Oops, you're using an old version of your browser so some of the features on this page may not be displaying properly.

MINIMAL Requirements: Google Chrome 24+Mozilla Firefox 20+Internet Explorer 11Opera 15–18Apple Safari 7SeaMonkey 2.15-2.23

Mini Oral - Gynaecological cancers 2

LBA35 - Phase II study of PARP inhibitor talazoparib and PD-L1 inhibitor avelumab in patients (pts) with microsatellite stable (MSS) recurrent/persistent endometrial cancer


18 Sep 2020


Mini Oral - Gynaecological cancers 2



Tumour Site

Endometrial Cancer


Panagiotis Konstantinopoulos


Annals of Oncology (2020) 31 (suppl_4): S1142-S1215. 10.1016/annonc/annonc325


P.A. Konstantinopoulos1, A.A. Gockley2, N. Xiong1, N. Tayob1, C.N. Krasner1, M. Buss3, S. Campos4, S. Schumer1, A.A. Wright1, J.F. Liu1, M. Shea3, Y. Oladapo5, C. Castro5, M.M. Polak1, C. Whalen1, S. Bouberhan5, S.A. Cannistra3, R.T. Penson5, G. Fleming6, U.A. Matulonis7

Author affiliations

  • 1 Medical Oncology, Dana Farber Cancer Institute, 2215 - Boston/US
  • 2 Obstetrics And Gynecology, Brigham and Women's Hospital, 02115 - Boston/US
  • 3 Medical Oncology, Beth Israel Deaconess Medical Center, 02215 - Boston/US
  • 4 Gynecologic Oncology, Dana Farber Cancer Institute, 02115 - Boston/US
  • 5 Medical Oncology, Massachusetts General Hospital, 02114 - Boston/US
  • 6 Medical Oncology, University of Chicago Department of Medicine - Section of Hematology/Oncology, 60637-1470 - Chicago/US
  • 7 Medical Oncology, Dana Farber Cancer Institute, 02115 - Boston/US


Login to get immediate access to this content.

If you do not have an ESMO account, please create one for free.

Abstract LBA35


Preclinical studies have demonstrated synergistic antitumor activity for combinations of PARP inhibitors (PARPi) with PD-1/PD-L1 inhibitors (PD-1/PD-L1i) which is at least partly mediated by activation of the Stimulator of Interferon Genes (STING) pathway. Given that PD-1/PD-L1i exhibit only modest activity as monotherapy against MSS endometrial cancer (EC), we evaluated whether the combination of the PARPi talazoparib and the PD-L1i avelumab would demonstrate promising activity and acceptable toxicity in that setting.


We conducted a single-arm phase 2 study to evaluate avelumab and talazoparib in recurrent MSS EC (MSS determined by IHC). Eligibility criteria included measurable disease, no limit on prior therapies, and all EC histologies including carcinosarcomas. Co-primary endpoints were objective response rate (ORR) by RECIST 1.1 and progression-free survival rate at 6 months (PFS6). Talazoparib 1mg PO daily and avelumab 10 mg/kg IV every 2 weeks were administered until progression or unacceptable toxicity. A two-stage design was employed to allow for early stopping for futility. In the 1st stage, 16 pts were enrolled; if there were ≥2 ORs or ≥2 PFS6 responses, accrual would continue to the 2nd stage with enrollment of 19 additional pts. Overall, if there were ≥4 ORs or ≥8 PFS6 responses, avelumab+talazoparib would be considered worthy of further study.


As of June, 5th 2020, 35 pts initiated therapy. Three pts exhibited OR [3PRs, ORR 8.6% (95% CI 1.8%-23.1%)] and 8 exhibited PFS6 responses (PFS6 responses by histology: 3 endometrioid, 3 serous, 1 clear cell and 1 carcinosarcoma), 5 ongoing. PFS at 6 months was 25.8% (95% CI 12.4%-41.4%) and median PFS was 3.65 months (95% CI: 2.4-5.4 months). Most common G3+ treatment-related toxicities were anemia (n=16, 45.7%), thrombocytopenia (n=10, 28.6%) and neutropenia (n=4, 11.4%). Seven (20%) pts had dose reductions; no pt discontinued therapy because of toxicity.


