First-in-class humanized FSH blocking antibody targets bone and fat

Area of Science:

• Endocrinology and Reproductive Biology
• Immunology and Therapeutics

Background:

• Follicle-stimulating hormone (FSH) plays a role in regulating body fat, cholesterol levels, and bone mass.
• Genetic or pharmacological blockade of FSH in mice has demonstrated positive effects on these metabolic and skeletal parameters.
• These findings suggest that targeting FSH could offer a therapeutic strategy for obesity, hypercholesterolemia, and osteoporosis.

Purpose of the Study:

• To develop and characterize a novel, fully humanized antibody capable of blocking FSH activity.
• To investigate the binding mechanism and functional consequences of this FSH-blocking antibody.

Main Methods:

• Generation of a first-in-class, fully humanized, epitope-specific FSH blocking antibody.
• Structural and functional analyses including protein thermal shift, molecular dynamics, and fine mapping of the FSH-FSH receptor interface.
• Assessment of antibody binding affinity (K_D of 7 nM) and its effect on FSH receptor interaction.

Main Results:

• The humanized antibody demonstrated stable binding to key residues (two of five) at the FSHβ subunit-receptor interface.
• This binding was sufficient to effectively block the interaction between FSH and its receptor.
• The antibody profoundly inhibited FSH action in cell-based assays.

Conclusions:

• A novel, fully humanized antibody has been developed that specifically blocks FSH action by interfering with receptor binding.
• This antibody represents a promising first-in-class therapeutic candidate for obesity, hypercholesterolemia, and osteoporosis.
• Further preclinical and clinical testing is warranted to evaluate its therapeutic potential.