Cefixime in the treatment of patients with lower respiratory tract infections: results of US clinical trials

Identification of hACE2-interacting sites in SARS-CoV-2 spike receptor binding domain for antiviral drugs screening

The key structure of the interface between the spike protein of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) and human angiotensin-converting enzyme 2 (hACE2) acts as an essential switch for cell entry by the virus and drugs targets. However, this is largely unknown. Here, we tested three peptides of spike receptor binding domain (RBD) and found that peptide 391-465 aa is the major hACE2-interacting sites in SARS-CoV-2 spike RBD. We then identified essential amino acid residues (403R, 449Y, 454R) of peptide 391-465 aa that were critical for the interaction between the RBD and hACE2. Additionally, a pseudotyped virus containing SARS-CoV-2 spike with individual mutation (R454G, Y449F, R403G, N439I, or N440I) was determined to have very low infectivity compared with the pseudotyped virus containing the wildtype (WT) spike from reference strain Wuhan 1, respectively. Furthermore, we showed the key amino acids had the potential to drug screening. For example, molecular docking (Docking) and infection assay showed that Cephalosporin derivatives can bind with the key amino acids to efficiently block infection of the pseudoviruses with wild type spike or new variants. Moreover, Cefixime inhibited live SARS-CoV-2 infection. These results also provide a novel model for drug screening and support further clinical evaluation and development of Cephalosporin derivatives as novel, safe, and cost-effective drugs for prevention/treatment of SARS-CoV-2.

PEPT1- and OAT1/3-mediated drug-drug interactions between bestatin and cefixime in vivo and in vitro in rats, and in vitro in human

The purpose of the present study was to elucidate the transporter-mediated pharmacokinetics mechanism of drug-drug interactions (DDIs) between bestatin and cefixime. The plasma concentrations and bioavailabilities of bestatin and cefixime were decreased after oral co-administration in rats. The uptake in rat everted intestinal sacs of bestatin and cefixime were dramatically declined after co-administration of the two drugs. Bestatin and cefixime can mutually competitively inhibit the uptake by hPEPT1-HeLa cells. The plasma concentrations of bestatin and cefixime were increased; however, the cumulative biliary excretion had no significant change, and the cumulative urinary excretion and renal clearance of the two drugs in rats decreased after intravenous coadministration. Moreover, decreased uptake of the two drugs was observed in human kidney slices, rat kidney slices and hOAT1/hOAT3-transfected HEK293 cells when bestatin and cefixime were coadministered. The accumulation of bestatin and cefixime in kidney slices can be inhibited by p-aminohippurate, benzylpenicillin and probenecid, but not by tetraethyl ammonium. The results suggest that intestinal absorption and renal excretion of bestatin and cefixime can be inhibited when the two drugs were co-administered in rats. The pharmacokinetic mechanism indicates that the DDIs between bestatin and cefixime are mainly mediated by Pept1 and Oat1/3 in rats. PEPT1 and OAT1/3 are the target transporters of DDIs between bestatin and cefixime in human kidney slices and human transfected cells, proposing possible drug-drug interaction in humans.

Efficacy and Tolerability of 5- vs 10-Day Cefixime Therapy in Acute Exacerbations of Chronic Bronchitis

The efficacy and tolerability of oral cefixime 400mg once daily for 5 days was compared with standard 10-day therapy in a multicentre, double-blind, randomised, controlled clinical trial of 222 patients with acute exacerbations of chronic bronchitis. Clinical and bacteriological efficacy were assessed after 6, 11 and 30 days. A total of 167 patients were evaluable for efficacy on a per-protocol basis. Clinical efficacy (cure or improvement based on the quality and quantity of expectorated sputum and symptoms of dyspnoea) at day 11 was statistically equivalent (p < 0.01) between the treatment groups, with a successful clinical response achieved in 91% (5-day) and 89% (10-day) of patients. Bacteriological efficacy was also similar with 5- and 10-day treatment. During treatment, more patients reported an adverse event possibly or probably related to the study medication in the 10-day than in the 5-day treatment group (19 vs 14%). However, this difference was not statistically significant. Oral cefixime 400mg once daily is an effective and well tolerated treatment for acute exacerbations of chronic bronchitis. Short-term (5-day) therapy offers clinical efficacy similar to that of standard (10-day) therapy.

Children with pneumonia: how do they present and how are they managed?

OBJECTIVE

To describe the spectrum of clinical features and management of community acquired pneumonia in the UK.

DESIGN

Prospectively recorded clinical details for all children with possible pneumonia and chest x ray (CXR) changes in 13 hospitals in the North of England between 2001 and 2002.

RESULTS

89% of 711 children presenting to hospital with pneumonia were admitted; 96% received antibiotics, 70% intravenously. 20% had lobar CXR changes, 3% empyema and 4% required intensive care. Respiratory rate (RR), hypoxia and dyspnoea all correlated with each other and prompted appropriate interventions. Admission in children, not infants, was independently associated with RR, oxygen saturation, lobar CXR changes and pyrexia. Neither C-reactive protein, lobar CXR changes or pyrexia were associated with severity. Children over 1 year old with perihilar CXR changes more often had severe disease (p = 0.001). Initial intravenous antibiotics were associated with lobar CXR changes in infants and children and with dyspnoea, pyrexia and pleural effusion in children. The presence of pleural effusion increased duration of antibiotic treatment (p<0.001). Cefuroxime was the most often used intravenous antibiotic in 61%. Oral antibiotics included a penicillin in 258 (46%), a macrolide in 192 (34%) and a cephalosporin in 117 (21%). Infants stayed significantly longer (p<0.001) as did children with severe disease (p<0.01), effusions (p = 0.005) or lobar CXR changes (p< or =0.001).

CONCLUSIONS

There is a high rate of intravenous antibiotic administration in hospital admissions for pneumonia. Despite lobar CXR changes not being independently associated with severe disease, initial lobar CXR changes and clinical assessment in children independently influenced management decisions, including admission and route of antibiotics.