This was an open-label, Phase II, randomized, multicenter study to assess the efficacy, safety, and pharmacokinetic characteristics of the following three combinations: LAG525 + spartalizumab (PDR001) (Arm 1), LAG525 + spartalizumab (PDR001) + carboplatin (Arm 2), and LAG525 + carboplatin (Arm 3) in participants with advanced triple-negative breast cancer (TNBC) which progressed after adjuvant or one prior line of systemic therapy for metastatic disease.~Participants were assigned to one of the three treatment arms in a ratio of 1:1:1. In protocol amendment 3 (released on 28-Mar-2019), enrollment to treatment Arm 1 (LAG525 + spartalizumab) was prematurely closed due to a higher discontinuation rate due to progressive disease and all subsequent enrolled patients were randomized to Arms 2 and 3 only, in a ratio of 1:1.~Study treatment continued until disease progression, unacceptable toxicity, pregnancy, investigator/participant decision, start of a new anti-neoplastic therapy, withdrawal of consent, lost to follow-up, death, or study was terminated by the sponsor. The investigator might decide to stop carboplatin after 6 cycles, even if the above criteria were not met. Participants who continued to derive clinical benefit from the treatment based on the investigator's evaluation following their completion of this trial might receive post-trial access (PTA) i.e. rollover protocol or a post-study drug supply (PSDS).~The end of study was defined as the earliest occurrence of one of the following: (1) all participants had died or (2) discontinued from the study, or (3) another clinical study became available that could continue to provide study treatment in this participant population and all ongoing participants were eligible to be transferred to that clinical study.
The main purpose of this study was to assess the antitumor activity of three combinations: i) LAG525 + spartalizumab; ii) LAG525 + spartalizumab + carboplatin, and iii) LAG525 + carboplatin in participants with advanced triple-negative breast cancer (TNBC) in first or second line therapy.