Structure-Based Discovery of Potent and Selective Small-Molecule α5β1 Integrin Inhibitors for Asthma Therapy

Area of Science:

• Pharmacology
• Immunology
• Respiratory Medicine

Background:

• Integrin α5β1 is crucial for fibronectin binding in airway smooth muscle (ASM).
• Modulating α5β1 can reduce airway narrowing in asthma models.
• Existing α5β1 inhibitors lack optimal properties for inhaled asthma therapy.

Purpose of the Study:

• To develop potent and selective α5β1 inhibitors for inhaled asthma treatment.
• To identify a lead compound with favorable pharmacokinetic properties for once-daily dosing.

Main Methods:

• Structure-based design and sequential optimization of small molecules.
• In vitro cellular potency and selectivity assays against various integrins.
• In vivo pharmacokinetic studies in rodents following inhalation.

Main Results:

• A series of potent α5β1 inhibitors were identified.
• Lead compound 65 exhibited subnanomolar cellular potency and high selectivity.
• Compound 65 demonstrated favorable rodent pharmacokinetics upon inhalation.

Conclusions:

• Selective α5β1 inhibition via inhalation is a viable therapeutic approach for asthma.
• Compound 65 has potential as a once-daily inhaled asthma therapy.
• Disrupting cellular tethering with α5β1 inhibitors reduces ASM tension.