Anti-Human IL-17A (Secukinumab) [Clone AIN457]

Research-grade Secukinumab biosimilars can be used as calibration standards or reference controls in pharmacokinetic (PK) bridging ELISAs to ensure precise, robust, and comparable quantification of drug concentrations in serum samples, especially during biosimilar development and PK studies.

Key context and methodology:

• Single Analytical Standard: For PK bridging ELISAs supporting biosimilar development, the current industry best practice is to use a single analytical standard, typically the biosimilar (if bioanalytically equivalent to the reference drug), to quantify both biosimilar and reference product concentrations in test samples. This strategy reduces assay variability and eliminates complexities that arise from using multiple standards.

• Establishing Bioanalytical Equivalence: Before deploying a single standard, a rigorous method qualification is performed. Both the biosimilar and reference product are evaluated in the same assay to verify that they yield analytically equivalent results across the concentration range of interest. Precision and accuracy studies, often including multiple lots of each drug, are used to confirm minimal matrix effect and assay comparability.

• Calibration Standards and QC Samples:

  • Calibration (standard) curve: Prepared using the biosimilar (or sometimes reference product) diluted in drug-free serum or matrix, covering a suitable concentration range (e.g., 50–12,800 ng/mL).
  • Reference controls: Quality control (QC) samples are typically prepared using both the biosimilar and reference drug to validate the method and ensure assay performance across multiple runs.

• Assay Procedure: Serum samples from PK studies are run alongside the calibration standards. The drug concentration in unknown samples is interpolated from the standard curve generated from the biosimilar reference material.

• Validation and Regulatory Consideration: The ELISA (ligand-binding assay) must be validated to demonstrate equally robust quantification of both the biosimilar and the reference product according to regulatory guidelines.

• Why bridging ELISA?: This "bridging" approach is crucial for comparing PK properties of biosimilars and innovator drugs in clinical studies, demonstrating that analytical and clinical equivalence is due to the drug, not assay artifacts.

Summary table: Use of Secukinumab Biosimilar as Calibration/Reference in PK Bridging ELISA

References:

• A single PK assay using a single analytical standard (often biosimilar) is recommended for robust PK comparisons.
• Validation involves accuracy, precision, and comparability checks with both biosimilar and reference materials.

This approach aligns with regulatory and industry standards and is essential for reliable PK bridging studies of secukinumab biosimilars.

Based on the available research, syngeneic mouse models are the primary experimental systems used to study tumor growth inhibition and characterize tumor-infiltrating lymphocytes (TILs) following anti-IL-17A antibody administration.

Syngeneic Mouse Models

Non-Small Cell Lung Cancer (NSCLC) ModelThe LLC (Lewis Lung Carcinoma) syngeneic model in C57BL/6 mice has been extensively used to study anti-IL-17A therapy effects. In this model, LLC cells are inoculated subcutaneously, and mice receive anti-IL-17A monoclonal antibody treatments on days 6, 9, 12, and 15 post-inoculation. This model demonstrated that IL-17A blockade reduced tumor size and weight while significantly decreasing PD-L1 expression in tumor tissues.

Breast Cancer ModelThe EO771 syngeneic breast cancer model represents another well-characterized system for anti-IL-17A studies. Mice are challenged with 1 × 10^6 syngeneic EO771 tumor cells and treated with anti-IL-17A antibody four times at weekly intervals starting 7 days post-inoculation. This model showed significant tumor burden reduction with anti-IL-17A treatment and demonstrated decreased PDL1 expression in the tumor microenvironment along with reduced Treg cell percentages in tumor tissues.

Melanoma ModelsMultiple syngeneic melanoma models have been employed, including the B16-F10 model in various mouse backgrounds. The MT/ret-derived primary cutaneous melanoma model has been particularly useful for studying IL-17A's role in immune checkpoint inhibitor efficacy. Additionally, B16F10 xenograft models in Foxp3 DTR mice have been used to investigate IL-17A's effects on CD8 T cell exhaustion.

Colorectal Cancer ModelsSeveral syngeneic colorectal cancer models have been utilized, including the AOM-DSS-induced colitis-associated cancer (CAC) model, where IL-17A neutralization through antibody treatment inhibited tumor development. The CPC-APC mouse model, which more accurately represents human colorectal cancer, has also been employed to study IL-17RA signaling effects on colon tumor development.

TIL Characterization Findings

These syngeneic models have revealed important insights about TIL populations following anti-IL-17A treatment:

• Enhanced CD8+ T cell responses with improved antitumor immunity
• Decreased regulatory T cell (Treg) populations in tumor tissues
• Altered neutrophil infiltration patterns within the tumor microenvironment
• Changes in overall immune infiltration that create either favorable or unfavorable conditions depending on the cancer type

Combination Therapy Studies

Many of these syngeneic models have been used to study combination approaches, particularly anti-IL-17A with anti-PD-1/PD-L1 therapies. The EO771 model demonstrated that combined IL-17A and PDL1 antibody treatment significantly increased survival rates compared to single-agent treatments. However, some models like the LLC system showed that anti-IL-17A combination therapy was inferior to anti-PD-L1 monotherapy, highlighting the complex relationship between IL-17A signaling and immune checkpoint function.

