Is local ablative stereotactic radiation therapy a valuable rescue strategy for time on drug in patients enrolled in phase I trials?

BACKGROUND

Patients with advanced tumours enrolled in phase I trials display strong treatment expectations and few therapeutic alternatives. When oligo-acquired resistance (≤3 lesions of disease progression; OAR) occurs, local ablative stereotactic radiotherapy (SRT) could allow disease control and continuing the experimental systemic treatment.

PATIENTS AND METHODS

Data from patients enrolled in phase I trials evaluating systemic treatments, who experienced OAR while on the phase I systemic therapy and subsequently received SRT between 01/2014-04/2023 were retrospectively analysed. PFS1 (trial entry to OAR), PFS2 (SRT to first subsequent relapse), time to next systemic treatment (TTNT), and OS were assessed. First subsequent patterns of relapse after SRT were distinguished as OAR2, which could be locally rechallenged, or systemic acquired resistance (>3 lesions of disease progression; SAR). When available, correlations between molecular profile and pathway enrichments of OAR and SAR were explored.

RESULTS

Forty-two patients with 52 oligoprogressive lesions were analysed. The median follow-up was 24 months. SRT allowed a median PFS2 of 7.1 months and a median TTNT of 12.8 months. PFS2 included 49% OAR2 and 51% SAR. Median time to first subsequent relapse (9.6 months vs 3.5 months, P=0.014) and TTNT (22.4 months vs 7.6 months, P<0.001) were longer for OAR2 as compared to SAR. No severe toxicities were reported. A PFS1 <6 months and de novo oligoprogressive lesions associated with the presence of SAR. More diverse enriched gene pathways were observed for SAR as compared to OAR2.

CONCLUSION

In patients enrolled in phase I trials, OAR managed with SRT may increase time on investigational systemic treatments. Predictive factors reflecting tumour aggressiveness and clonal heterogeneity could help deciphering OAR2 from SAR and maximize SRT output in the oligoprogressive setting.

Informations de copyright

Copyright © 2024. Published by Elsevier Inc.

Déclaration de conflit d'intérêts

Declaration of competing interest A.L reports grants for academic research from PharMamar, Beigene, Amgen, Roche and AstraZeneca. As part of the Drug Development Department (DITEP) of Gustave Roussy, C.B. declares being/having: Principal/sub-Investigator of Clinical Trials for Abbvie, Adaptimmune, Adlai Nortye USA Inc, Aduro Biotech, Agios Pharmaceuticals, Amgen, Astra Zeneca Ab, Astra Zeneca, Aveo, Basilea Pharmaceutica International Ltd, Bayer Healthcare Ag, Beigene, BicycleTx Ltd, Blueprint Medicines, Boehringer Ingelheim, Boston Pharmaceuticals, Bristol Myers Squibb, Ca, Casi Pharmaceuticals, Inc, Cato Research, Celgene Corporation, Cellcentric, Chugai Pharmaceutical Co, Cullinan-Apollo, Daiichi Sankyo, Debiopharm, Eisai, Eisai Limited, Eli Lilly, EverImmune, Exelixis, Faron Pharmaceuticals Ltd, Foghorn Therapeutics Inc, Forma Tharapeutics, Gamamabs, Genentech, Genmab, Glaxosmithkline, H3 Biomedicine, Hoffmann La Roche Ag, IGM Biosciences, Imcheck Therapeutics, Incyte Corporation, Innate Pharma, Iris Servier, Iteos Belgium SA, Janssen Cilag, Janssen Research Foundation, Janssen R&D LLC, K-Group Beta, Kinnate Biopharma, Kura Oncology, Kyowa Kirin Pharm. Dev, Lilly France, Loxo Oncology, Medimmune, Menarini Ricerche, Merck Sharp & Dohme Chibret, Merus, Molecular Partners Ag, Nanobiotix, Nektar Therapeutics, Novartis Pharma, Nuvalent, Octimet Oncology Nv, Oncoethix, Oncopeptides, Orion Pharma, Ose Pharma, Pfizer, Pharma Mar, Phio Pharmaceuticals Corp, Pierre Fabre Medicament, Pyramid Bioscience, Regeneron Pharmaceuticals, Relay Therapeutics, Roche, Sanofi Aventis, Seattle Genetics, Sotio A.S, Syros Pharmaceuticals, Taiho Pharma, Tesaro, Transgene S.A, Turning Point Therapeutics, Xencor. Research Grants from Astrazeneca, BMS, Boehringer Ingelheim, Celsius, EIT Philips, GSK, INCA, IDERA, Janssen, Lombard, Merck, MedImmune, Pierre Fabre, Roche, Sanofi, Servier. Non-financial support (drug supplied) from Astrazeneca, BMS, Boringher Ingelheim, GSK, Idera, Medimmune, Merck, NH Theraguix, Roche. All other authors have declared no conflicts of interest.