Anti-Human IL 12/23 (Briakinumab) – Fc Muted™

Research-grade Briakinumab biosimilars are used as calibration standards or reference controls in PK bridging ELISAs by serving as the quantitative benchmark to measure Briakinumab concentrations in serum samples.

In a PK bridging ELISA, calibration standards are prepared by spiking known concentrations of research-grade Briakinumab biosimilar into human serum. These standards form a standard curve, against which the concentrations in unknown serum samples are interpolated. The biosimilar, typically matched in target specificity, isotype, and purity to the originator Briakinumab, ensures assay robustness and accuracy when measuring drug levels in preclinical or clinical samples.

Key procedural details:

• Single Analytical Standard Approach: The current consensus is to use a single PK assay that employs one analytical standard (either the biosimilar or reference Briakinumab) for the quantitation of both biosimilar and reference drug in serum. This minimizes assay variability and eliminates the need for multiple calibration curves.
• Method Validation: The PK assay is validated by preparing standards consisting of research-grade Briakinumab biosimilar in serum at various concentrations (e.g., 50 to 12,800 ng/mL), establishing precision and accuracy. Quality control (QC) samples are also prepared using both the biosimilar and reference product, and all samples are quantified against the biosimilar standard curve.
• Bioanalytical Comparability: Before biosimilars are used as standards, bioanalytical comparability between biosimilar and reference drug is statistically demonstrated (e.g., analytical equivalence assessed by 90% CI within [0.8, 1.25]).
• Application in ELISA: Research-grade biosimilar antibodies may also be employed as capture or detection reagents within the ELISA platform for measuring Briakinumab.

Summary of advantages:

• Decreases inherent assay variability by using a single calibration standard for both originator and biosimilar drugs.
• Facilitates blinded clinical analysis through assay harmonization.
• Ensures high specificity and performance due to research-grade biosimilars' purification, formulation, and matching target profile.

In conclusion, research-grade Briakinumab biosimilars function as key calibration standards or reference controls in PK bridging ELISAs by generating quantifiable standard curves for drug concentration measurement in serum, provided that their bioanalytical equivalence to the reference drug has been rigorously validated.

The primary in vivo models where a research-grade anti-IL-12/IL-23 p40 antibody is administered to study tumor growth inhibition and characterize tumor-infiltrating lymphocytes (TILs) are murine syngeneic tumor models. These models use immunocompetent mice with mouse-derived tumors, allowing for an intact, fully functional immune system and precise analysis of TIL subsets following antibody treatment.

Essential context and supporting details:

• Syngeneic models (such as B16 melanoma in C57BL/6 mice, or MC38 colon carcinoma in C57BL/6 mice) are widely used for these studies because they support full immune interactions between the tumor, host, and administered immunotherapies.

• In such models, administration of agents targeting the IL-12/IL-23 axis—including neutralizing antibodies against IL-12/23p40—allows researchers to study effects on tumor growth and assess immunological changes within the tumor microenvironment, focusing specifically on TIL phenotypes (e.g., CD8^+ T cells, CD4^+ Th1 cells, regulatory T cells, and myeloid populations).

• Studies have reported detailed characterization of TILs following manipulation of the IL-12/IL-23 axis. For example, treatment with IL-12 or modulation via antibodies results in increased proliferation and effector function of CD8^+ T cells, Th1 polarization of CD4^+ T cells, and decreased numbers and suppressive capacity of Tregs, along with pro-inflammatory shifts in myeloid cells.

• Syngeneic models are preferred over humanized models for initial mechanistic studies due to the availability of immune cell markers, genetic knockouts, and well-characterized tumor lines. Humanized mouse models—where human immune cells and tumors are engrafted into immunodeficient mice—are less commonly used for anti-mouse IL-12/23p40 studies, due to species-specific biology of cytokines and antibodies. However, they are considered for studies involving fully human antibodies and translational research.

Additional relevant information:

• Comprehensive characterization of TILs in these studies relies on flow cytometry, single-cell RNA sequencing, and functional assays to identify changes in lymphoid and myeloid compartments after treatment.

• Researchers typically use syngeneic models to evaluate not only tumor growth inhibition, but also modulation of the tumor microenvironment, resistance/sensitivity to checkpoint inhibitors, and combination immunotherapies.

Summary of main models:

• Murine syngeneic tumor models: B16 melanoma, MC38 colon carcinoma, CT26 colon carcinoma, orthotopic glioma models.
• (Less commonly) Humanized mice: Used for translational studies, but less compatible with mouse-specific antibodies targeting IL-12/23p40.

Key markers analyzed:

• CD8^+ effector T cells
• Th1-polarized CD4^+ cells
• Treg populations (FOXP3^+^)
• Myeloid subtypes (M1/M2 macrophages, MDSCs)

Conclusion:
Syngeneic mouse models are the gold standard for administrating research-grade anti-IL-12/IL-23 p40 antibodies to study tumor growth inhibition and TIL characterization due to their robust immunological fidelity and versatility for mechanistic investigation.