These syngeneic models remain the gold standard for anti-IL-17A antibody research because they preserve intact immune systems while allowing for detailed characterization of both tumor growth kinetics and immune cell infiltration patterns.

Based on the available research, there is currently limited direct evidence of researchers specifically combining secukinumab biosimilars with checkpoint inhibitors like anti-CTLA-4 or anti-LAG-3 biosimilars in immune-oncology models. However, the search results reveal important foundational work and combination strategies that provide insight into this emerging area.

Current Research on Secukinumab Biosimilars

Researchers have developed innovative approaches to secukinumab biosimilar production and delivery. A novel lentivirus-based gene therapy strategy has been developed that enables the expression of biosimilar secukinumab directly within patient cells. This approach uses human chorionic villous mesenchymal stem cells (CMSCs) as cellular vehicles to produce secukinumab, achieving production levels of 30-40 µg/ml, which is comparable to traditional CHO cell production systems.

The gene therapy approach offers several advantages for combination studies, including the ability to provide sustained, localized antibody production and the potential for temporal control over therapeutic protein expression. This delivery method could theoretically be adapted for combination therapies, though specific studies combining secukinumab with checkpoint inhibitors have not been documented in the current literature.

Checkpoint Inhibitor Combination Strategies

Research in immune-oncology has extensively explored multi-checkpoint inhibitor combinations, particularly focusing on the synergistic effects of targeting different immune pathways simultaneously. The rationale behind these combinations is based on their distinct mechanisms of action:

Anti-CTLA-4 antibodies primarily function in the lymph node compartment, restoring the induction and proliferation of activated T cells, while anti-PD-1/PD-L1 inhibitors act at the tumor periphery, preventing the neutralization of cytotoxic T cells by PD-L1 expressing tumor and immune cells in the tumor microenvironment.

Clinical evidence from trials like CheckMate 067 has demonstrated that combination checkpoint inhibitor therapy can provide superior outcomes in specific patient populations, particularly those with PD-L1-negative tumors, where ipilimumab plus nivolumab achieved longer progression-free survival (11.2 months) compared to nivolumab alone (5.3 months).

Potential for Future Combination Studies

While direct evidence of secukinumab biosimilar combinations with checkpoint inhibitors is lacking, the pharmacokinetic equivalence demonstrated by secukinumab biosimilars like CMAB015 provides a foundation for such studies. The biosimilar showed geometric mean ratios of 104.05% for Cmax and 95.70% for AUC compared to reference secukinumab, with confidence intervals within bioequivalence limits.

The development of gene therapy-based biosimilar delivery systems could potentially enable researchers to study complex multi-drug combinations by engineering cells to express multiple therapeutic antibodies simultaneously. This approach could overcome some of the manufacturing and cost challenges associated with producing multiple biosimilar antibodies for combination studies.

Research Gap and Future Directions

The current literature reveals a significant research gap in the specific area of combining secukinumab biosimilars with checkpoint inhibitors. Given that secukinumab targets IL-17, which plays a role in inflammation and immune regulation, there may be theoretical basis for studying its interaction with checkpoint inhibitors in tumor microenvironments where inflammatory and immune checkpoint pathways interact.

Future research in this area would likely need to establish appropriate preclinical models that can adequately represent the complex interactions between IL-17 inhibition and checkpoint inhibitor mechanisms, particularly in cancers where both inflammatory and immune checkpoint pathways are relevant to disease progression and treatment response.

A Secukinumab biosimilar can be used as both the capture and detection reagent in a bridging anti-drug antibody (ADA) ELISA to detect patient antibodies raised against the therapeutic drug.

In a typical bridging ADA ELISA:

• The biosimilar (e.g., biotinylated Secukinumab biosimilar) is immobilized on a plate (either directly or via a streptavidin-biotin system).
• Patient serum is added; if anti-Secukinumab antibodies (ADA) are present, they bind to the immobilized biosimilar.
• The same Secukinumab biosimilar, conjugated with a detection label (such as HRP), is then added. This binds to another site (the other "arm") of any ADAs bound to the immobilized biosimilar, forming a "bridge" between the capture and detection reagents.

This format is highly specific and sensitive for the detection of bivalent ADAs (typically IgG), as only antibodies that can bind to two molecules of the drug (the biosimilar) will be detected, reducing non-specific signals.

Key points regarding the use of a biosimilar in this context:

• The biosimilar must be structurally and functionally similar to originator Secukinumab so that it will bind ADAs generated against either product.
• Using a biosimilar as the assay reagent can be cost-effective and ensures broad ADA detection, as patient antibodies are generally raised against conserved epitopes present on both originator and biosimilar.
• Both the capture (biotinylated or plate-bound) and detection reagent (enzyme- or dye-labeled) must be validated to ensure equivalent performance with patient samples—particularly important in clinical trials or comparisons between originator and biosimilar.

Technical workflow summary:

1. Coat well with biosimilar Secukinumab (biotinylated, using streptavidin-coated plates, or directly adsorbed).
2. Add patient serum — any existing anti-Secukinumab antibodies bridge between immobilized and labeled biosimilar.
3. Add enzyme-labeled biosimilar for detection.
4. Signal readout reflects ADA concentration in the patient sample.

This approach is standard for immunogenicity testing of monoclonal antibodies, including biosimilars and originator products, enabling monitoring of the patient's immune response to therapy.