Development of small molecule drugs targeting immune checkpoints

Area of Science:

• Oncology
• Immunology
• Pharmacology

Background:

• Immune checkpoint inhibitors (ICIs) modulate anti-tumor immunity by targeting co-inhibitory pathways.
• Antibody-based ICIs are widely used but face limitations in efficacy, permeability, and tolerance.
• Small molecule drugs are emerging as promising alternatives with potential to overcome antibody-based ICI limitations.

Purpose of the Study:

• To review the current advancements in small molecule immune checkpoint inhibitors (ICIs).
• To elucidate the mechanisms of action for immune checkpoint proteins targeted by small molecule ICIs.
• To provide a foundation for future research and development in small molecule ICI therapies.

Main Methods:

• Literature review of recent studies on small molecule ICIs.
• Analysis of structural studies on immune checkpoint molecules and chemical inhibitors.
• Examination of ongoing clinical trials investigating synergistic effects of ICIs.

Main Results:

• Small molecule ICIs demonstrate superior oral bioavailability and favorable pharmacokinetic profiles compared to antibodies.
• Recent structural studies have identified new targets and chemical inhibitors for immune checkpoints.
• Clinical trials are exploring combination therapies involving ICIs with immune regulation, anti-angiogenesis, and cell cycle regulation strategies.

Conclusions:

• Small molecule ICIs represent a significant advancement in cancer immunotherapy, offering improved drug properties.
• Understanding the mechanisms of immune checkpoint proteins is crucial for developing effective small molecule inhibitors.
• Further exploration of small molecule ICIs, including combination therapies, holds great promise for cancer treatment.