Pulmatrix is a clinical-stage biopharmaceutical company built around a proprietary inhaled drug delivery platform called iSPERSE, which engineers small, dense, highly dispersible dry powder particles for efficient lung delivery. The platform underpins three drug candidates: PUR3100, an inhaled dry powder formulation of dihydroergotamine for acute migraine; PUR1800, an inhaled kinase inhibitor targeting inflammation-driven COPD exacerbations in steroid-resistant patients; and PUR1900, an inhaled formulation of itraconazole for pulmonary fungal infections. Pulmatrix's business model was to advance these candidates through clinical trials and generate value via licensing, co-development partnerships, or commercialization — and the iSPERSE platform was designed to attract partners as a broadly applicable technology. In practice, the company's most meaningful partnership was with Cipla on PUR1900, where Cipla co-funded development and received ex-U.S. commercialization rights. However, Pulmatrix has effectively ceased operations as a drug developer. As of late 2025, the company has only two employees in administrative roles, has paused all clinical development, and is focused on monetizing or licensing its pipeline rather than advancing it. The company has no marketed products and no commercial revenue. Pulmatrix has entered into a merger agreement with private company Cullgen; if the merger closes, Pulmatrix's existing pipeline would be set aside entirely. If the merger fails, the board has indicated it may pursue dissolution and liquidation.