Navigating The Development Of Dry Powder For Inhalation

By Beatriz Noriega-Fernandes, Mariam Ibrahim, Rui Cruz, Philip J. Kuehl, and Kimberly B. Shepard

Interest in pulmonary and nasal drug delivery has expanded well beyond respiratory disease, attracting innovators with limited experience in the unique demands of inhalation product development. Yet despite a substantial body of scientific literature, there is no clear, integrated framework that addresses the full arc of decisions from preclinical dose selection through dry powder encapsulation.

This opinion paper from experienced CDMO scientists fills that gap. Written by formulators and researchers with direct industry expertise, it presents a stepwise development strategy anchored in the target product profile, then works through API characterization (small molecule versus biologic), formulation selection (liquid versus dry powder), particle engineering technology choice (jet milling versus spray drying), and the flowability challenges that complicate encapsulation. Decision roadmaps and formulation screening frameworks are included for each major inflection point.

The paper also addresses a largely unresolved issue: the regulatory gap for inhaled biologics, where existing guidance for small molecules or parenteral biologics provides an imperfect reference. For teams evaluating DPI development for the first time, the full paper offers a structured, experience-based perspective worth examining closely.