Oxathiolane Carboxylic Acids for HBV Functional Cure
Solution Overview
Problem
Current treatments for chronic hepatitis B virus (HBV) infection, such as antiviral nucleos(t)ide analogues and Pegylated IFN-α, are limited by long treatment duration, drug resistance, and poor tolerability, with low rates of functional cure, highlighting the need for more effective and tolerable therapeutic options.
Innovation Solution
Development of novel 3-substituted 5-amino-6H-thiazolo[4,5-d]pyrimidine-2,7-dione compounds and their prodrugs with Toll-like receptor agonism activity, specifically targeting TLR7 to activate immune responses and induce antiviral cytokines, offering a potential therapeutic approach for HBV and HCV infections.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If antiviral nucleos(t)ide analogues are used to suppress HBV replication, then viral replication is inhibited, but treatment duration becomes life-long and drug resistance occurs
Solution Approach 1:
The patent applies parameter changes by developing compounds with modified chemical structures (oxathiolane carboxylic acids with specific R1 groups) that alter the pharmacological parameters of TLR7 activation. This enables sustained immune response with shorter treatment duration compared to conventional nucleos(t)ide analogues that require lifelong administration.
Solution Approach 2:
The patent uses TLR7 agonists as intermediary substances that activate the innate immune system to produce antiviral cytokines (IFN-α, IFN-β, IFN-ω). This intermediary mechanism bypasses the need for direct viral replication suppression, enabling functional cure through immune-mediated viral clearance rather than prolonged direct antiviral pressure.
2Reliability
If Pegylated IFN-α is used to induce seroconversion, then immune control is achieved in some patients, but adverse effects make treatment poorly tolerable
Solution Approach 1:
The patent employs small-molecule TLR7 agonists that can be administered orally and have favorable pharmacokinetic profiles, replacing the expensive and poorly tolerable Pegylated IFN-α injections. These small molecules provide the necessary TLR7 activation with better safety and tolerability, reducing harmful adverse effects while maintaining seroconversion potential.
Solution Approach 2:
The patent modifies the pharmacological parameters by using oral TLR7 agonist compounds with optimized bioavailability and reduced immunogenicity compared to Pegylated IFN-α. This changes the delivery and activation parameters, achieving similar or improved clinical outcomes with significantly reduced adverse effects.
3Reliability
If functional cure is pursued with current therapies, then HBsAg seroconversion is achieved in rare cases, but both treatments show very low success rates
Solution Approach 1:
The patent applies preliminary action by activating TLR7 receptors before complete viral clearance occurs, stimulating the innate immune system to produce antiviral cytokines that enhance immune-mediated viral elimination. This preliminary immune activation increases the likelihood of achieving functional cure (HBsAg seroconversion) compared to waiting for natural immune response or relying solely on viral suppression.
Data Source
AI summary
The present invention relates to compounds of formula (I), wherein R1, R2 and R3 are as described herein, and their prodrugs or pharmaceutically acceptable salt, enantiomer or diastereomer thereof, and compositions including the compounds and methods of using the compounds.