# IND-enabling development for IN-003, an inhaled mAb therapy against human metapneumovirus infection

> **NIH NIH R44** · INHALON BIOPHARMA, INC. · 2024 · $1,024,942

## Abstract

Project Summary
 Human metapneumovirus (MPV) is the second leading cause of lower respiratory tract infections
(LRTI) in infants and young children, and a major cause of respiratory illness among the immunocompromised
and the elderly. Unfortunately, there is currently no effective therapy or vaccine for MPV. A pathogen-specific,
safe and effective antiviral would undoubtedly address the current gap in pharmacological interventions.
 MPV, like many common respiratory viruses, spreads in the respiratory tract by shedding progeny (i.e.
daughter) virions back into airway mucus (AM); viruses must then diffuse through AM to reach and infect the
next cell. Thus, the infection remains restricted to the apical side of the airways as it spreads from the upper
respiratory tract to the lower respiratory tract, making it difficult to target by systemically dosed antivirals.
Indeed, while neutralizing monoclonal antibodies (mAbs) offer a safe and likely effective antiviral
intervention, their use is greatly limited by inconvenient dosing and limited distribution into the respiratory tract.
 Inhalon has been advancing a platform of inhaled mAb treatments capable of achieving very high
concentrations of mAb directly in the respiratory tract (i.e. the site of infection) nearly instantly. Specifically, we
have developed methods that enable stable and efficient delivery of mAbs via handheld vibrating mesh
nebulizers, with dosing completed within minutes per day in the comfort of a patient’s own home. Inhalon has
also developed a platform of muco-trapping mAbs, based on tuning sugars on the Fc domain of mAbs that
enable effective crosslinking of virion/mAb complexes to mucins. Muco-trapping mAbs can directly block
progeny viruses from diffusing through AM, and can quickly remove them from the airways by harnessing
natural mucus clearance mechanisms. We have validated our topical mAb therapy approach in hamsters
infected with MPV, as well as in lambs infected with RSV (another virus that, like MPV, propagates exclusively
by apical shedding). Recently, we completed a Phase 1 human clinical study of the safety, tolerability, and
pharmacokinetics of an inhaled mAb against SARS-CoV-2, and found excellent safety and high concentrations
of drug in the airways in humans, despite using a far lower dose compared to typical IV doses.
 Inhalon is advancing IN-003, comprised of a pair of potent neutralizing mAbs against MPV F protein, as
an inhaled mAb therapy against hMPV. By delivering IN-003 directly to the airways, we expect to enable
efficacious and cost-effective treatment for MPV, with limited risk of adverse side effects. In this project, we
seek to produce a GLP tox lot batch of IN-003, and conduct the key GLP IND-enabling studies required by the
FDA before advancing to the clinic. The proposed work, based on our recent regulatory experience advancing
inhaled mAbs for SARS-CoV-2 and RSV, represents the critical path to advance IN-003 into the clinic.
Successful completi...

## Key facts

- **NIH application ID:** 10921913
- **Project number:** 1R44AI181347-01A1
- **Recipient organization:** INHALON BIOPHARMA, INC.
- **Principal Investigator:** JEFF T HUTCHINS
- **Activity code:** R44 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2024
- **Award amount:** $1,024,942
- **Award type:** 1
- **Project period:** 2024-05-15 → 2027-04-30

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10921913

## Citation

> US National Institutes of Health, RePORTER application 10921913, IND-enabling development for IN-003, an inhaled mAb therapy against human metapneumovirus infection (1R44AI181347-01A1). Retrieved via AI Analytics 2026-05-26 from https://api.ai-analytics.org/grant/nih/10921913. Licensed CC0.

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