Peroral Amphotericin B Polymer Nanoparticles Lead to Comparable or Superior In Vivo Antifungal Activity to That of Intravenous Ambisome® or Fungizone™

Background: Despite advances in the treatment, the morbidity and mortality rate associated with invasive aspergillosis remains unacceptably high (70–90%) in immunocompromised patients. Amphotericin B (AMB), a polyene antibiotic with broad spectrum antifungal activity appears to be a choice of treatment but is available only as an intravenous formulation; development of an oral formulation would be beneficial as well as economical. Methodology: Poly(lactide-co-glycolode) (PLGA) nanoparticles encapsulating AMB (AMB-NPs) were developed for oral administration. The AMB-NPs were 113±20 nm in size with ~70% entrapment efficiency at 30% AMB w/w of polymer. The in vivo therapeutic efficacy of oral AMB-NPs was evaluated in neutropenic murine models of disseminated and invasive pulmonary aspergillosis. AMB-NPs exhibited comparable or superior efficacy to that of Ambisome® or Fungizone™ administered parenterally indicating potential of NPs as carrier for oral delivery. Conclusions: The present investigation describes an efficient way of producing AMB-NPs with higher AMB pay-load and entrapment efficiency employing DMSO as solvent and ethanol as non-solvent. The developed oral formulation was highly efficacious in murine models of disseminated aspergillosis as well as an invasive pulmonary aspergillosis, which is refractory to treatment with IP Fungizone™and responds only modestly to AmBisome®

The effect of non-solvent composition on particle size, entrapment efficiency (A) and particle size distribution (B).

<p>PDI, water: 0.3±0.1; 50% ethanol 0.1±0.07; ethanol 0.1±0.02.</p

Lung burden of mice with invasive pulmonary aspergillosis treated with AMB-NPs, AMB deoxycholate, AmBisome and Posaconazole 101 hours post infection (Panel A).

<p>Geometric mean tissue burdens (and standard deviations) of mice with invasive pulmonary aspergillosis treated with AMB-NPs, AMB deoxycholate, AmBisome and Posaconazole 101 hours post infection (<b>Panel B</b>). The p values are from a Kruskal Wallis test (Conover-Inman).</p

Kidney burden of mice with disseminated aspergillosis treated with AMB-NPs, AMB deoxycholate, and Posaconazole 101 hours post infection (Panel A).

<p>Geometric mean tissue burdens (and standard deviations) of mice with disseminated aspergillosis treated with AMB-NPs, AMB deoxycholate, and Posaconazole 101 hours post infection (<b>Panel B</b>). The p values are from a Kruskal Wallis test (Conover-Inman).</p

The effect of solvent composition (DMSO:acetone) on particle size, entrapment efficiency (A) and particle size distribution (B).

<p>For all the preparations, PDI is 0.1±0.01.</p

The effect of initial AMB loading on particle size, entrapment efficiency (A) and particle size distribution (B).

<p>PDI for 10% Loading: 0.1±0.01; 20%: 0.2±0.00; 30%: 0.2±0.01.</p