Abstract 3184
Background
REG is an active drug in non-adipocytic soft tissue sarcoma previously treated with doxorubicin (Mir et al. Lancet Oncol 2016). Efficacy of REG in PAZ pretreated pts is unknown. REGOSARC is a multi-cohort double-blind placebo (PLAC)-controlled phase II trial assessing the activity of REG in soft-tissue sarcoma previously treated with doxorubicin. Cross-over after centrally confirmed disease progression was allowed.
Methods
In the present subgroup analyses of the pooled study (cohorts B,C,D and E), we analyzed the magnitude of REG activity in pts with prior exposure to PAZ.
Results
The total study population consisted of 176 pts (101 women, 57%), with a median age of 59 (20-81). with the following histologies (n/%): leiomyosarcoma (80/45), synovial sarcoma (28/16) or other sarcoma (68/39). Most pts had PS = 0 (N = 83, 47%) or PS = 1 (N = 92, 52%). Median time from initial diagnosis to study enrollment was 30 months (range, 5.6-498). Median follow-up was 59.6 months. 88 pts each were allocated to the REG and placebo (PLAC) arms, including 21 (24%) and 22 (25%) pts with previous PAZ exposure. Overall, the significant benefit of REG compared to PLAC in terms of PFS with a median PFS of 3.8 (REG) vs 1.0 months (PLAC); HR(REG/PLAC)=0.43 [95%CI: 0.32-0.59], p<.00001, was confirmed. The magnitude of the benefit did not significantly differ when assessed by prior PAZ exposure: HR(REG/PLAC)=0.33 [0.18-0.61] for those previously exposed to PAZ and 0.45 [0.32-0.65] for those not exposed to PAZ; interaction test in Cox model, p = 0.35. In the total study population non significant numerically higher median OS was observed in the REG arm:13.4 (REG) vs 9.0 months (PLAC), HR = 0.76 [0.56-1.03], p = 0.08. The magnitude of this difference was larger in pts previously exposed to PAZ: HR(REG/PLAC)=0.43 [0.22-0.85] (p = 0.015), vs HR = 0.88 [0.62-1.25] (p = 0.49) for those not exposed to PAZ; interaction test, p = 0.065. Safety has been previously reported (Mir et al. Lancet Oncol 2016; Penel ASCO 2019).
Conclusions
We conclude that prior exposure to PAZ did not significantly modify PFS advantage of REG. Benefit of REG in terms of OS could be larger in patients previously exposed to PAZ.
Clinical trial identification
NCT01900743.
Editorial acknowledgement
Legal entity responsible for the study
Centre Oscar Lambret, Lille, France.
Funding
Bayer.
Disclosure
All authors have declared no conflicts of interest.
Resources from the same session
3690 - PD-L1 expression in resected undifferentiated pleomorphic sarcoma and its clinical implications
Presenter: Kyoungmin Lee
Session: Poster Display session 1
Resources:
Abstract
2013 - PD-L1 expression as a potential therapeutic target and prognostic biomarker in well-differentiated and dedifferentiated liposarcoma.
Presenter: Heejung Chae
Session: Poster Display session 1
Resources:
Abstract
5021 - Soft tissue sarcomas express a distinct mRNA immune profile
Presenter: Viktor Grünwald
Session: Poster Display session 1
Resources:
Abstract
3029 - The molecular landscape of fusion genes in endometrial stromal sarcomas include three nosological entities with different natural history
Presenter: Mehdi Brahmi
Session: Poster Display session 1
Resources:
Abstract
3914 - Clinical validation of a novel assay for the detection of diagnostic alterations in sarcomas
Presenter: Lauren Mc Connell
Session: Poster Display session 1
Resources:
Abstract
1912 - A prospective correlative trial of personalized patient-derived xenograft (PDX) as avatars for drug therapy in patients with metastatic or recurrent soft tissue sarcomas (STS).
Presenter: Kanan Alshammari
Session: Poster Display session 1
Resources:
Abstract
5097 - Fusion of immortalized myoblasts induces genomic instability that drives tumor development and progression.
Presenter: Candice Merle
Session: Poster Display session 1
Resources:
Abstract
1383 - let-7a suppress Ewing sarcoma CSCs' malignant phenotype through forms a positive feedback regulation loop with lin28 via STAT3
Presenter: Xu Jiang
Session: Poster Display session 1
Resources:
Abstract
3386 - Myoepithelial Tumors of Soft Tissues and Extraskeletal Myxoid Chondrosarcomas feature a distinct transcriptional pattern
Presenter: Dominga Racanelli
Session: Poster Display session 1
Resources:
Abstract
1844 - In Vivo Efficacy and Enhanced Tumor Accumulation of Liposomal Vinorelbine (TLC178) in Human Sarcoma Xenograft Mice Model
Presenter: Wan-ni Yu
Session: Poster Display session 1
Resources:
Abstract