6MO - Single-cell analysis of peripheral blood mononuclear cells reveals therapy outcomes are associated with pre-existing immunity in patients treated with oncolytic adenovirus armed with TNF_ and IL2

Background

Engineered oncolytic adenovirus Ad5/3-E2F-d24-hTNFa-IRES-hIL2 (TILT-123) has emerged as a promising candidate for clinical translation due to its ability to induce tumor regression and activate host immunity. The phase 1 clinical trial TUNIMO (NCT04695327) assessed the safety of TILT-123 in patients with advanced solid tumors and provided important insights into its therapeutic activity. The presented study aimed to identify immunological markers in peripheral blood capable of predicting treatment outcomes and to elucidate the mechanisms through which TILT-123 modulates immune responses in patients.

Methods

Single-cell RNA sequencing was performed on peripheral mononuclear cells (PBMCs) from patients at baseline and post-TILT-123 administration on day 64, using the BD Rhapsody platform. Data analysis involved alignment, quantification, and quality control with R, and differential gene expression analysis to identify changes in immune cell composition and activation. The findings were then correlated with available clinical data.

Results

Patients with better outcomes exhibited higher baseline levels of cytotoxic effector cells, such as CD8+ T cells, alongside an increased presence of CD16+ monocytes and a reduced proportion of regulatory T cells, compared to those with poorer outcomes. TCR repertoire analysis revealed greater diversity and clonal persistence in patients with better outcomes, with significant correlations observed between specific TCR profiles at baseline and overall survival. In contrast, patients with poorer outcomes demonstrated impaired NK cell function and reduced inflammatory responses, contributing to a less favorable immune environment. Additionally, TILT-123 treatment enhanced B cell differentiation, promoted the diversification of both B/TCR repertoires, and supported the formation of immunological memory.

Conclusions

Our findings suggest that pre-existing immunity and favorable immune profiles at baseline are associated with better outcomes in response to TILT-123. These results support the potential of personalized treatment strategies to enhance therapeutic efficacy.

Clinical trial identification

NCT04695327.

Legal entity responsible for the study

The authors.

Funding

This study was supported by Doctoral Programme in Clinical Research, University of Helsinki; TILT Biotherapeutics Oy; EU Horizon Grants 811693 and 190121193 (UNLEASHAD and I-CREATE); Jane and Aatos Erkko Foundation; EU Horizon 2020 Research and Innovation Programme under the Marie Skłodowska-Curie Grant agreements (No 813453); HUCH Research Funds (VTR); Cancer Foundation Finland; K. Albin Foundation; Ida Montin Foundation; Sigrid Juselius Foundation and the Finnish Red Cross Blood Service.

Disclosure

J. Clubb: Financial Interests, Personal, Full or part-time Employment: TILT Biotherapeutics Ltd.; Financial Interests, Personal, Stocks/Shares: TILT Biotherapeutics Ltd. D.C.A. Quixabeira: Financial Interests, Institutional, Full or part-time Employment: TILT Biotherapeutics. L. Haybout: Financial Interests, Institutional, Full or part-time Employment: TILT Biotherapeutics Ltd. K. Jalkanen: Financial Interests, Personal, Advisory Board: MSD, Ipsen, Roche, BMS, Pfizer, Lilly, Novartis, Bayer; Financial Interests, Personal, Stocks/Shares: Faron Pharmaceuticals; Financial Interests, Institutional, Local PI, Conduct of sponsored clinical trial: Novartis; Financial Interests, Institutional, Local PI, Sponsored clinical trial: Exelixis; Financial Interests, Institutional, Local PI, Several clinical trials: BMS, MSD, Roche; Financial Interests, Institutional, Local PI, clinical trials: Incyte; Financial Interests, Institutional, Local PI, Conduct of clinical trials: Pfizer; Financial Interests, Institutional, Local PI, Conduct of clinical trial: Bayer; Financial Interests, Institutional, Local PI, Conduct sponsored trial: Orion Pharma. T.V. Alanko: Financial Interests, Personal, Advisory Board: Bristol Myers Squibb, AstraZeneca, MSD, Roche, Servier, AstraZeneca, Incyte, Eisai, Nordic Drugs; Financial Interests, Personal, Invited Speaker: Pfizer; Financial Interests, Personal, Full or part-time Employment: Docrates Cancer Center; Financial Interests, Personal, Stocks/Shares: Docrates Cancer Center; Financial Interests, Institutional, Local PI: AbbVie, Boehringer Ingelheim, Bristol Myers Squibb, TILT Biotherapeutics, Incyte, MSD. R. Havunen: Financial Interests, Institutional, Full or part-time Employment: TILT Biotherapeutics Ltd. S. Sorsa: Financial Interests, Institutional, Full or part-time Employment: TILT Biotherapeutics Ltd. C. Kistler: Financial Interests, Personal, Full or part-time Employment: TILT Biotherapeutics; Financial Interests, Personal, Stocks/Shares, shareholder J. Santos: Financial Interests, Institutional, Full or part-time Employment: TILT Biotherapeutics Ltd.; Financial Interests, Institutional, Stocks/Shares, shareholder: TILT Biotherapeutics Ltd. V. Cervera-Carrascon: Financial Interests, Personal, Full or part-time Employment: TILT Biotherapeutics Ltd; Financial Interests, Personal, Stocks/Shares: TILT Biotherapeutics Ltd. A. Hemminki: Financial Interests, Personal, Full or part-time Employment: TILT Biotherapeutics Ltd.; Financial Interests, Personal, Stocks/Shares: TILT Biotherapeutics Ltd., Circio Holdings ASA. All other authors have declared no conflicts of interest.