Abstract No : Abstract #1422MO
Indication : Gastric Cancer
Intervention : Trastuzumab deruxtecan
Company : Astrazeneca/Daiichi Sankyo
Technology : anti-HER2 ADC
Results:
20 (cohort 1) and 24 (cohort 2) pts were treated with T-DXd 6.4 mg/kg q3w. Most were from Japan (cohort 1, 80.0%; cohort 2, 79.2%) and had received a median of 2 prior lines of therapy. At data cutoff (8 Nov 2019), no pts in cohort 1 and 2 in cohort 2 (8.3%) remained on treatment (median duration, 4.2 and 2.8 mo). In cohort 1, confirmed ORR was 26.3% (5/19, all PR); 12 pts had stable disease (DCR, 89.5%). Median PFS was 4.4 mo (95% CI, 2.7-7.1 mo); median OS was 7.8 mo (95% CI, 4.7 mo-NE), with a 12-mo OS rate of 40.0%. Confirmed ORR in cohort 2 was 9.5% (2/21, all PR); confirmed DCR was 71.4%. Median PFS and OS were 2.8 mo (95% CI, 1.5-4.3 mo) and 8.5 mo (95% CI, 4.3-10.9 mo), with a 12-mo OS rate of 25.7%. Grade ≥ 3 adverse events occurred in 70.0% and 79.2% of pts in cohorts 1 and 2. Decreased appetite (65.0%; 75.0%), nausea (55.0%; 79.2%), and neutrophil count decreased (45.0%; 50.0%) were most common. One pt in each cohort (grade 1 = 1; grade 2 = 1) had T-DXd–related interstitial lung disease.
Conclusion:
T-DXd showed preliminary evidence of clinical activity in pts with previously treated, HER2-low gastric or GEJ cancer. The safety profile was similar to that in the HER2+ primary cohort.
