1368P - Correlation between depth of response at 6 months and survival in patients (pts) with metastatic non-small cell lung carcinoma (mNSCLC): SPORE trial

Background

Immunotherapy (ICI)-based treatments are the standard of care in the management of mNSCLC without oncogenic addiction. Recent data showed moderate correlations of overall response rate (ORR) with overall survival (OS) for first-line ICI-based regimens. We hypothesize that depth tumor response at 6 months beyond the response evaluation criteria in solid tumors (RECIST)-defined by a 30% threshold for OR will provide prognostic relevance in mNSCLC.

Methods

We included all consecutive mNSCLC pts without sensitizing EGFR or ALK mutations treated in first-line setting with a combination with ICI and chemotherapy still alive and on first-line therapy at 6 months at 5 french centers. Tumor shrinkage was categorized according to the best percentage change in the sum of the largest diameter of target lesions, with the following tumor response categories: −100% to −60%, −60% to −30%, −30% to 0%, 0% to +20%, ≥+20%. Outcome was computed using Kaplan-Meier curves and correlation with OS was assessed via Cox regression, including a 6 months landmark.

Results

We enrolled 178 pts with mNSCLC between 02/2019 and 12/2021; median age was 61 years old; 65% male; ECOG was 0-1 for 177 pts (99%); 163 (92%) current or former smoker; 149 pts (84%) had adenocarcinoma and 23 pts (13%) had squamous cell carcinoma; PD-L1 status : 47 pts (26%) had > 50%, 55 pts (31%) between 1-49%, 76 pts (43%) had < 1%; 27% had brain metastasis at diagnosis; baseline imagery was CT-scan for 86 pts (48%) and PET-scans for 92 pts (52%); tumor response categories: 38 pts(22%) −100% to −60%, 55 pts (31%)−60% to −30%, 52 pts (30%) −30% to 0%, 8 pts (4%) 0% to +20%, 22 pts (13%) ≥+20%. Median OS in overall population was 35.1 months (CI, 95% 31.1-NA). At 6 months, major tumor shrinkage of −100% to −60% occurred in approximately 22% of patients and the median OS was not reached in this group. Median OS expectations steadily decreased with depth of remission according to tumor response categories (45.6, 31.8, 19.9, and 16.1 months respectively, p < 0,0001).

Conclusions

This is the first and largest analysis of best tumor response in mNSCLC. In this cohort, the depth of response at 6 months seems to correlate with patients' overall survival.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

The authors.

Funding

Has not received any funding.

Disclosure

F. Moinard-Butot: Financial Interests, Personal, Advisory Board: Bristol Myers Squibb; Other, Hospitality: Merck, Gilead. G. Justeau: Non-Financial Interests, Advisory Role: BMS. O. Bylicki: Financial Interests, Personal, Advisory Board, Expert Board: BMS, Roche, Takeda; Financial Interests, Personal, Other, Travel congress: MSD; Financial Interests, Personal, Advisory Board, expert board: AstraZeneca, Janssen; Financial Interests, Personal, Advisory Board, Board: MSD; Financial Interests, Personal, Other, Travel Congress: AstraZeneca. All other authors have declared no conflicts of interest.