Comparative efficacy and safety of cefprozil (BMY-28100) and cefaclor in the treatment of acute group A beta-hemolytic streptococcal pharyngitis

Redefining the management of pediatric tonsillopharyngitis with cefprozil

Tonsillopharyngitis is very common in children, with Group A Streptococci being the most common bacterial etiology. Effective antibacterial treatment is imperative due to risk of rheumatic fever. Cephalosporins have been used successfully for the treatment of Group A beta-hemolytic Streptococcal (GABHS) tonsillopharyngitis. Cefprozil is a novel broad-spectrum oral cephalosporin. Cefprozil is rapidly absorbed from the gastrointestinal tract with high bioavailability. The excellent penetration of cefprozil into tonsillar and adenoidal tissue corresponds well with the clinical outcome. The drug provides excellent coverage against both gram-negative and -positive bacteria that may cause pharyngitis/tonsillitis. The beta-lactamase stability of cefprozil appears to exceed that of other oral cephalosporins for important gram negative pathogens. In clinical trials, cefprozil appears to be at least as effective as commonly used comparison agents such as cefaclor and cefixime. Additionally, cefprozil is better tolerated than the latter, especially with regard to gastrointestinal adverse effects. Thus cefprozil can be considered a safe and reliable drug for the treatment of Streptococcal tonsillopharyngitis in children.

Efficacy of cephalexin two vs. three times daily vs. cefadroxil once daily for streptococcal tonsillopharyngitis

The purpose of this study was to compare the bacteriologic and clinical efficacy of oral cephalexin twice vs. three times daily vs. cefadroxil once daily as therapy for group A beta-hemolytic streptococcal (GABHS) tonsillopharyngitis. A prospective open-label, observational cohort study was conducted over 18 months (January 2000-June 2001). Children enrolled had an acute onset of symptoms and signs of a tonsillopharyngeal illness and a laboratory-documented GABHS infection. Follow-up examination and laboratory testing occurred 21 +/- 4 days following enrollment. Two hundred seventy-one patients were enrolled (intent to treat group): 63 received cephalexin twice daily, 124 received cephalexin three times daily, and 84 received cefadroxil once daily. Fifty-three children did not return for the follow-up visit, leaving 218 patients in the per-protocol group: 54 cephalexin twice-daily treated, 94 cephalexin 3-times daily treated, and 70 cefadroxil once-daily treated. In the per-protocol group, bacteriologic cure for those treated with cephalexin twice daily was 87%, for cephalexin 3 times daily, it was 81% and for cefadroxil once daily it was 81% (p = 0.61). The clinical cure rate for cephalexin twice-daily treatment was 91%; for three-times daily, it was 86%; and for cefadroxil once daily, it was 84% (p = 0.56). Because treatment allocation was not randomized, logistic regression analysis was used to adjust for treatment group differences. Younger age of patient was significantly associated with bacteriologic (p = 0.04) and clinical (p = 0.01) failure independent of treatment group but in the adjusted logistic model no differences were found among the 3 treatment regimens. Cephalexin dosed twice daily or three times daily and cefadroxil dosed once daily appear equivalent in bacteriologic and clinical cure of GABHS tonsillopharyngitis.

Antibacterial-induced hepatotoxicity. Incidence, prevention and management

Hepatotoxic reactions to antibacterials are rare, occurring with an estimated frequency of between 1 and 10 per 100,000 drug prescriptions for most antibacterials. Although many antibacterial-induced hepatotoxic reactions have a characteristic clinical and biochemical pattern e.g. cholestatic hepatitis (flucloxacillin) or fatty liver (tetracycline), many can also present with a variety of clinicopathological patterns e.g. nitrofurantoin is associated with the development of acute hepatitis, granulomatous hepatitis and chronic active hepatitis. Almost all reactions are idiosyncratic, with no diagnostic laboratory tests to aid the diagnosis. Early diagnosis is essential and requires a vigilant physician to elicit a detailed drug history. Although the outcome is usually good when the offending antibacterial is withdrawn, morbidity may persist for years and fatalities have occurred, particularly when there is a delay in recognising the hepatotoxic antibacterial. There is no specific treatment for antibacterial-induced hepatotoxicity other than withdrawing the implicated drug. For severe disease, however, liver transplantation should be considered.

