Selective THRβ Agonist Compounds With Reduced Thyroid Axis Inhibition

The invention segments the thyroid hormone receptor into two distinct subtypes (THRα and THRβ) and develops agonists that selectively target only THRβ. This segmentation allows the drug to activate beneficial metabolic pathways in the liver while avoiding unwanted effects on cardiac tissue (THRα) and the thyroid axis, thereby resolving the contradiction between therapeutic efficacy and side effects.

The patent applies local quality by creating compounds with specific molecular structures (e.g., substituted phenyl rings, specific substituent patterns at R1-R6 positions) that confer selective affinity for THRβ over THRα and other receptors. This localized molecular design enables the drug to interact preferentially with the target receptor subtype, achieving effective cholesterol reduction without triggering off-target side effects.

The invention further segments the receptor family by identifying and targeting only the THRβ subtype while explicitly avoiding THRα and THRγ subtypes. The patent demonstrates through in vitro and in vivo studies that the compounds show high selectivity for THRβ with minimal to no activity at other thyroid hormone receptors, thereby preventing both cardiac side effects and thyroid axis inhibition.

The patent introduces structural intermediaries (specific molecular scaffolds with defined substituent patterns) that act as mediators to achieve selective THRβ activation. These intermediary structures serve as the bridge between the desired therapeutic effect and the avoidance of off-target effects, enabling precise receptor subtype targeting.