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
2935 - Correlation of progression free survival-2 and overall survival in solid tumors
Presenter: Paul Mainwaring
Session: Poster Display session 1
Resources:
Abstract
2273 - High performance of serial tumor biopsies in first in human (FIH) phase I trials.
Presenter: Jun Sato
Session: Poster Display session 1
Resources:
Abstract
5933 - Response rates and lesion-level progression patterns of solid tumor patients in an academic phase 1 program: implications for tumor heterogeneity
Presenter: Christopher Chen
Session: Poster Display session 1
Resources:
Abstract
3569 - Clinical Benefit and Response Rate in Early Phase Clinical Trials: First Report from a Single-Institution Study
Presenter: Antonio Marra
Session: Poster Display session 1
Resources:
Abstract
4139 - Patient (pt) selection for immunotherapeutic early-phase clinical trials (ieCTs): a single Phase I Unit experience
Presenter: Matteo Simonelli
Session: Poster Display session 1
Resources:
Abstract
4451 - Improving patient selection for immuno-oncology phase 1 trials: an external validation of five prognostic scores at Claudius Regaud Institute of Toulouse, Oncopôle (IUCT-O).
Presenter: Ghassan Al Darazi
Session: Poster Display session 1
Resources:
Abstract
1696 - Demonstrating the Changing Trends in Phase 1 Clinical Trials
Presenter: Christina Guo
Session: Poster Display session 1
Resources:
Abstract
3202 - Participation of Women in phase 1 oncology clinical trials
Presenter: Laura Vidal
Session: Poster Display session 1
Resources:
Abstract
4518 - Predictors for early trial discontinuation of patients with cancer participating in phase I clinical trials
Presenter: Joeri Douma
Session: Poster Display session 1
Resources:
Abstract
4368 - Safety of Tumor Treating Fields delivery to the torso: Meta analysis from TTFields clinical trials
Presenter: Federica Grosso
Session: Poster Display session 1
Resources:
Abstract