Delivering macrolide antibiotics to heal a broken heart - And other inflammatory conditions

Drug carriers to deliver macrolide antibiotics, such as azithromycin, show promise as antibacterial agents. Macrolide drug carriers have largely focused on improving the drug stability and pharmacokinetics, while reducing adverse reactions and improving antibacterial activity. Recently, macrolides have shown promise in treating inflammatory conditions by promoting a reparative effect and limiting detrimental pro-inflammatory responses, which shifts the immunologic setpoint from suppression to balance. While macrolide drug carriers have only recently been investigated for their ability to modulate immune responses, the previous strategies that deliver macrolides for antibacterial therapy provide a roadmap for repurposing the macrolide drug carriers for therapeutic interventions targeting inflammatory conditions. This review describes the antibacterial and immunomodulatory activity of macrolides, while assessing the past in vivo evaluation of drug carriers used to deliver macrolides with the intention of presenting a case for increased effort to translate macrolide drug carriers into the clinic.

Characteristics and evaluation of an injectable clarithromycin lipid-based complex in vitro and in vivo

The purpose of this paper is to prepare a less-irritating and lipid-based clarithromycin complex (LCC) by the route of intravenous administration qualified with high drug-loading and fine particle size. The LCC was prepared by the injection of organic solvent phase (containing clarithromycin, sodium cholesterol sulfate and phospholipid at a molar ratio of 1:1:1.5) into the Tris buffer solution (0.05 M, pH 7.2) at 40 °C, and then was concentrated by ultrafiltration to remove the organic solvent. The technique of lyophilization was applied to obtain the LCC lyophilized products. Evaluation of the injectable LCC was performed by particle sizes analysis, transmission electron microscope, entrapment efficiency, stability and irritation tests. The LCC possessed a log-normal size distribution with an average size of 75.4 nm. The drug entrapment efficiency was above 97.0%, which was influenced by the amount of phospholipid, pH value of the media and ionic strength of aqueous suspension. The results of stability and irritation tests proved that LCC had more stability and less irritation. This unique LCC formulation may be applied to the human by the route of injection with less or no irritation. LCC could be an appropriate candidate for intravenous preparation and has a great potential for clinical and industrial-scale production.

13 – Antibiotic therapy of community-acquired pneumonia (CAP) caused by atypical agents

Macrolides, fluoroquinolones, doxycycline, and ketolides show a good intrinsic activity against intracellular pathogens which are responsible for a variable percentage of community-acquired pneumonia (CAP). These therapeutic agents all seem effective in treating most cases of CAP caused by Mycoplasma pneumoniae, Chlamydia pneumoniae, or Legionella spp. Among quinolones, the more recent fluoroquinolones, such as gemifloxacin or moxifloxacin, generally show a better intrinsic activity than the older ones. Among macrolides, azithromycin, and clarithromycin show a better pharmacokinetic profile. Both of them are available in intravenous form. It is quite common for M. pneumoniae and C. pneumoniae to continue to be shed in respiratory secretions, weeks after an effective therapy. The clinical relevance of this finding is not clear since most of these patients have a good outcome. Azithromycin, due to its advantageous pharmacokinetic profile, seems the best option when antibiotic prophylaxis is considered in some epidemiological settings. It has been proved effective in closed M. pneumoniae outbreaks.