Development of a liver-targeted siRNA delivery platform with a broad therapeutic window utilizing biodegradable...

Area of Science:

• Biomaterials Science
• Drug Delivery Systems
• Molecular Biology

Background:

• Effective in vivo small interfering RNA (siRNA) delivery requires vehicles with high efficacy and a broad therapeutic window.
• Existing polymer platforms often face challenges with toxicity and limited therapeutic margins.

Purpose of the Study:

• To explore structure-activity relationships of a poly(amide) polymer conjugate siRNA delivery platform.
• To optimize polymer parameters for enhanced mRNA knockdown in the liver.
• To evaluate the safety and therapeutic window of the optimized poly(amide) platform.

Main Methods:

• Investigated structure-activity relationships of poly(amide) polymer conjugates for siRNA delivery.
• Assessed mRNA knockdown efficacy in the liver.
• Utilized radiolabeled polymers to study biodistribution, metabolism, and excretion kinetics.
• Determined the therapeutic window by evaluating toxicity at efficacious doses.

Main Results:

• Identified optimized polymer parameters leading to high mRNA knockdown activity in the liver.
• Demonstrated rapid metabolism and clearance of the poly(amide) polymers from the body.
• Achieved significantly lower toxicity and a broader therapeutic window compared to a similar polymer platform.

Conclusions:

• The poly(amide) polymer platform enables efficient in vivo siRNA delivery with favorable pharmacokinetic properties.
• Rapid degradation and clearance contribute to a wide therapeutic window and reduced toxicity.
• This poly(amide)-based platform shows significant promise for the development of human-approved siRNA therapeutics.