Azithromycin possesses biofilm–inhibitory activity and potentiates non-bactericidal colistin methanesulfonate (CMS) and polymyxin B against <i>Klebsiella pneumonia</i>

Novel antibiotic combinations may act synergistically to inhibit the growth of multidrug-resistant bacterial pathogens but predicting which combination will be successful is difficult, and standard antimicrobial susceptibility testing may not identify important physiological differences between planktonic free-swimming and biofilm-protected surface-attached sessile cells. Using a nominally macrolide-resistant model Klebsiella pneumoniae strain (ATCC 10031) we demonstrate the effectiveness of several macrolides in inhibiting biofilm growth in multi-well plates, and the ability of azithromycin (AZM) to improve the effectiveness of the antibacterial last-agent-of-choice for K. pneumoniae infections, colistin methanesulfonate (CMS), against biofilms. This synergistic action was also seen in biofilm tests of several K. pneumoniae hospital isolates and could also be identified in polymyxin B disc-diffusion assays on azithromycin plates. Our work highlights the complexity of antimicrobial-resistance in bacterial pathogens and the need to test antibiotics with biofilm models where potential synergies might provide new therapeutic opportunities not seen in liquid culture or colony-based assays

Anecortave acetate as monotherapy for treatment of subfoveal neovascularization in age-related macular degeneration: twelve-month clinical outcomes

To evaluate safety and efficacy of the angiostatic agent anecortave acetate, compared with a placebo, for treatment of subfoveal choroidal neovascularization (CNV). Ongoing masked, randomized, placebo-controlled, parallel evaluation of anecortave acetate (30 mg, 15 mg, and 3 mg) versus a placebo. There were 128 eyes of 128 patients with subfoveal CNV secondary to age-related macular degeneration who were enrolled and treated, with 80% (102/128) of eyes presenting with predominantly classic lesions at baseline. All eyes received a posterior juxtascleral depot application of masked study medication or a placebo, with retreatment at 6-month intervals if the masked investigator believed the patient could benefit. Patients received periodic detailed ophthalmic examinations with both fluorescein and indocyanine green angiography, general physical examinations with electrocardiograms, and hematology/serum chemistry/urinalysis. All ophthalmic and systemic safety data were periodically reviewed by the Independent Safety Committee overseeing the study. Best-corrected logarithm of the minimum angle of resolution (logMAR) vision and fluorescein angiographic lesion characteristics were compared over time and among treatment groups. At month 12, anecortave acetate (15 mg) administered at 6-month intervals was statistically superior to the placebo for 3 measures of clinical efficacy: mean change from baseline vision (P = 0.0131), stabilization of vision ( or = 6 logMAR lines from baseline; P = 0.0224). Subgroup analysis of predominantly classic lesions revealed that anecortave acetate (15 mg) was also superior to the placebo at 1 year for each of these 3 measures of visual outcome (Ps = 0.0022, 0.0100, and 0.0299, respectively). Anecortave acetate (15 mg) trended toward significance over the placebo at month 12 for inhibition of total lesion growth and for inhibition of both the total CNV component and the classic CNV component in both the overall and subgroup analyses. The Independent Safety Committee identified no clinically relevant treatment-related safety issues. Anecortave acetate (15 mg) is safe and clinically efficacious at 1 year for maintaining vision, preventing severe vision loss, and inhibiting subfoveal CNV lesion growt