Virtual Library
Start Your Search
M. Provencio
Author of
-
+
P3.01 - Advanced NSCLC (ID 621)
- Event: WCLC 2017
- Type: Poster Session with Presenters Present
- Track: Advanced NSCLC
- Presentations: 2
- Moderators:
- Coordinates: 10/18/2017, 09:30 - 16:00, Exhibit Hall (Hall B + C)
-
+
P3.01-005 - ASTRIS: A Real World Study of Osimertinib Treatment in Patients with EGFR T790M Positive Advanced NSCLC; Interim Analysis (ID 7884)
09:30 - 09:30 | Author(s): M. Provencio
- Abstract
Background:
Osimertinib is a third-generation, CNS active EGFR-TKI that potently and selectively inhibits both EGFR-sensitizing and EGFR T790M resistance mutations in non-small cell lung cancer (NSCLC). We report interim clinical and molecular diagnostic testing results from a predefined interim analysis of the ongoing ASTRIS study (NCT02474355).
Method:
Patients (pts) received osimertinib 80 mg once daily. Eligible pts had advanced NSCLC that had progressed on prior EGFR-TKI therapy and with a T790M mutation determined by local validated molecular test, WHO performance status (PS) 0−2, acceptable organ and bone marrow function and no history of interstitial lung disease or QTc prolongation. Asymptomatic, stable CNS metastases were permitted. The primary efficacy outcome was overall survival; other outcomes included local test methods, specimen type, EGFR mutations identified, investigator-assessed response rate (RR), progression-free survival and time to treatment discontinuation. Safety data are also reported.
Result:
From 18 Sept 2015 to the planned 3 Nov 2016 data cut-off (DCO), 1217 pts received osimertinib 80 mg once-daily across 14 countries with a median age 64 yrs (27–92 yrs), 67% female, 61% White, 37% Asian, 87% WHO PS 0/1, 44% prior chemotherapy, 45% prior radiotherapy. All pts tested positive for T790M; T790M was reported alone in 185 pts (15%). The most common testing methods were PNA-Clamp 317 pts (27%), Qiagen therascreen 254 pts (22%), and Roche cobas 204 pts (17%). Exon 19 deletion was the most common co-occurring mutation with T790M (57%), followed by L858R (27%). Tissue or cytology specimens were used in 720 pts (59%), plasma in 433 pts (36%), and other specimens in 64 pts (5%). At DCO, the median duration of exposure was 3.8 months (<1–13.2 months) with a median follow-up time of 4.1 months (<1−14 months). In pts evaluable for response, the investigator-assessed RR was 64% (569/886; 95% CI 61, 67). Adverse events (AEs) leading to dose modification and treatment discontinuation were reported in 122 pts (10%) and 54 pts (4%), respectively. Serious AEs were reported in 165 pts (14%) and AEs leading to death in 28 pts (2%).
Conclusion:
ASTRIS is the largest reported global study of osimertinib in pts with T790M-positive NSCLC identified by a wide array of molecular testing methods and from various specimen types. Considering this breadth of T790M testing, the clinical activity of osimertinib is like that observed in the clinical trial program and no new safety signals were identified.
-
+
P3.01-073 - TPX-0005 with an EGFR Tyrosine Kinase Inhibitor (TKI) Overcomes Innate Resistance in EGFR Mutant NSCLC (ID 8956)
09:30 - 09:30 | Author(s): M. Provencio
- Abstract
Background:
Overexpression of several receptor tyrosine kinases (RTKs) substitutes EGFR signaling in EGFR-mutant NSCLC. The MET ligand hepatocyte growth factor (HGF) provides an alternative signaling mechanism for EGFR by inducing inter-receptor cross talk with EphA2, CUB domain-containing protein-1 (CDCP1) or AXL. SHP2, a non-receptor protein tyrosine phosphatase is central in signal transduction downstream of RTK signaling and in Src activation. We previously demonstrated that STAT3 and Src-YAP1 signaling limits EGFR TKI efficacy in EGFR-mutant NSCLC. We are now exploring the possibility of multiple RTK activation through a Src-YAP1-mediated transcriptional program. We are evaluating whether combined EGFR inhibition with TPX-0005, a novel orally available multikinase inhibitor and potent Src/FAK and JAK2 inhibitor, can be more efficient than EGFR inhibition alone in EGFR-mutant NSCLC cells.
Method:
We studied the mRNA expression levels of stromal HGF and tumor RTKs, AXL, CDCP1, MET, and EphA2, as well as SHP2, and clinical outcome in baseline samples of 64 EGFR-mutant NSCLC patients treated with first-line EGFR TKI. We combined in vitro approaches to explore whether gefitinib or osimertinib combined with TPX-0005 can abolish STAT3 and Src-YAP1 and downregulate the expression of RTKs.
Result:
High levels of AXL, CDCP1 and SHP2 mRNA expression were associated with worse outcome to EGFR TKI in 64 EGFR-mutant NSCLC patients. Median progression-free survival (PFS) was 14.5 and 23.4 months for patients with high and low AXL mRNA, respectively (p=0.0359). Median PFS was 9.1 and 20.2 months for patients with high and low CDCP1 mRNA, respectively (p=0.0179). Tumoral EPHA2 and MET or stromal HGF levels did not affect PFS. Median PFS was 11.4 and 24.1 months for patients with high and low SHP2 mRNA, respectively (p=0.0094). The combination of gefitinib/osimertinib with TPX-0005 resulted in highly synergistic suppression of cell viability and reduced colony formation in two EGFR-mutant cell lines. The combination abolished the EGFR inhibition-induced STAT3 and YAP1 phosphorylation, as confirmed by western blotting and immunofluorescence. The results of TaqMan quantitative-PCR assay revealed that gefitinib/osimertinib plus TPX-0005 reduced the mRNA levels of AXL, CDCP1 and MET, an effect that could not be obtained with EGFR inhibition alone. In vivo experiments are ongoing.
Conclusion:
AXL and CDCP1 are adverse predictive markers of PFS in EGFR-mutant NSCLC patients. STAT3 and Src-YAP1 signaling limits the efficacy EGFR TKI. Combined EGFR inhibition with TPX-0005 (currently in phase I clinical testing) is a particularly attractive strategy