in 2004.
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PMID:Telithromycin. Aventis Pharma. 1189 30

Telithromycin, the first ketolide antibiotic to undergo clinical development, has been specifically designed to treat community-acquired respiratory tract infections, including those caused by resistant pathogens. Like macrolides, telithromycin inhibits protein synthesis by acting mainly on the 50S ribosomal subunit. The defining structural characteristic is a keto function in place of the C3-cladinose moiety, which greatly improves acid stability and confers a lack of induction of MLSb resistance. Telithromycin provides potent activity against a wide spectrum of Gram-positive and Gram-negative organisms, including erythromycin-resistant pneumococci and atypical/intracellular organisms. Preliminary results from clinical trials have demonstrated that telithromycin may provide a convenient and effective compact treatment option for select respiratory tract infections such as community-acquired pneumonia, acute bacteria exacerbations of chronic bronchitis, acute sinusitis and tonsillitis/pharyngitis. (c) 2001 Prous Science. All rights reserved.
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PMID:Telithromycin (HMR 3647): The first ketolide antibiotic. 1274 33

Telithromycin is the first ketolide antibacterial to be approved for clinical use. The ketolides represent a novel class of antibacterial agents structurally related to the macrolides, which has been developed specifically to offer an optimal spectrum for the treatment of upper and lower respiratory tract infections (RTIs) caused by common and atypical pathogens, including strains that are resistant to currently used antibiotics. The innovative structural changes that distinguish telithromycin from macrolides contribute to its unique microbiological profile. Its well-balanced spectrum of antibacterial activity is highly appropriate for the empirical treatment of upper and lower community-acquired RTIs, offering activity against common, including resistant, and atypical/intracellular pathogens. Furthermore, telithromycin demonstrates a low propensity to select for or induce resistance to macrolide-lincosamide-streptogramin antibacterials. A once-daily dose of telithromycin 800 mg rapidly achieves high concentrations in both plasma and respiratory tissues and fluids and is maintained at effective levels throughout the 24-hour dosing period. In clinical trials, telithromycin has demonstrated high clinical and bacteriological efficacy in the treatment of community-acquired pneumonia, acute exacerbations of chronic bronchitis, acute sinusitis and group A beta-haemolytic streptococcal tonsillitis/pharyngitis. High efficacy was maintained in those patient groups considered to be at high risk of complications and those with infections caused by penicillin and/or macrolide (erythromycin) resistant Streptococcus pneumoniae. Together with its favourable tolerability profile and short course of once-daily therapy, these properties indicate that telithromycin will be a valuable new antibacterial for the empirical treatment of community-acquired RTIs.
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PMID:Telithromycin: the first ketolide antibacterial for the treatment of community-acquired respiratory tract infections. 1291 92

Telithromycin, a recently approved ketolide antibiotic derived from 14-membered macrolides, is active against erythromycin-resistant pneumococci. Telithromycin has enhanced activity in vitro because it binds not only to domain V of ribosomal RNA (like macrolides do) but also to domain II. However, it is not active against streptococci and staphylococci with constitutive macrolide, lincosamide, and streptogramin B resistance. Telithromycin, available in an oral formulation, is approved by the US Food and Drug Administration for use in adults for treatment of (1) community-acquired pneumonia due to Streptococcus pneumoniae (including multidrug-resistant isolates), Haemophilus influenzae, Moraxella catarrhalis, Chlamydia pneumoniae, or Mycoplasma pneumoniae; (2) acute exacerbation of chronic bronchitis due to S. pneumoniae, H. influenzae, or M. catarrhalis; or (3) acute bacterial sinusitis due to S. pneumoniae, H. influenzae, M. catarrhalis, or methicillin- and erythromycin-susceptible Streptococcus aureus. It is not approved for treatment of tonsillitis, pharyngitis, or severe pneumococcal pneumonia. Unique visual adverse effects occurred in 0.27%-2.1% of patients receiving telithromycin therapy. Its enhanced activity against some common respiratory pathogens makes it a valuable addition to the available macrolides.
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PMID:Telithromycin: a ketolide antibiotic for treatment of respiratory tract infections. 1588 65

The ketolides are a new subclass of macrolides, and telithromycin is the first of these agents to be approved. Modifications to the basic macrolide structure result in enhanced activity against penicillin- and erythromycin resistant respiratory pathogens. It is therefore an option in the treatment of mild to moderate community-acquired respiratory infections, such as pneumonia, acute exacerbations of chronic bronchitis, pharyngitis/tonsillitis, and sinusitis. Telithromycin also offers the advantages of once-daily dosing and a shorter course of therapy in certain infections. Comparative clinical trials, although limited and involving only a small number of resistant organisms, showed the equivalence of telithromycin to existing therapies, although telithromycin generally had a higher frequency of mild to moderate gastrointestinal adverse effects. Further clinical and safety data, especially in patients with resistant organisms, are needed.
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PMID:Telithromycin: a novel agent for the treatment of community-acquired upper respiratory infections. 1620 Jan 39

Data are presented on antimicrobial resistance among isolates of Streptococcus pneumoniae, Streptoco-ccus pyogenes, Haemophilus influenzae, and Moraxella catarrhalis collected in Japan during years 1-3 (1999-2002) of the Prospective Resistant Organism Tracking and Epidemiology for the Ketolide Telithromycin (PROTEKT) surveillance study. In addition to the standard panel of PROTEKT antimicrobial agents, eight other agents often used in Japan also were tested against these isolates. The majority (30%-55%) of S. pneumoniae and H. influenzae isolates were collected from patients with community-acquired pneumonia, whereas most (>70%) S. pyogenes isolates came from patients with tonsillitis/pharyngitis. Penicillin and macrolide resistance were high among isolates of S. pneumoniae, averaging 30.9%-44.5% and 77.2%-79.9%, respectively, across all centers over the 3 study years; the highest occurrences were reported among pediatric patients aged 0-2 years. The erm(B) genotype accounted for >50% of all erythromycin-resistant isolates each study year. S. pyogenes isolates were highly susceptible to most antimicrobial agents except the macrolides and tetracycline. beta-Lactamase production among H. influenzae isolates range was 8.5%-9.7% per annum. A total of 9 beta-lactamase-negative, ampicillin-resistant isolates were collected during the study. Almost all (>95%) M. catarrhalis isolates were beta-lactamase positive each year. Telithromycin was highly active against all pathogens examined in this study during all 3 years.
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PMID:Antimicrobial susceptibility of respiratory tract pathogens in Japan during PROTEKT years 1-3 (1999-2002). 1650 84


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