Comparison of cefprozil, cefpodoxime proxetil, loracarbef, cefixime, and ceftibuten

OBJECTIVE

To discuss the pharmacokinetics, spectrum of activity, clinical trials, and adverse effects of cefprozil, cefpodoxime proxetil, loracarbef, cefixime, and ceftibuten, an investigational cephalosporin.

DATA SOURCES

Literature was identified by a MEDLINE search from 1986 to January 1995.

STUDY SELECTION

Randomized, controlled studies were selected for evaluation; however, uncontrolled studies were included when data were limited for indications approved by the Food and Drug Administration.

DATA EXTRACTION

Data were evaluated with respect to in vitro activity, study design, clinical and microbiologic outcomes, and adverse drug reactions.

DATA SYNTHESIS

Cefprozil, cefpodoxime proxetil, loracarbef, cefixime, and cefributen are active in vitro against organisms frequently involved in community-acquired infections such as Streptococcus pneumoniae, Escherichia coli, beta-lactamase-positive or -negative Haemophilus influenzae, and Moraxella catarrhalis. Except for cefixime and ceflibuten, they all are active against methicillin-susceptible Staphylococcus aureus. Even though there were problems in study design (discussed within the text), clinical data demonstrate that these new oral beta-lactam compounds are as efficacious as conventional therapies for a variety of community-acquired infections.

CONCLUSIONS

Cefprozil, cefpodoxime, cefixime, loracarbef, and ceftibuten demonstrate in vitro activity against the major organisms that cause community-acquired infections. Clinical trials confirm that these agents are as effective as traditional therapies for the management of acute otitis media, pharyngitis/tonsillitis, sinusitis, bronchitis, pneumonia, urinary tract infections, and skin and skin-structure infections. In addition, cefixime and cefpodoxime are effective therapies for uncomplicated gonococcal infections. Selection of a specific agent will be influenced by susceptibility data and safety, as well as issues of compliance and cost.

Adverse effects of newer cephalosporins. An update

While classifications into generations according to antimicrobial activity has helped clinicians incorporate the increasing number of cephalosporins into their pharmacological repertoire, adverse effects among the different agents fail to follow similar categories. In general, cephalosporins are fairly well tolerated antibiotics, and toxicity has been limited to specific agents. Subtle differences in chemical structure and pharmacokinetics can influence the potential for adverse effects. The route of administration may result in minor adverse reactions, including thrombophlebitis and pain. The most common adverse effects of cephalosporins are allergic reactions, occurring in 0.9 to 3.2% of patients. Cephalosporins have very rarely been associated with haematological toxicity (less than 1% of patients), but specific agents have been associated with neutropenia, hypoprothrombinaemia, haemolytic anaemia, and problems with platelet production and function. Other reactions include localised gastrointestinal disturbances, hepatotoxicity (e.g. biliary sludging), nephrotoxicity and mild central nervous system effects. The cephalosporins are generally well tolerated in the paediatric population. Very few interactions have been observed between cephalosporins and other drugs, largely because cephalosporins do not affect the microsomal P450 hepatic enzyme system. While cephalosporins are considered to be relatively 'safe' drugs, the introduction of newer members warrants continued careful observation for reporting of adverse drug reactions.