Researchers use Briakinumab biosimilar alongside other checkpoint inhibitors, such as anti-CTLA-4 or anti-LAG-3 biosimilars, in preclinical combinations to study potential synergistic effects in immune-oncology models, especially by targeting complementary immune pathways important in cancer immunity.

Briakinumab is a monoclonal antibody directed against the p40 subunit shared by the cytokines IL-12 and IL-23, which play major roles in T cell differentiation and chronic inflammation; it acts by inhibiting these cytokines' signaling and modulating the tumor immune microenvironment. While Briakinumab itself is not a classical checkpoint inhibitor (such as anti-PD-1, anti-CTLA-4, or anti-LAG-3), it has been utilized in research as an immunomodulator with potential to enhance or coordinate with checkpoint blockade.

When combined with checkpoint inhibitors, researchers investigate synergistic effects through mechanisms such as:

• Targeting different stages and locations of T cell activation: For instance, anti-CTLA-4 modulates T cell priming mainly in lymph nodes, while anti-PD-1 or anti-LAG-3 works at the tumor site or in the peripheral tissue.
• Enhancing effector T cell response: Briakinumab may shift T cell differentiation toward a Th1 phenotype and promote cytotoxic T lymphocyte activation by blocking IL-12 and IL-23, which can coordinate with checkpoint inhibitors' ability to unmask antitumor T cell activity.
• Reducing immunosuppressive cell populations: The combined blockade can also diminish populations such as regulatory T cells (Tregs), which are responsible for suppressing immune responses in tumors.
• Overcoming monotherapy resistance: Combinations can help bypass resistance mechanisms that tumors develop against single agents by simultaneously oppressing diverse immune suppressive signals.

Immune-oncology models, usually mouse models with implanted tumors, are used to measure these effects, often by analyzing:

• Tumor growth inhibition or regression
• Changes in intratumoral immune cell composition (CD4+, CD8+ T cells, Tregs, etc.)
• Gene expression or cytokine profile changes
• Survival outcomes

For example, studies with anti-PD-1/CTLA-4 and anti-PD-1/LAG-3 combinations show distinct synergistic mechanisms—anti-PD-1/LAG-3 combinations depend more on CD4+ T cells and reduce Treg activity, while anti-PD-1/CTLA-4 combinations activate cytotoxic CD8+ T cells directly.

Although no specific published models are described for combining Briakinumab directly with checkpoint inhibitors in the current search results, the theoretical and mechanistic rationale—and usage of similar biosimilars for combination research—is well established in immuno-oncology. Tools such as Briakinumab biosimilar enable deeper investigation of how inhibiting the IL-12/23 axis might synergize with checkpoint blockade to promote more effective antitumor immunity.

A Briakinumab biosimilar can be used as the capture or detection reagent in a bridging ADA ELISA by exploiting the bivalent nature of anti-drug antibodies (ADAs) in patient serum, which are antibodies generated by the patient’s immune system in response to the therapeutic drug (Briakinumab or its biosimilar).

In a typical bridging ADA ELISA applied to a biosimilar context:

• Capture Step: The Briakinumab biosimilar is immobilized on a solid phase (e.g., microtiter plate). Blood samples from patients, possibly containing ADAs against Briakinumab, are added. If present, these ADAs will bind to the biosimilar drug on the plate via one of their binding sites.

• Detection Step: The same Briakinumab biosimilar, but now in a labeled form (e.g., conjugated with HRP or biotin), is introduced as the detection reagent. If the patient’s serum contains ADAs, these antibodies will link the capture reagent and the detection reagent by binding to both, effectively “bridging” the two drug molecules. This bridge forms only if anti-drug antibodies that can bind Briakinumab are present. Enzyme-linked detection or color development is then used to quantify the signal, and the amount of signal correlates with the ADA concentration in the sample.

Key technical features:

• The biosimilar is used for both capture and detection to ensure the assay specifically detects antibodies against the biosimilar drug, which is critical given the close molecular similarity between biosimilars and their reference products.
• This format offers high sensitivity and specificity for ADA detection because only antibodies that can bind two molecules of Briakinumab (the biosimilar) will bridge and produce a signal, minimizing background.
• The choice between using a biosimilar or reference product as the reagent depends on assay design and regulatory requirements, but biosimilars are considered scientifically suitable due to their demonstrated similarity to the reference drug.

Contextual application:

• This ADA assay format is used in clinical monitoring of patient immune responses to therapeutic antibodies, including biosimilars such as Briakinumab, to evaluate the risk of loss of efficacy or hypersensitivity reactions due to anti-drug antibodies.

In summation, a Briakinumab biosimilar serves as both the target and detection agent in a bridging ADA ELISA to selectively detect and quantify antibodies generated by patients against this therapeutic, thereby monitoring immunogenicity during clinical use.