Abstract 1199P
Background
Immune therapy has brought great treatment successes for patients with cancer. However, it is still difficult to identify the sensitive patients upfront. Target expression (PD-L1) or MSI/MSS status is used for stratification, but these biomarkers not always correlate with treatment efficacy and do not classify the differences between the individual immune therapy drugs. In this study we report patient specific sensitivity to (novel) immune modulatory treatment using our ex-vivo functional testing platform.
Methods
31 patients were included with ovarian, lung or breast carcinoma. Tumor tissue was obtained from metastasis, ascites or pleural fluid. Immune checkpoint inhibitors, STING pathway activators and CSF1R inhibitors were tested as monotherapy or in combination. Drug sensitivity was quantified using high throughput 3D tumor culture, and image analysis using the Ominer® imaging- platform. Fresh or cryopreserved patients tumor tissue was seeded in 384 well plate and exposed with immune drugs. 3D image analysis enabled multiparametric measurement of tumor size reduction and immune cell proliferation.
Results
Ex vivo patient specific sensitivity to Ipilimumab (13/ 31patients), Pembrolizumab (2/31 patients), Nivolumab (1/ 21 patients) and ADU-S100 (8/18 patients) was measured. Our results show the feasibility of testing immune therapy drugs on fresh or cryopreserved tumor tissue derived from resection, biopsy, ascites or pleural fluid. In a higher proportion of lung tumors ex vivo sensitivity was measured compared to ovarian and breast tumors. Clinical trials are currently being initiated to correlate these findings with clinical response of patients treated with immune modulatory drugs. Table: 1199P
Number of patients tested and ex-vivo sensitivity to immune modulatory drugs
| Immune modulatory drug | Patients tested | Ex vivo drug sensitivity |
| Ipilimumab | 31 | 13 |
| Pembrolizumab | 31 | 2 |
| Nivolumab | 21 | 1 |
| ADU-S100 | 18 | 8 |
Conclusions
Ex vivo testing of patients’ tumors shows promise in improving stratification of patients for potentially most effective immune therapy treatments.
Clinical trial identification
CME LUMC - P18.032.
Editorial acknowledgement
Legal entity responsible for the study
LUMC.
Funding
VitroScan BV.
Disclosure
F. Grillet: Full/Part-time employment: VitroScan B.V. C. de Kroon: Advisory/Consultancy: VitroScan B.V. J.R. Kroep: Advisory/Consultancy: VitroScan B.V. J. Overkamp: Full/Part-time employment: OcellO B.V. A. Jariani: Full/Part-time employment: VitroScan B.V. L. Daszkiewicz: Full/Part-time employment: OcellO B.V. K. Yan: Full/Part-time employment: OcellO B.V. D. van der Meer: Full/Part-time employment: VitroScan B.V. L. Price: Shareholder/Stockholder/Stock options, Full/Part-time employment, Officer/Board of Directors: Ocello B.V.; Shareholder/Stockholder/Stock options, Officer/Board of Directors: VitroScan B.V. W. Vader: Leadership role, Shareholder/Stockholder/Stock options, Full/Part-time employment, Officer/Board of Directors: VitroScan B.V.