ROSELLA Trial Meets OS End Point and More Ovarian Cancer News

Recent clinical developments in the treatment of platinum-resistant ovarian cancer (PROC) have introduced several novel therapeutic classes, including selective glucocorticoid receptor antagonists, PARG inhibitors, antibody-drug conjugates (ADCs), and personalized immunotherapies.

For oncology nurses and advanced practice providers (APPs), these advancements represent a shifting paradigm toward biomarker-driven precision medicine and combinations designed to overcome traditional chemotherapy resistance while managing specific toxicity profiles.

Phase 3 ROSELLA Trial Reaches OS End Point in PROC

The pivotal phase 3 ROSELLA trial (NCT05257408) evaluating relacorilant in combination with nab-paclitaxel (Abraxane) has met its primary end point of overall survival (OS) in patients with PROC.¹ Patients treated with the combination experienced a 35% reduction in the risk of death vs those receiving nab-paclitaxel alone (HR, 0.65; P = .0004). The median OS for the relacorilant arm was 16.0 months, representing a 4.1-month improvement over the 11.9 months observed in the monotherapy arm.

“Relacorilant combined with nab-paclitaxel does not require biomarker selection, which means there is no special testing that needs to be done for a patient to be eligible for this combination when it becomes available,” explained researcher Alexander Olawaiye, MD, in an interview with Oncology Nursing News at the 2025 ASCO Annual Meeting. “Simply, the patients that are eligible are those who have been treated for ovarian cancer and who have platinum-resistant ovarian cancer.”

Relacorilant is an oral selective glucocorticoid receptor (GR) antagonist that modulates cortisol activity without binding to other hormone receptors. The adverse event (AE) profile for relacorilant was comparable between the combination and nab-paclitaxel monotherapy arms, and the efficacy findings were consistent across the study population without requiring specific biomarker selection. The FDA assigned a target action date of July 11, 2026, for the treatment after accepting a new drug application (NDA) for the treatment in September.

ROSELLA previously met its primary end point of progression-free survival (PFS), and updated results were presented at the 2025 ASCO Annual Meeting. Results from a poor-prognosis subgroup analysis presented at the 2025 ESMO Gynecologic Cancers Congress demonstrated that patients with a platinum-free interval of 1 to 6 months had improved PFS with the combination compared with nab-paclitaxel alone.²

PARG Inhibitor Receives Fast Track Designation in BRCA+ Platinum-Resistant HGSOC

The FDA has granted fast track designation to ETX-19477 for the treatment of adult patients with BRCA-mutated, platinum-resistant, high-grade serous ovarian cancer (HGSOC), according to a news release from 858 Therapeutics, the developer of the drug.³ ETX-19477 is an oral, selective inhibitor of poly-ADP-ribose glycohydrolase (PARG), an enzyme responsible for removing poly-ADP-ribose chains from proteins during the DNA damage response. This mechanism is distinct from PARP inhibition and is designed to lead to selective cell death in tumors with replication fork defects.

Initial clinical data from an ongoing phase 1/2 trial suggest anti-tumor activity at tolerable doses, per a statement from Jeffrey Stafford, PhD, the CEO of 858 Therapeutics, in the news release. The study is currently enrolling patients to further assess the safety, pharmacokinetics, and tolerability of the agent.

ADC Earns Breakthrough Therapy Status Across PROC Subgroups

Sofetabart mipitecan (LY4170156) has received breakthrough therapy designation for patients with platinum-resistant epithelial ovarian, fallopian tube, or primary peritoneal cancer who have previously received bevacizumab (Avastin) and, if eligible, mirvetuximab soravtansine (Elahere), according to a news release shared by Eli Lilly and Company.⁴ This agent is a novel folate receptor alpha (FRα)-directed ADC utilizing an exatecan payload and a proprietary linker.

Preliminary phase 1 ((NCT06400472) results demonstrated responses across all levels of FRα expression, including in patients who had progressed on prior mirvetuximab soravtansine. The tolerability profile is of particular interest to supportive care teams, as initial data show low rates of peripheral neuropathy, alopecia, and interstitial lung disease (ILD), and no significant ocular toxicity. The treatment is currently being investigated as monotherapy in patients with PROC and in combination with bevacizumab in patients with platinum-sensitive ovarian cancer (PSOC) the phase 3 FRAmework-01 trial (NCT07213804).

Updated Results Report 3-Year Response With Vaccine Immunotherapy Plus Pembrolizumab/Low-Dose Cyclophosphamide in EOC

Data from the phase 1b/2 PESCO trial (NCT03029403) highlight the potential for sustained responses using maveropepimut-S (MVP-S) combined with pembrolizumab (Keytruda) and intermittent low-dose cyclophosphamide in patients with recurrent epithelial ovarian cancer (EOC).⁵

The study reported that 1 subject has remained in complete response for 3 years following the first cycle of therapy. In patients with platinum-resistant disease, the overall response rate (ORR) was 16% and the disease control rate (DCR) was 54%, exceeding the 11.8% ORR typically seen with single-agent chemotherapy. The combination was reported to be well-tolerated.

