Study in Metastatic Breast Cancer Patients Receiving Eftilagimod Alpha or Placebo in Combination With Paclitaxel Chemotherapy

Overview

The goal of this clinical trial is to compare the safety and efficacy of eftilagimod alpha (efti) in combination with paclitaxel standard of care chemotherapy in participants with metastatic breast cancer. The main questions it aims to answer are: * What is the optimal biological dose (OBD) of efti in combination with weekly paclitaxel chemotherapy? * Can efti combined with weekly paclitaxel chemotherapy prolong overall survival in participants with metastatic breast cancer if compared to weekly paclitaxel chemotherapy alone? In the first component of the trial (phase 2, lead-in) researchers will compare two groups (different dose levels of efti in combination with standard chemotherapy) to see if the treatment is safe and well tolerated and evaluate which is the optimal biological dose. In the second component of the trial (phase 3) researchers will assess if the treatment of metastatic breast cancer with the optimal biological dose of efti in combination with paclitaxel is superior compared to chemotherapy alone (placebo-controlled). The treatment concept of each trial component consists of a chemo-immunotherapy phase followed by an immunotherapy phase. In the first phase participants will be treated with efti plus paclitaxel chemotherapy or placebo plus paclitaxel chemotherapy. After completion of the chemotherapy per standard of care, participants will be treated with the study agent alone.

The AIPAC-003 trial consists of an open-label dose optimization lead-in component followed by a double-blinded, randomized, placebo-controlled phase 3 component. The main objectives of the dose optimization lead-in (phase 2) are to evaluate and compare the safety and tolerability of 2 different dose levels of efti (30 mg and 90 mg) combined with paclitaxel, and to define the optimal biological dose (OBD) of efti in combination with weekly paclitaxel for the phase 3 part of the trial. Recruitment to the dose-optimization lead-in will be considered complete when 29 participants per cohort are randomized and considered evaluable for OBD analysis. The main objective of the phase 3 is to demonstrate that overall survival (OS) is superior in participants treated with efti combined with weekly paclitaxel compared to weekly paclitaxel plus placebo. Approximately 771 participants will be randomized 2:1 to Arm A (active arm): paclitaxel + efti at OBD and Arm B (control arm): paclitaxel + placebo. The exact patient population will be defined after determination of the OBD. The duration of the trial will be approximately 24 months for the dose optimization lead-in component and 60 months for the phase 3 component. The phase 3 will start prior to the completion of the phase 2 (once the OBD has been defined). It is planned to conduct the trial at up to 20 sites in up to 4 countries across North America and Europe for the lead-in and at up to 150 sites in up to 25 countries across North America, Europe, Latin America and the Asian Pacific region for the phase 3.