Abstract 1140P
Background
Immunochemotherapy is the standard first-line treatment for NSCLC. However, there is no consensus on the optimal combination strategy and the maintenance regimen. We developed a regimen that aims to minimize the use of chemo without compromising efficacy and compared its effects to different first-line treatments.
Methods
We retrospectively evaluated 1,510 EGFR/ALK wild-type NSCLC patients who received immunochemotherapy in our center from 2019 to 2021. Patients who had controlled disease after 2-6 cycles of first-line immunotherapy (I) plus chemo (C) with or without anti-angiogenesis (A) were included. There are 4 common regimens: 4-6 cycles of initial induction followed by I+C+A maintenance (group 1, I+C+A), I+C maintenance (group 2, I+C), or I maintenance alone (group 3, I); chemo-holiday regimen: 2-4 cycles of immunochemotherapy plus anti-angiogenesis followed by I+A maintenance (group 4, I+A). For group 3-4, rechallenge with initial chemo-agents will be given upon the first progression, those achieving controlled disease can be repeatedly followed by another chemo-free period. The primary outcome was PFS. Notably, for group 3-4, PFS was defined as the time between treatment initiation and failure of rechallenge (last PD).
Results
A total of 140 eligible patients who entered the maintained phase were analyzed. There were 20, 40, 42 and 38 patients in group 1 to 4, with comparable baselines. The median PFS were similar between group 1 (22.6 months), 2 (21.0 months) and 4 (21.5 months), whereas PFS was relatively inferior in group 3 with immune alone (13.4 months). Median chemo-free duration in group 3 and 4 were 6.3 and 14.2 months. During the maintenance period of group 1 to 4, 25%, 25%, 19%, 42% of patients experienced PR again and 55%, 65%, 48% and 61% of patients maintained durable disease control beyond 6 months. In group 4, 50% of patients achieved PR and returned to chemo-free maintenance upon the first PD.
Conclusions
We designed a chemo-holiday regimen featured by short-term enhanced induction of antiangiogenic immunochemotherapy, maintenance by I+A, with on-demand chemo-rechallenge, and demonstrated its equivalence in PFS with less toxicity and cost. Additionally, anti-angiogenesis is crucial during chemo-free maintenance, compared to its role in chemo-on maintenance.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.