ESMO Immuno-Oncology Congress 2024

Abstract 136P

Background

We conducted a multicenter, open-label, phase 2 study to evaluate TIS + platinum-based chemo (cohort 1) or TIS + mono-chemo + beva (cohort 2) in EGFR-mutated nsq-NSCLC pts who progressed on EGFR TKI therapies. Our previous results showed that both cohorts met the primary endpoint (1-year PFS rate). Here, we report the updated analysis with extended follow-up.

Methods

EGFR-mutated, nsq-NSCLC pts who had failed prior EGFR-TKIs received induction therapy with TIS + carboplatin (CBP) + nab-paclitaxel (nab-P; cohort 1) or TIS + nab-P + beva (cohort 2) every 3 weeks for 4 cycles, followed by maintenance therapy with TIS + pemetrexed (cohort 1) or TIS + beva (cohort 2) for up to 31 cycles.

Results

A total of 123 pts were enrolled (cohort 1, n=69; cohort 2, n=54). As of Aug 2, 2024, minimum study follow-up time (from the last patient’s first dose to data cutoff) was 32.3 and 17.1 mo, respectively for cohort 1 and cohort 2. Median OS was 27.1 mo in cohort 1, and 2-year and 3-year OS rates were 53.5% and 38.2%, respectively. For cohort 2, median OS was not reached, with 2-year OS rate of 61.4%. Pts with EGFR exon 21 L858R mutation had significantly longer OS than those with exon 19 deletion in cohort 1, while no similar trend was observed in cohort 2. Median PFS was 7.6 and 10.3 mo, respectively (Table). After prolonged follow-up, toxicity was manageable, with no new safety signals observed in both cohorts. Table: 136P

	Cohort 1 TIS + CBP + nab-P	Cohort 2 TIS + nab-P+ beva
Minimum study follow-up time∗, mo	32.3	17.1
Median OS, mo (95% CI)	27.1 (17.5, 36.9)	NR (19.2, NE)
OS rate, % (95% CI)
1-year	75.2 (62.2, 84.2)	78.8 (65.1, 87.7)
2-year	53.5 (40.1, 65.1)	61.4 (45.3, 74.1)
3-year	38.2 (24.9, 51.5)	NR (NE, NE)
Median PFS, mo (95% CI)	7.6 (5.8, 9.4)	10.3 (6.4, 14.5)
1-year PFS rate, % (90% CI)	25.4 (16.4, 35.3)	42.2 (30, 53.8)

^∗From the last patient’s first dose to data cutoff. NR, not reached; NE, not estimable.

Conclusions

TIS + platinum-based chemo (cohort 1) and TIS + mono-chemo + beva (cohort 2) demonstrated encouraging OS benefits and manageable toxicity for pts with EGFR-mutated nsq-NSCLC after EGFR TKI failure with extended follow-up. This study expands the treatment options for this patient population, allowing clinicians to tailor their choices based on individual patient circumstances.