Basak, Priyanka

8617 Background: Dato-DXd is an antibody-drug conjugate (ADC) composed of an anti-TROP2 monoclonal antibody linked to a potent topoisomerase I inhibitor payload. We report updated findings from TROPION-Lung02 (NCT04526691) evaluating Dato-DXd plus pembro with or without Pt-CT as 1L therapy for aNSCLC. Methods: Patients (Pts) received Dato-DXd (4 or 6 mg/kg) plus pembro 200 mg alone (doublet) or with Pt-CT (triplet; cisplatin 75 mg/m2 or carboplatin AUC 5) Q3W across 6 cohorts. Pts in the expansion stage were primarily treatment (tx)-naïve. PD-L1 expression was evaluated by tumor proportion score (TPS < 50% or ≥50%) using immunohistochemistry (22C3 assay). The primary objectives were safety and tolerability, with efficacy a secondary objective. Results: 96 pts were treated with doublet (n = 42) or triplet (n = 54) therapy in the 1L setting. At data cutoff (Oct 31, 2023), 45% and 20% of pts receiving doublet or triplet tx were ongoing. Median age was 66 years in both subgroups. Median treatment durations were 6.6 and 5.8 months. Across doublet and triplet tx, the most common any-grade (Gr) treatment-emergent adverse events (TEAEs) were stomatitis (57%, 33%) and nausea (40%, 46%), mainly Gr 1–2. Gr ≥3 TEAEs were seen in 57% and 76% of pts; serious TEAEs in 38% and 44%. TEAEs associated with Dato-DXd discontinuation occurred in 29% and 39% of pts receiving doublet or triplet tx. TEAEs associated with death were seen in 2% and 9%, none considered related to study drug. Efficacy outcomes, including ORR and preliminary PFS, in the 1L setting overall and by PD-L1 status are summarized in the Table. Conclusions: As 1L therapy for aNSCLC, Dato-DXd plus pembro with or without Pt-CT continues to demonstrate durable antitumor activity. Efficacy was observed regardless of PD-L1 expression. Tolerability of the combinations was as expected based on known profiles of the individual agents, with no new safety signals observed. To date, this is the largest dataset reported for any ADC combined with an anti-PD-1/L1 agent in the 1L setting for aNSCLC. Clinical trial information: NCT04526691 . [Table: see text]

9004 Background: Despite advances in first-line (1L) immunotherapy ± CT, most patients (pts) with aNSCLC experience disease progression, necessitating novel strategies. Dato-DXd is an antibody drug conjugate (ADC) composed of a humanized anti-TROP2 IgG1 monoclonal antibody covalently linked to a topoisomerase I inhibitor payload via a plasma-stable tetrapeptide-based cleavable linker. Dato-DXd had encouraging efficacy and manageable safety in heavily pretreated aNSCLC. Dato-DXd + immunotherapy yielded greater preclinical activity than either agent alone. Methods: TROPION-Lung02 (NCT04526691) is a phase 1b, global, dose-escalation and -expansion study evaluating Dato-DXd (4 or 6 mg/kg) + pembro 200 mg ± Pt-CT (cisplatin 75 mg/m2 or carboplatin AUC 5) every 21 days across 6 cohorts. Pts in escalation may have received ≤2 prior lines of therapy for aNSCLC. Pts in expansion were primarily treatment (tx) naive (pts receiving Dato-DXd + pembro may have ≤1 prior Pt-based tx). The primary objective is to assess safety and tolerability, including dose-limiting toxicities (DLTs). Secondary objectives include evaluation of efficacy, pharmacokinetics, and immunogenicity. Results: As of the Oct 31, 2022, data cutoff (DCO), 120 pts were treated. All cohorts met DLT criteria to move to escalation. Median age was 65 years. PD-L1 expression was <1%, 1%-49%, and ≥50% in 40%, 33%, and 26% of pts, respectively. Median tx duration was 4.6 mo, with 55% receiving tx at DCO. The most frequent any-grade (gr) tx-emergent adverse events (TEAEs) were nausea (45%) and stomatitis (45%). Gr ≥3 TEAEs occurred in 61% of pts; most frequent were neutrophil count decreased (8%) and amylase increased (8%). TEAEs that were serious, associated with discontinuation, or associated with death occurred in 31%, 24% (16% associated with Dato-DXd), and 6% of pts, respectively. Dose reductions due to TEAEs associated with Dato-DXd occurred in 17%. Drug-related interstitial lung disease occurred in 12 pts (10%; 9 gr 1/2; 3 gr 3). The objective response rate (ORR) with 1L Dato-DXd + pembro doublet and Dato-DXd + pembro + Pt-CT triplet tx was 60% (95% CI, 36%-81%; 12 [2 unconfirmed]/20) and 55% (95% CI, 39%-70%; 23 [5 unconfirmed]/42), respectively. The ORR for any line of therapy was 38% (95% CI, 25%-54%; 18 [2 unconfirmed]/47) with doublet and 47% (95% CI, 34%-60%; 28 [5 unconfirmed]/60) with triplet tx. In both subsets, the disease control rate was 85% and median duration of response was not reached. Responses were observed in all 3 PD-L1 expression level subgroups. Although immature, median progression-free survival (95% CI) was 10.8 (8.3-15.2) and 7.8 mo (5.5-NE) with doublet and triplet tx, respectively. Conclusions: Dato-DXd + pembro ± Pt-CT demonstrated tolerable safety with notable 1L activity in this first and largest dataset with an ADC + immunotherapy ± Pt-CT in aNSCLC pts. Clinical trial information: NCT04526691 .