MVP-S is a vaccine immunotherapy targeting survivin, a tumor-associated antigen highly expressed in ovarian cancer but nearly undetectable in normal tissue.

Cellular Immunotherapy Yields Survival Benefit vs Placebo in cTMB-H HRP Ovarian Cancer

The phase 2b VITAL trial (NCT02346747) of gemogenovatucel-T (Vigil), an autologous tumor-cell immunotherapy, demonstrated a significant OS benefit in patients with newly diagnosed stage IIIb to IV epithelial ovarian cancer.⁶ Patients with a clonal tumor mutational burden-high (cTMB-H) and homologous recombination proficient (HRP) profile achieved a median OS of 68 months with gemogenovatucel-T maintenance therapy compared with 19 months with placebo (HR, 0.23; P = .008). Patients receiving the experimental treatment had a 7-year OS rate of 45% vs 8% with placebo in the cTMB-H/HRP subset.

According to a news release from Gradalis, Inc., gemogenovatucel-T’s developer, the agent had a “very favorable safety profile” across the 91 patients enrolled, with no grade 3 or worse treatment-related AEs, a median follow-up of 8.4 years, no long-term issues such as myelodysplastic syndrome or acute myeloid leukemia, and no discontinuations attributed to toxicity.

The most frequent AEs were mild injection-site reactions. This favorable safety profile and the durable survival benefit in HRP tumors, a population that has historically not responded well to PARP or PD-1 inhibitors, have led to an FDA regenerative medicine advanced therapy (RMAT) fast track designation to support expedited development, according to a statement from John Nemunaitis, MD, the chief scientific officer and co-founder of Gradalis.

References

1. Overall survival primary endpoint met in Corcept’s pivotal phase 3 ROSELLA trial of relacorilant in patients with platinum-resistant ovarian cancer. News release. Corcept Therapeutics Incorporated. January 22, 2026. Accessed January 28, 2026. https://www.businesswire.com/news/home/20260122359919/en/Overall-Survival-Primary-Endpoint-Met-in-Corcepts-Pivotal-Phase-3-ROSELLA-Trial-of-Relacorilant-in-Patients-with-Platinum-Resistant-Ovarian-Cancer
2. Lorusso D, Gladieff L, Gilbert L, et al. Phase III results of relacorilant + nab-paclitaxel vs nab-paclitaxel in platinum-resistant ovarian cancer (PROC) (ROSELLA, GOG-3073, ENGOT-ov72): secondary endpoints. Presented at: 2025 ESMO Gynecological Cancer Congress; June 19-21, 2025; Vienna, Austria. Abstract 70O.
3. 858 Therapeutics announces FDA fast track designation for PARG inhibitor ETX-19477 for the treatment of patients with BRCA-mutated, platinum-resistant ovarian cancer. News release. 858 Therapeutics. January 8, 2026. Accessed January 28, 2026. https://www.businesswire.com/news/home/20260108319598/en/858-Therapeutics-Announces-FDA-Fast-Track-Designation-for-PARG-Inhibitor-ETX-19477-for-the-Treatment-of-Patients-with-BRCA-Mutated-Platinum-Resistant-Ovarian-Cancer
4. Lilly's sofetabart mipitecan receives U.S. FDA's Breakthrough Therapy designation for the treatment of certain patients with platinum-resistant ovarian cancer. News release. Eli Lilly and Company. January 20, 2026. Accessed January 28, 2026. https://investor.lilly.com/news-releases/news-release-details/lillys-sofetabart-mipitecan-receives-us-fdas-breakthrough
5. BioVaxys reports positive clinical study results from phase 1B/2 PESCO trial of MVP-S with pembrolizumab (Keytruda (TM)) and low-dose cyclophosphamide for patients with recurrent epithelial ovarian cancer (EOC). News release. BioVaxys Technology Corp. January 20, 2026. Accessed January 28, 2026. https://www.newsfilecorp.com/release/280882
6. Gradalis’ Vigil® demonstrates significant survival benefit in cTMB-H / HRP ovarian cancer patients; phase 2b VITAL trial analysis published in JCO – Precision Oncology. News release. Gradalis, Inc. January 14, 2026. Accessed January 28, 2026. https://www.globenewswire.com/news-release/2026/01/14/3219157/31499/en/Gradalis-Vigil-Demonstrates-Significant-Survival-Benefit-in-cTMB-H-HRP-Ovarian-Cancer-Patients-Phase-2b-VITAL-Trial-Analysis-Published-in-JCO-Precision-Oncology.html