Formulation, In Vitro And In-Vivo Analysis Of A Spray-Dried Topotecan Inhalation Powder  

Michael Burke¹, Devon Dubose¹, David Lyon¹, Ramesh Chand², Mathewos Tessema², & Philip Kuehl²

¹Capsgel, a Lonza Company, 64550 Research Rd, Bend, OR, 97701, USA

² Lovelace Biomedical, 2425 Ridgecrest Drive. SE, Albuquerque, NM, 87108, USA,

Summary

In this presented study we detail a spray dried formulation, which contains; Topotecan, Trehalose and Leucine for it’s in vivo efficacy. Topotecan is chemotherapeutic agent that is primarily used for the treatment of small cell lung cancer. By using the spray drying process a stable and aersolizable dry powder can be directly delivered to the lung to limit off-site toxicity. The dry powder for inhalation was designed, developed and evaluated by in vitro characterization. The material was confirmed to have a pulmonary particle size of 2.92 µm and exhibited appropriate physico-chemical properties. Following development, dry powder was then aerosolized and evaluated in a non-clinical rodent pharmacokinetic study to quantify local drug concentrations at the site of action. The in vivo results suggested that when using the current marketed oral dose and applying it to a pulmonary delivery, the lung tissue retention was increased by a factor of 30. In addition, the total systemic exposure was significantly reduced. Therefore, the actual dose that could be used for expected efficacy could be up to 30 fold lower when delivered via inhalation. The designed formulation may allow for targeted treatment of lung cancer while reducing off-target side effects.