Neoadjuvant Pamiparib/Chemo Combo Leads to R0 Resections in Advanced Ovarian Cancer

Neoadjuvant treatment pamiparib (BGB-290; Partruvix in China) in combination with paclitaxel, carboplatin, and bevacizumab led to R0 resections with a manageable safety profile in patients with newly diagnosed advanced ovarian cancer, according to preliminary data from a single‑arm, prospective phase 2 trial (ChiCTR2200059119) presented at the 2025 ASCO Annual Meeting.¹

Among the 29 enrolled patients, 2 withdrew consent after receiving 1 cycle of neoadjuvant therapy. Of the remaining 27 patients, 17 received 4 cycles, 7 received 3 cycles, and 3 received 2 cycles. Interval debulking surgery was performed in 24 patients, all of whom achieved R0 resection. Two patients declined surgery, and 1 patient received modified treatment due to elevated CA125 levels.

Although no patients who underwent surgery achieved a pathologic complete response (pCR), a chemotherapy response score (CRS) of 3 was reported in 34.8% of patients who underwent surgery. A CRS of 2 occurred in 65.2% of patients, and 4.3% had a CRS of 1. A higher CRS is associated with improvements in progression-free survival (PFS) and overall survival.²

Common adverse effects (AEs) of any grade included leukopenia (96.6%), neutropenia (96.6%), anemia (96.6%), and thrombocytopenia (72.4%).¹ These AEs occurred at grade 3/4 in 58.6%, 72.4%, 27.6%, and 24.1% of patients, respectively. No unexpected toxicities were reported, and the regimen was generally tolerated within the expected safety profile for the included agents.

“The addition of pamiparib to neoadjuvant chemotherapy plus bevacizumab offers promising efficacy and acceptable safety in newly diagnosed advanced ovarian cancer,” lead study author Jing Liu, MD, of the Department of Gynecology at Fujian Medical University Cancer Hospital in China, and colleagues wrote in a poster presentation of the data.

In May 2021, China’s National Medical Products Administration approved pamiparib for the treatment of patients with germline BRCA mutation–associated recurrent advanced ovarian, fallopian tube, or primary peritoneal cancer who have been treated with 2 or more lines of chemotherapy.³

Phase 2 Study Design and Baseline Patient Characteristics

The phase 2 trial was a single‑arm, prospective study designed to evaluate the safety and efficacy of incorporating pamiparib into a neoadjuvant regimen for patients with newly diagnosed advanced ovarian cancer.¹ Eligible patients were 18 years of age or older with histologically confirmed FIGO stage III to IV high‑grade serous or endometrioid adenocarcinoma at FIGO stage III to IV. An ECOG performance status of 0 to 2 was also required. All patients needed to be considered ineligible for optimal primary debulking surgery and were required to have measurable disease per RECIST 1.1 criteria.

Patients received neoadjuvant chemotherapy consisting of paclitaxel at 175 mg/m² on day 1 plus carboplatin at an area under the curve of 5 on day 2 every 3 weeks for up to 6 cycles; bevacizumab at 15 mg/kg on day 1 every 3 weeks before being discontinued 6 weeks before surgery; and pamiparib at 40 mg twice daily for up to 6 cycles.

The primary end point was the proportion of patients achieving a CRS of 3 at interval debulking surgery. Key secondary end points included the pCR rate, R0 resection rate, PFS, and safety.

Baseline characteristics were reported for 29 enrolled patients. The median age was 61 years (range, 44‑79). Most patients had FIGO stage III disease at diagnosis (65.5%), followed by stage IVB (31.0%) and stage IVA (3.4%). The majority of tumors were high‑grade serous adenocarcinoma (96.7%), with 1 patient (3.4%) having endometrioid adenocarcinoma.

References

1. Liu J, Chang L, Zhang X, et al. Neoadjuvant pamiparib in patients with newly diagnosed advanced ovarian cancer: a single-arm, prospective phase 2 trial. J Clin Oncol. 2025;43(suppl 16):5593. doi:10.1200/JCO.2025.43.16_suppl.5593
2. Zannoni GF, Angelico G, Spadola S, et al. Chemotherapy response score (CRS): A comprehensive review of its prognostic and predictive value in high-grade serous carcinoma (HGSC). Gynecol Oncol. 2025;194:1-10. doi:10.1016/j.ygyno.2025.01.012
3. China NMPA approves PARP inhibitor pamiparib for patients with previously treated advanced ovarian cancer. News release. BeOne Medicines. May 7, 2021. Accessed August 6, 2025. https://hkexir.beonemedicines.com/news/china-nmpa-approves-parp-inhibitor-pamiparib-for-patients-with-previously-treated-advanced-ovarian-cancer/305b6eb6-ecb3-426a-b382-4bda796d8c1f