First results from the randomised ENGOT-OV56/NSGO-CTU-DOVACC trial investigating olaparib (ola), durvalumab (durva) and UV1 vaccination as maintenance therapy for patients (pts) with BRCA-wildtype (wt) recurrent ovarian cancer (ROC)

DOVACC

Patient / Population Intervention / Exposure Comparison Outcome

In patients with BRCA-wildtype recurrent ovarian cancer, adding UV1 vaccination to olaparib plus durvalumab maintenance did not significantly improve progression-free survival compared with olaparib alone.

N

188patients

Design

Open-label randomised phase 2 trial allocating 188 patients with non-germline BRCA-mutated or tumour BRCA-wildtype recurrent ovarian cancer, without progression on or after their most recent platinum-based regimen after 2-3 prior lines of chemotherapy, 1:1:2 to maintenance olaparib (Arm A), olaparib plus durvalumab (Arm B) or olaparib plus durvalumab plus the hTERT-directed vaccine UV1 (Arm C), stratified by HRD status and prior PARP inhibitor (EU Clinical Trials Register 2024-516327-14-00, EudraCT 2020-004738-39).

Endpoint

Progression-free survival in Arm C (olaparib plus durvalumab plus UV1) vs Arm A (olaparib).

ResultMedian PFS with olaparib plus durvalumab plus UV1 8.7 mo (95% CI 6.1-11.3) vs 5.9 mo (95% CI 5.3-8.2) with olaparib alone (HR 0.83, 95% CI 0.68-1.01; p=0.066), with 64/94 (68%) vs 34/46 (74%) PFS events. Post hoc restricted mean survival time difference at 22 mo was 2.5 mo (95% CI 0.1-4.9; exploratory p=0.043). PFS HR for Arm C vs olaparib plus durvalumab 0.77 (95% CI 0.51-1.14). Subgroup HRs for Arm C vs Arm A: HRD-negative 0.73 (0.58-0.92), HRD-positive 1.19 (0.74-1.89), no prior PARP inhibitor 0.81 (0.65-1.01), prior PARP inhibitor 0.95 (0.58-1.54). Median follow-up 22.6 mo (95% CI 19.5-28.1).

Nøttrup TJ, Lindemann K, Heitz F, et al. Presented at ESMO Congress 2026, abstract LBA39, 23 October. Not yet published.

Discussion & critique

Adding UV1 to olaparib with durvalumab did not significantly improve progression-free survival over olaparib alone at the 2-sided 0.05 level, so this randomised phase 2 trial missed its primary endpoint. The favourable restricted mean survival time difference was post hoc, and the signals in HRD-negative and PARP inhibitor-naive patients come from unplanned-for-confirmation subgroups, some very small, so they generate hypotheses only. The trial was open label with a progression-based endpoint, and the abstract reports no overall survival, response or safety data, so the cost of the triplet in toxicity cannot be judged. The study was funded by AstraZeneca and Ultimovacs.