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Updated: Oct 11, 2025
Analysis of Human T Cell Activity in an Allogeneic Co-Culture Setting of Pre-Treated Tumor Cells
Published on: March 7, 2025
A Novel Approach for Quantifying the Pharmacological Activity of T-Cell Engagers Utilizing In Vitro Time Course
Arthur Van De Vyver1,2, Miro Eigenmann1, Meric Ovacik3
1Roche Pharma Research & Early Development, Pharmaceutical Sciences, Roche Innovation Center Basel, Grenzacherstrasse 124, CH-4070, Basel, Switzerland.
Abstract:
CD3-bispecific antibodies are a new class of immunotherapeutic drugs against cancer. The pharmacological activity of CD3-bispecifics is typically assessed through in vitro assays of cancer cell lines co-cultured with human peripheral blood mononuclear cells (PBMCs). Assay results depend on experimental conditions such as incubation time and the effector-to-target cell ratio, which can hinder robust quantification of pharmacological activity. In order to overcome these limitations, we developed a new, holistic approach for quantification of the in vitro dose-response relationship. Our experimental design integrates a time-independent analysis of the dose-response across different time points as an alternative to the static, "snap-shot" analysis based on a single time point commonly used in dose-response assays. We show that the potency values derived from static in vitro experiments depend on the incubation time, which leads to inconsistent results across multiple assays and compounds. We compared the potency values from the time-independent analysis with a model-based approach. We find comparably accurate potency estimates from the model-based and time-independent analyses and that the time-independent analysis provides a robust quantification of pharmacological activity. This approach may allow for an improved head-to-head comparison of different compounds and test systems and may prove useful for supporting first-in-human dose selection.
Insights
A new time-independent analysis method improves the quantification of CD3-bispecific antibody activity in vitro. This approach offers robust dose-response assessment, overcoming limitations of traditional static assays for cancer immunotherapeutics.
Area of Science:
- Immunology
- Pharmacology
- Biotechnology
Background:
- CD3-bispecific antibodies are emerging immunotherapeutics for cancer treatment.
- In vitro assays using cancer cell lines and peripheral blood mononuclear cells (PBMCs) are standard for assessing their activity.
- Current methods face challenges in robust quantification due to sensitivity to experimental variables like incubation time and cell ratios.
Purpose of the Study:
- To develop a novel, holistic approach for quantifying the in vitro dose-response relationship of CD3-bispecific antibodies.
- To introduce a time-independent analysis method as an alternative to static, single-time-point assays.
- To enhance the reliability and consistency of pharmacological activity assessment.
Main Methods:
- Developed a time-independent analysis integrating dose-response data across multiple time points.
- Compared potency estimates from the time-independent analysis with a model-based approach.
- Evaluated the impact of incubation time on potency values derived from static in vitro experiments.
Main Results:
- Static in vitro potency values are dependent on incubation time, leading to inconsistent results.
- The time-independent analysis provides potency estimates comparable in accuracy to model-based approaches.
- This novel method ensures robust quantification of pharmacological activity for CD3-bispecifics.
Conclusions:
- The time-independent analysis offers a robust method for quantifying CD3-bispecific antibody pharmacological activity in vitro.
- This approach mitigates inconsistencies arising from incubation time variability in traditional assays.
- The method facilitates improved head-to-head compound comparisons and supports first-in-human dose selection.
