Combining computational and experimental biology to develop therapeutically valuable IL2 muteins

Area of Science:

• Immunology
• Biotechnology
• Oncology

Background:

• High-dose Interleukin-2 (IL2) was approved in 1992 for advanced renal cell carcinoma and melanoma.
• While IL2 induces durable responses in 5-20% of patients, its use is limited by toxicity and regulatory T cell (Treg) expansion.
• A project initiated in 2005 aimed to rationally design IL2 muteins for cancer therapy with an improved therapeutic index.

Purpose of the Study:

• To uncouple the pleiotropic effects of IL2 on different immune T cells.
• To develop novel IL2 muteins with enhanced therapeutic potential and reduced toxicity.
• To create IL2 variants with improved efficacy in cancer treatment.

Main Methods:

• Utilized a combination of computational and experimental biology approaches.
• Designed and predicted two novel IL2 muteins: no-alpha and no-gamma.
• Evaluated the efficacy and toxicity of IL2 muteins in preclinical models.

Main Results:

• The no-alpha mutein demonstrated higher antitumor activity and lower toxicity than wild-type IL2 in mice.
• The no-gamma mutein showed antitumor activity in mice, likely due to reduced Treg accumulation.
• The no-alpha mutein is advancing to Phase I/II clinical trials for solid tumors.

Conclusions:

• Novel IL2 muteins have been developed with potential for improved cancer therapy.
• The no-alpha mutein represents a potential best-in-class agonist with reduced Treg expansion.
• The no-gamma mutein offers a first-in-class antagonist strategy to inhibit Treg activity.