COVID-19(43) Treatment(32) SARS-CoV-2(25) approach(21) coronavirus(21) drug(20) lung(20) administration(19) Concentration(18) Antiviral(15) effective(15) COVID-19 pandemic(14) Lungs(13) required(13) Protein(13) Infection(12) Remdesivir(12) injection(11) Administered(11) mice(11) analyzed(10) evaluated(10) therapeutic(10) IMPROVE(10) provided(10) was used(10) pharmacokinetics(9) PLGA(9) Inhaled(9) investigated(9)