Background Treatment options for patients with platinum resistant ovarian cancer [PROC] are limited. Immune checkpoint inhibitors (ICI) have limited activity in PROC, therefore clinical studies evaluating novel therapies are urgently needed. We have previously reported durable and a complete response with COM701 +/- BMS986207 + nivolumab.¹ COM701 is a novel, 1^stin-class ICI binding to PVRIG, that leads to activation of T-cells. BMS-986207 is an ICI of TIGIT. We report longer term follow-up showing continued durable responses in patients with PROC treated with a triple immunotherapy combination blocking the DNAM-1 axis with COM701 + BMS-986207 + nivolumab (NCT04570839).

Methods We enrolled 20 patients with PROC treated with COM701 20 mg/kg + BMS-986207 480 mg + nivolumab 480 mg IV Q4W. Primary objectives were safety/tolerability; secondary objective of preliminary antitumor activity. Key inclusion criteria: Age ≥ 18 yrs, histologically confirmed advanced malignancies and exhausted all available standard treatments. Key exclusion criteria: prior receipt of any inhibitor of PVRIG, TIGIT, or PD-(L)-1. Investigator assessed responses per RECIST v1.1, safety per CTCAE v5.0.

Results No new safety signals are reported. The combination is well tolerated. There were 4/20 [20%] patients with confirmed PR and 5 pts with SD with a DCR [CR+PR+SD] 9/20 [45%], no CRs. Median [med] age 61yr, med number of prior lines of therapy - 4 [range 1–10]. Histology of patients with PR – high grade serous adenocarcinoma [3 pts], clear cell histology [1 pt]. Three pts continue study treatment at 449, 428 and 477 days, 1 pt with high grade serous adenocarcinoma was on study treatment for 222 days.

Conclusions Continued durable confirmed partial responses by blocking the DNAM-1 axis with the combination of COM701 + BMS-986207 + nivolumab in pts with heavily pre-treated PROC. Additional translational data will be presented at the conference. Data extract 06/09/2023.

Acknowledgements We thank the patients for participating in this clinical trial and their families, the investigators and their staff at the clinical trial sites; Study Sponsor Compugen Ltd in collaboration with Bristol Myers Squibb; Danae Hudson, Amanda Harp, Compugen USA Inc for clinical operations oversight of the study

Trial Registration NCT04570839.

Reference

1. Moroney JA, Yeku O, et al. Triple blockade of the DNAM-axis with COM701 + BMS-986207 + nivolumab demonstrates preliminary antitumor activity in patients with platinum resistant OVCA. Annals of Oncology 2022;16(suppl_1):100104–100104. 10.1016/iotech/iotech100104

Ethics Approval The study obtained ethics approval as below:

Salus IRB START2020.15.

WCG IRB 20210109 BSD IRB - University of Chicago IRB20–1549-AM026

Dana Farber OHRS IRB 21–060

John Hopkins OHSR IRB CR00043844/IRB00278513

MD Anderson OHSP IRB 2020–0755

Salus IRB START2020.15

WCG IRB 20210109

All participants gave informed consent before taking part in this study.

Consent Written informed consent was obtained from the patient for publication of this abstract and any accompanying images. A copy of the written consent is available for review by the Editor of this journal.