Avelumab and talazoparib met the predetermined PFS6 response criterion to be considered worthy of further evaluation in this pt population of recurrent MSS EC. Correlation with biomarkers of response to PARPi and PD-1/PD-L1i is ongoing.

Clinical trial identification


Editorial acknowledgement

Legal entity responsible for the study

Panagiotis Konstantinopoulos.




P.A. Konstantinopoulos: Advisory/Consultancy, Research grant/Funding (institution): AstraZeneca; Advisory/Consultancy, Research grant/Funding (institution): Tesaro/GSK; Advisory/Consultancy, Research grant/Funding (institution): Merck; Advisory/Consultancy, Research grant/Funding (institution): Pfizer; Advisory/Consultancy, Research grant/Funding (institution): Bayer; Advisory/Consultancy: Alkermes; Research grant/Funding (institution): Merck KGaA; Research grant/Funding (institution): Eli Lilly. J.F. Liu: Advisory/Consultancy, Research grant/Funding (institution): Tesaro/GSK; Advisory/Consultancy, Research grant/Funding (institution): Clovis; Advisory/Consultancy, Research grant/Funding (institution): AstraZeneca; Advisory/Consultancy: Merck; Advisory/Consultancy: Genentech; Research grant/Funding (institution): 2X Oncology; Research grant/Funding (institution): Aravive; Research grant/Funding (institution): Arch Oncology; Research grant/Funding (institution): Bristol Myers Squibb; Research grant/Funding (institution): CytoMX Therapeutics; Research grant/Funding (institution): Regeneron; Research grant/Funding (institution): Surface Oncology; Research grant/Funding (institution): Vigeo Therapeutics. R.T. Penson: Advisory/Consultancy, Also participation in DSMB: AbbVie; Advisory/Consultancy, Research grant/Funding (institution), Also participation in DSMB: AstraZeneca; Advisory/Consultancy: Clovis; Advisory/Consultancy, Research grant/Funding (institution): Eisai; Advisory/Consultancy, Research grant/Funding (institution): Genentech; Advisory/Consultancy: Janssen Oncology (J&J); Advisory/Consultancy: Merck & Co; Advisory/Consultancy: NewLink Genetics; Advisory/Consultancy: Pieris Pharma Inc; Advisory/Consultancy: Roche; Advisory/Consultancy: Sutro Biopharma; Advisory/Consultancy: Syndax Pharmaceuticals; Advisory/Consultancy, Research grant/Funding (institution): Tesaro; Advisory/Consultancy, Research grant/Funding (institution): Vascular Biogenics Ltd.; Research grant/Funding (institution): Array BioPharma Inc.; Research grant/Funding (institution): Regeneron; Research grant/Funding (institution): Sanofi-Aventis US Llc. G. Fleming: Honoraria (self): Curio Science; Advisory/Consultancy: GSK; Research grant/Funding (institution), Research IP Supply: Corcept; Research grant/Funding (institution): AbbVie; Research grant/Funding (institution): Roche; Research grant/Funding (institution): Tesaro/GSK; Research grant/Funding (institution): Syndax; Research grant/Funding (institution): 47inc; Research grant/Funding (institution): Iovance; Research grant/Funding (institution): Syros; Research grant/Funding (institution): Astex; Research grant/Funding (institution): Merck; Research grant/Funding (institution): Sanofi; Research grant/Funding (institution): Sermonix; Research grant/Funding (institution): Compugen; Research grant/Funding (institution): Incyte; Research grant/Funding (institution): Eisai. U.A. Matulonis: Advisory/Consultancy: Novartis; Travel/Accommodation/Expenses: AstraZeneca. All other authors have declared no conflicts of interest.

This site uses cookies. Some of these cookies are essential, while others help us improve your experience by providing insights into how the site is being used.

For more detailed information on the cookies we use, please check our Privacy Policy.

Customise settings
  • Necessary cookies enable core functionality. The website cannot function properly without these cookies, and you can only disable them by changing your browser preferences.