Cefprozil versus penicillin V in treatment of streptococcal tonsillopharyngitis

In a randomized multicenter study, the efficacy and safety of cefprozil were compared with those of penicillin in the treatment of group A streptococcal tonsillopharyngitis in children. Of the 409 patients enrolled, 323 were evaluable for their clinical and bacteriological responses; of these 323 children, 172 received cefprozil and 151 received penicillin V. The clinical responses in patients treated with cefprozil were significantly better than those in patients who received penicillin (95.3 versus 88.1%; P = 0.023). Eradication of the original serotype of group A streptococci was achieved in 91.3% of patients treated with cefprozil and 87.4% of patients treated with penicillin, the difference not being statistically significant (P = 0.125). However, there were significantly more symptomatic patients among the bacteriological failures in the penicillin group (68.4%) than in the cefprozil group (26.7%). beta-Lactamase-producing Staphylococcus aureus was more frequently isolated from the throat flora during penicillin therapy than during cefprozil treatment. No difference in the incidence of adverse events probably related or of unknown relationship to the study drugs was observed in the two treatment groups (5.2% of those treated with cefprozil and 6.0% of those treated with penicillin). Cefprozil can be considered a safe and reliable drug for the treatment of streptococcal pharyngitis in children.

Cefprozil

Cefprozil is a new, orally bioavailable, cephalosporin with significant activity against the bacteria commonly associated with upper and lower respiratory tract infection, and skin and soft tissue infections. Its absorption and elimination dynamics suggest once- or twice-daily dosing. The low-rate of gastrointestinal and dermatologic side effects associated with cefprozil administration suggest that it may have a significant role in the management of patients with these infections. Children with pharyngitis or urinary tract infection are more appropriately treated with antibiotics having a narrower spectrum of activity. With a variety of newer cephalosporins being marketed in the early 1990s, it will be important for the clinician to examine the data from ongoing comparative clinical trials to determine which antibiotic is best for a patient with a specific infection and whether the added cost justifies its use.

Cefprozil. A review of its antibacterial activity, pharmacokinetic properties, and therapeutic potential

Cefprozil is an orally active cephalosporin which has demonstrated activity against a wide range of organisms in vitro. It is particularly active against the Gram-positive organisms Streptococcus pyogenes, pneumoniae and agalactiae and against methicillin-susceptible Staphylococcus aureus. Strains of methicillin-resistant S. aureus are not susceptible to cefprozil. Cefprozil is also moderately active against Haemophilus influenzae, Moraxella catarrhalis, Neisseria gonorrhoeae, many Enterobacteriaceae and certain anaerobic organisms, and is relatively stable to hydrolysis by a number of beta-lactamases. In comparative trials, the clinical and bacteriological efficacy of cefprozil 500mg or 20 mg/kg administered once or twice daily has been comparable with multiple daily dosage regimens of erythromycin in patients with tonsillitis or pharyngitis, with cefaclor and amoxicillin/clavulanate in lower respiratory tract infections, with amoxicillin/clavulanate and erythromycin in skin and skin-structure infections and with cefaclor in acute uncomplicated urinary tract infections. The clinical efficacy of cefprozil is similar to that of cefaclor in patients with tonsillitis or pharyngitis but the bacteriological efficacy of cefprozil is significantly greater than that of cefaclor. Cefprozil is clinically more effective than cefuroxime axetil in the treatment of lower respiratory tract infections and demonstrated greater efficacy than cefaclor in one of 2 comparative studies when administered twice daily in patients with skin and skin-structure infections. In children with acute otitis media, cefprozil 15 mg/kg twice daily was as effective as cefaclor or amoxicillin/clavulanate 13.3 mg/kg 3 times daily and was as effective as cefixime 8 mg/kg once daily. The most frequently reported adverse effects associated with cefprozil, diarrhoea and nausea, are usually mild to moderate in severity and discontinuation of treatment is rarely necessary. Thus, cefprozil with its convenient administration regimen appears to be a suitable alternative to cefaclor, cefixime, amoxicillin/clavulanate or erythromycin for the treatment of upper and lower respiratory tract infections, skin and skin-structure infections, and otitis media in children. While cefprozil has shown similar efficacy to cefaclor in the treatment of uncomplicated urinary tract infections, well-controlled clinical trials comparing its efficacy with that of cotrimoxazole (trimethoprim+sulfamethoxazole) in this indication are required.