Delivering chemotherapy directly to the lung using inhalation, combined with nanotechnology, aims to increase local drug exposure while reducing systemic off-target distribution. This study evaluated an inhalable paclitaxel (PTX) nanoagglomerate powder (PTX-NADP) as a proof-of-concept platform for lung cancer chemotherapy and established a biorelevant in vitro model to screen inhalable formulations.
The authors developed an air-liquid interface (ALI) lung cancer organoid (LCO) culture intended to recapitulate key features of lung tumors for biorelevant antitumor efficacy screening. The ALI format was used to assess aerosolized formulations directly at a physiologically relevant interface, providing a novel new approach methodology (NAM) platform for inhalable chemotherapy evaluation.
The study focused on a nanoagglomerate powder formulation of paclitaxel (PTX-NADP) designed for aerosolization and pulmonary delivery. PTX-NADP could be reconstituted into nanosuspensions for intratracheal (IT) instillation in animal studies. The abstract reports aerosolized PTX-NADP was evaluated in vitro and translated to in vivo biodistribution and efficacy experiments; detailed physicochemical characterization and aerosol performance metrics are described in the full article (not detailed in the abstract).
Aerosolized PTX-NADP demonstrated dose-dependent antitumor activity in ALI FA34-O LCO cultures and outperformed raw PTX powder under the same testing conditions. These results indicate that the nanoagglomerate formulation improved in vitro efficacy in a model intended to better reflect the lung tumor microenvironment compared with non-formulated drug powder.
In vivo biodistribution studies compared pulmonary delivery by intratracheal (IT) instillation of PTX nanosuspensions reconstituted from PTX-NADP with systemic delivery by intravenous (IV) injection. IT administration resulted in enhanced pulmonary PTX concentrations and reduced off-target tissue distribution relative to IV injection, supporting the concept that inhaled nanosuspensions can increase local lung exposure while limiting systemic distribution.
In an orthotopic lung adenocarcinoma mouse model, IT delivery of reconstituted PTX nanosuspensions was reported to be well tolerated. IT administration achieved numerically similar tumor growth suppression (approximately 67%) compared with IV injection despite lower cumulative doses, indicating that locally delivered PTX via the nanoagglomerate approach can produce antitumor effects comparable to systemic therapy at reduced total drug exposure.
The study observed that a higher proportion of mice receiving combined IT and IV treatment exhibited reduced tumor burden compared with either route alone. This finding suggests that pairing inhaled nanoparticle-based chemotherapy with systemic administration could enable therapeutic intensification, although the abstract does not provide specific proportions, statistical comparisons, or detailed regimen information.
The results support the therapeutic potential of PTX-NADP-enabled inhaled PTX nanoparticle delivery as a convenient option to improve lung cancer treatment outcomes by enhancing lung drug exposure and limiting off-target distribution. Additionally, the ALI LCO culture model shows promise as a biorelevant screening platform (a NAM) for inhalable chemotherapy formulations, potentially accelerating preclinical selection of inhaled anticancer candidates.
The abstract summarizes primary findings but does not report specific quantitative biodistribution values, dosing regimens, group sizes, statistical analyses, or detailed safety/toxicity endpoints; these methodological and numerical details are contained in the full text and are not reported in the abstract. Likewise, exact comparative statistics for the combined IT and IV arms were not provided in the abstract.
A nanoagglomerate powder formulation of paclitaxel (PTX-NADP) demonstrated dose-dependent in vitro efficacy in an ALI lung cancer organoid model and improved pulmonary drug delivery with reduced off-target distribution in vivo. Intratracheally delivered PTX nanosuspensions reconstituted from PTX-NADP suppressed orthotopic lung tumor growth to a similar degree as IV administration (~67% suppression) at lower cumulative doses, and combined local and systemic dosing produced more frequent reductions in tumor burden. The study supports further investigation of inhaled nanoparticle-based chemotherapy and the use of ALI LCO models for biorelevant formulation screening.