RNA therapeutics have the potential to revolutionise medicine, but efficient nanotechnology-based strategies are required for their delivery inside cells. The EU-funded RESPIRNA project proposes to repurpose the lung surfactant protein B (SP-B), a key component of pulmonary surfactant, for intracellular RNA delivery. Researchers will investigate the mechanism of action of SP-B and optimise its utilisation for RNA therapeutics. Deliverables will aid the rational design of the next generation of nanocarrier-based RNA formulations capable of crossing cell membranes. Long-term, this will address the unmet medical need for the treatment of many lung diseases.