The invention describes a modified kynureninase enzyme with enhanced catalytic efficiency and stability for therapeutic applications, particularly in cancer treatment. It depletes kynurenine, aiding cancer therapy alone or with other treatments, and can be PEGylated for increased in vivo half-life.
Background
Cancer cells often manipulate metabolic pathways to create a local environment that suppresses immune responses, aiding in their survival and proliferation. One such pathway involves the metabolism of the amino acid tryptophan into kynurenine by the enzymes indoleamine 2,3-dioxygenase (IDO) and tryptophan 2,3-dioxygenase (TDO). Elevated levels of kynurenine in the tumor microenvironment can inhibit the activity of tumor-infiltrating T cells, thereby preventing the immune system from attacking the cancer cells.
Current therapeutic strategies have focused on inhibiting the IDO and TDO enzymes to reduce kynurenine levels. However, these approaches face significant challenges, including the presence of multiple isoforms of IDO and the potential for resistance mechanisms to develop. Additionally, small molecule inhibitors may not effectively target all pathways involved in kynurenine production, and their efficacy can be limited by issues such as poor pharmacokinetics and off-target effects.
Therefore, there is a need for alternative strategies that can more effectively and sustainably reduce kynurenine levels in the tumor microenvironment to enhance anti-tumor immune responses.
Technology description
The technology involves a modified kynureninase enzyme designed to degrade kynurenine, a metabolite involved in various physiological processes, including immune response modulation. The enzyme is engineered with specific amino acid substitutions (e.g., L72N, H102W, A282P, F306W, I331S, and N333T) to enhance its catalytic efficiency and stability in human serum. These modifications result in significantly higher catalytic activity compared to the wild-type enzyme.
The enzyme can be conjugated with polyethylene glycol (PEG) to improve its in vivo half-life, making it suitable for therapeutic applications, particularly in cancer treatment. The technology also includes nucleic acids encoding the modified enzyme, expression vectors, host cells for enzyme production, and pharmaceutical formulations containing the enzyme.
The differentiation of this technology lies in its ability to specifically target and degrade kynurenine with enhanced efficiency and stability. The engineered enzyme exhibits up to 24-fold higher catalytic efficiency compared to the wild-type enzyme, which is crucial for therapeutic applications where sustained enzyme activity is required.
The PEGylation of the enzyme further extends its half-life, allowing for prolonged therapeutic effects with fewer administrations. This makes the modified kynureninase a potent tool for depleting kynurenine in cancer therapy, potentially overcoming the limitations of current treatments that target kynurenine-generating enzymes like IDO and TDO.
The comprehensive approach, including the enzyme, its genetic encoding, production methods, and pharmaceutical formulations, ensures a robust platform for therapeutic intervention in kynurenine-related diseases.
Benefits
- Enhanced catalytic efficiency and stability in human serum
- Significantly higher catalytic activity compared to wild-type enzyme
- Suitable for therapeutic applications, especially in cancer treatment
- Can be used as a standalone treatment or in combination with other anticancer therapies
- Conjugation with polyethylene glycol (PEG) enhances in vivo half-life
- Includes nucleic acids encoding the modified enzyme, expression vectors, and host cells for production
- Pharmaceutical formulations containing the enzyme for therapeutic use
Commercial applications
- Therapeutic enzyme for cancer
- Pharmaceutical formulations
- Gene therapy vectors
- Biotechnological research tools
- Immunotherapy enhancement
Patent link
Issued patent US 11,648,272
