Neoadjuvant Aitua (PD-1/CTLA-4 Bispecific) Plus Nab-Paclitaxel and Carboplatin for Advanced High-Grade Serous Ovarian Cancer

February 21, 2026 updated by: NING LI-GYN, Cancer Institute and Hospital, Chinese Academy of Medical Sciences

A Prospective, Randomized, Controlled Phase II Clinical Study of Albumin-Bound Paclitaxel/Carboplatin Combined With Aitua Combination Antibody (PD-1/CTLA-4 Bispecific Antibody) for the Neoadjuvant Treatment of Advanced High-Grade Serous Ovarian Cancer With Unsatisfactory Debulking

This is a prospective, randomized, controlled Phase II clinical study designed to evaluate the efficacy and safety of adding Aitua Combination Antibody (a PD-1/CTLA-4 bispecific antibody) to standard neoadjuvant chemotherapy for patients with advanced high-grade serous ovarian cancer.

The study focuses on patients who are newly diagnosed with Stage IIIC-IV ovarian, fallopian tube, or primary peritoneal cancer and are assessed as unable to achieve satisfactory tumor debulking (R0 resection) initially.

Participants will be randomized in a 1:1 ratio into two groups:

Experimental Group: Receives Nab-paclitaxel and Carboplatin combined with Aitua Combination Antibody.

Control Group: Receives Nab-paclitaxel and Carboplatin alone.

Both groups will receive 3 cycles of neoadjuvant treatment followed by Interval Debulking Surgery (IDS). The primary goal is to compare the R0 resection rate (complete removal of macroscopic tumor) between the two groups during surgery. Secondary goals include assessing pathological complete response (pCR), objective response rate, progression-free survival, and safety. The study also aims to explore how this combination therapy affects the tumor immune microenvironment.

Study Overview

Status

Not yet recruiting

Conditions

Intervention / Treatment

Detailed Description

Background and Rationale: Ovarian cancer has the highest mortality rate among gynecological malignancies, with High-Grade Serous Carcinoma (HGSC) being the most common subtype. HGSC is characterized by a highly immunosuppressive Tumor Immune Microenvironment (TiME), often referred to as an "immune desert," which limits the efficacy of single-agent immune checkpoint inhibitors (ICIs) targeting the PD-1/PD-L1 pathway.

Investigational Agent: Aitua Combination Antibody (QL1706) is a novel bifunctional antibody targeting both PD-1 and CTLA-4. Dual blockade of these pathways may synergistically activate anti-tumor immune responses: CTLA-4 inhibition promotes early T-cell activation in lymph nodes, while PD-1 inhibition reverses T-cell exhaustion within the tumor microenvironment. Previous studies in cervical cancer have shown that this bispecific antibody may offer improved efficacy with a manageable toxicity profile compared to combining two separate antibodies.

Chemotherapy Synergy: Albumin-bound paclitaxel (Nab-paclitaxel), a standard component of ovarian cancer treatment, avoids the need for corticosteroid pretreatment and has been shown to potentially enhance immune cell infiltration and regulate macrophage polarization. This study hypothesizes that combining Nab-paclitaxel/Carboplatin with the PD-1/CTLA-4 bispecific antibody will remodel the immune microenvironment and improve surgical outcomes.

Study Design: This is a single-center, open-label (with blinded assessment), randomized Phase II trial. Approximately 82 eligible patients will be stratified by FIGO stage (IIIC vs. IV) and randomized 1:1 to the experimental or control arm.

Neoadjuvant Phase: Patients receive 3 cycles of therapy (Q3W).

Surgical Phase: Patients with responsive or stable disease will undergo Interval Debulking Surgery (IDS). The primary endpoint is the R0 resection rate (no macroscopic residual disease).

Adjuvant Phase: Post-surgery, patients will continue treatment with the assigned regimen for additional cycles.

Translational Research: Tumor tissue, ascites, and peripheral blood will be collected at baseline, pre-surgery, and during therapy to analyze changes in immune cell subsets (e.g., via scRNA-seq, mIHC/mIF) and identify potential predictive biomarkers.

Study Type

Interventional

Enrollment (Estimated)

82

Phase

  • Phase 2

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • Age ≥ 18 years.
  • Histologically confirmed high-grade serous ovarian cancer (HGSC), fallopian tube cancer, or primary peritoneal cancer.
  • International Federation of Gynecology and Obstetrics (FIGO) stage IIIC-IV.
  • Eastern Cooperative Oncology Group (ECOG) performance status of 0-1.
  • Assessed by a multidisciplinary team (MDT) based on imaging (± laparoscopic exploration) as initially unable to achieve satisfactory tumor debulking (R0 resection).
  • At least one measurable lesion according to Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1 criteria.
  • Major organ function is basically normal.
  • Willing to provide tumor tissue, peripheral blood, and ascites samples for translational research.

