The present invention provides novel derivative of &bgr;-lactam antibiotics, such as meropenem. The inventive compounds include compounds of Formula (I), and pharmaceutically acceptable salts, solvates, hydrates, polymorphs, co-crystals, tautomers, stereoisomers, isotopically labeled derivatives, and prodrugs thereof. Also provided are particles (e.g., nanoparticles) and pharmaceutical compositions thereof that are mucus penetrating. The inventive particles and pharmaceutical compositions may be useful in delivering an inventive compound to the respiratory tract of a subject. The invention further provides methods of using and kits including the inventive compounds, particles thereof, and/or pharmaceutical compositions thereof for treating and/or preventing a pulmonary disease (e.g., a respiratory tract infection).