A randomized, double-blind, Phase 1 study of IN-006, an inhaled antibody treatment for COVID-19

Rationale Although COVID-19 is predominantly a respiratory tract infection, current antibody treatments are administered by systemic dosing. We hypothesize that inhaled delivery of a muco-trapping monoclonal antibody would provide a more effective and convenient treatment for COVID-19. Objective We investigated the safety, tolerability, and pharmacokinetics of IN-006, a reformulation of regdanvimab, an approved intravenous treatment for COVID-19, for nebulized delivery by a handheld nebulizer. Methods A Phase 1 study was conducted in healthy volunteers. Study staff and participants were blinded to treatment assignment, except for pharmacy staff preparing the study drug. The primary outcomes were safety and tolerability. Exploratory outcomes were pharmacokinetic measurements of IN-006 in nasal fluid and serum. Results Twenty-three participants were enrolled and randomized across two single dose and one multiple dose cohorts. There were no serious adverse events (SAEs). All enrolled participants completed the study without treatment interruption or discontinuation. All treatment-emergent adverse events were transient, non-dose dependent, and were graded mild to moderate in severity. Nebulization was well tolerated and completed in a mean of 6 minutes in the high dose group. Mean nasal fluid concentrations of IN-006 in the multiple dose cohort were 921 µg/g of nasal fluid at 30 minutes after dosing and 5.8 µg/g at 22 hours. Mean serum levels in the multiple dose cohort peaked at 0.55 µg/mL at 3 days after the final dose. Conclusions IN-006 was well-tolerated and achieved concentrations in the respiratory tract orders of magnitude above its inhibitory concentration. These data support further clinical development of IN-006. Registration Australian New Zealand Clinical Trials Registry: ACTRN12621001235897