Exclusion Criteria:

  • Pathological types other than high-grade serous carcinoma (HGSC).
  • Prior receipt of any form of anti-tumor therapy.
  • History of autoimmune disease or requiring immunosuppressive therapy.
  • Known allergy to study drug components.
  • Pregnant or lactating women.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Single

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: Nab-Paclitaxel + Carboplatin + Aitua Combo Ab
Participants receive Nab-paclitaxel (260 mg/m^2), Carboplatin (AUC 4-5), and Aitua Combination Antibody (5 mg/kg) intravenously on Day 1 of each 3-week cycle for 3 cycles as neoadjuvant therapy, followed by Interval Debulking Surgery (IDS).
Drug: Aitua Combination Antibody
Administered via intravenous infusion at a dose of 5 mg/kg on Day 1 of each 3-week cycle.
Other Names:
  • PD-1/CTLA-4 Bispecific Antibody
  • QL1706
Drug: Albumin-Bound Paclitaxel /nab-Paclitaxel
Administered via intravenous infusion at a dose of 260 mg/m^2 on Day 1 of each 3-week cycle.
Drug: Carboplatin (AUC 5)
Administered via intravenous infusion at a dose of AUC 5 on Day 1 of each 3-week cycle.
Procedure: Interval Debulking Surgery
Performed after 3 cycles of neoadjuvant therapy. The goal is to achieve R0 resection (no macroscopic residual disease).
Active Comparator: Nab-Paclitaxel + Carboplatin
Participants receive Nab-paclitaxel (260 mg/m^2) and Carboplatin (AUC 4-5) intravenously on Day 1 of each 3-week cycle for 3 cycles as neoadjuvant therapy, followed by Interval Debulking Surgery (IDS).
Drug: Albumin-Bound Paclitaxel /nab-Paclitaxel
Administered via intravenous infusion at a dose of 260 mg/m^2 on Day 1 of each 3-week cycle.
Drug: Carboplatin (AUC 5)
Administered via intravenous infusion at a dose of AUC 5 on Day 1 of each 3-week cycle.
Procedure: Interval Debulking Surgery
Performed after 3 cycles of neoadjuvant therapy. The goal is to achieve R0 resection (no macroscopic residual disease).

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Rate of R0 resection
Time Frame: At the time of surgery, up to 12 weeks
Defined as the percentage of participants achieving optimal debulking surgery with no macroscopic residual disease (R0) after neoadjuvant therapy. This is assessed by the surgeon at the time of interval debulking surgery (IDS).
At the time of surgery, up to 12 weeks

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Pathological complete response (pCR) rate
Time Frame: At the time of surgery, up to 12 weeks
Defined as the proportion of participants with no evidence of invasive cancer in the surgical specimens collected during interval debulking surgery (IDS).
At the time of surgery, up to 12 weeks
Objective response rate (ORR)
Time Frame: From baseline up to approximately 2 years
Defined as the percentage of participants who achieve a best overall response (BOR) of complete response (CR) or partial response (PR) according to Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1, based on independent radiological review.
From baseline up to approximately 2 years
Disease control rate (DCR)
Time Frame: From baseline up to approximately 2 years
Defined as the percentage of participants who achieve a best overall response (BOR) of complete response (CR), partial response (PR), or stable disease (SD) according to Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1.
From baseline up to approximately 2 years
Progression-free survival (PFS)
Time Frame: From randomization up to approximately 2 years
Defined as the time from randomization to the first documented disease progression per Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1, or death from any cause, whichever occurs first.
From randomization up to approximately 2 years
Incidence and severity of adverse events (AEs)
Time Frame: Through 28 days after the last dose of study drug, up to approximately 2 years
Safety will be assessed by monitoring the frequency and severity of adverse events (AEs) and serious adverse events (SAEs), graded according to National Cancer Institute Common Terminology Criteria for Adverse Events (NCI CTCAE) version 5.0. This includes monitoring for immune-related adverse events (irAEs).
Through 28 days after the last dose of study drug, up to approximately 2 years

Other Outcome Measures

Outcome Measure
Measure Description
Time Frame
Change in tumor immune microenvironment (TiME) characteristics
Time Frame: At baseline, and at the time of surgery (up to 12 weeks)
Exploratory analysis of immune cell subsets, such as cluster of differentiation 8 positive (CD8+) T cells, regulatory T cells (Tregs), myeloid-derived suppressor cells (MDSCs), and tumor-associated macrophages (TAMs), in tumor tissue and peripheral blood. This uses single-cell RNA sequencing (scRNA-seq), multiplex immunohistochemistry/immunofluorescence (mIHC/mIF), and flow cytometry to evaluate the immunomodulatory effects of the treatment.
At baseline, and at the time of surgery (up to 12 weeks)

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Cancer Institute and Hospital, Chinese Academy of Medical Sciences

Collaborators

Qilu Pharmaceutical Co., Ltd.

Investigators

  • Principal Investigator: Ning Li, MD, Cancer Institute and Hospital, Chinese Academy of Medical Sciences

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Estimated)

March 1, 2026

Primary Completion (Estimated)

May 30, 2027

Study Completion (Estimated)

June 30, 2027

Study Registration Dates

First Submitted

February 12, 2026

First Submitted That Met QC Criteria

February 21, 2026

First Posted (Actual)

February 25, 2026

Study Record Updates

Last Update Posted (Actual)

February 25, 2026

Last Update Submitted That Met QC Criteria

February 21, 2026

Last Verified

February 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • 2025-I2M-C&T-B-065

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

IPD Plan Description

Due to institutional privacy regulations and patient confidentiality, individual participant data (IPD) will not be shared publicly.

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Clinical Trials on Primary Peritoneal Cancer

Clinical Trials on Aitua Combination Antibody

Search Similar Trials

Sponsors and Collaborators

Medical Conditions

Drug Interventions

CROs by country

CROs in Singapore

Conditions

Rare Diseases

Drug Interventions

Dietary Supplements

Sponsor/Collaborators

Locations

Subscribe