54O Health state impacts of afamitresgene autoleucel (afami-cel) in advanced synovial sarcoma and myxoid/round cell liposarcoma: SPEARHEAD-1 cohort 1

Afamitresgene autoleucel (afami-cel) is an autologous engineered T-cell receptor T-cell therapy targeting tumors expressing melanoma-associated antigen A4 (MAGE-A4). Cohort 1 of the phase 2 SPEARHEAD-1 trial showed a response rate of 38.6% and 25.0% and a median duration of response of 11.6 months and 4.2 months in advanced synovial sarcoma (SyS) and myxoid/round cell liposarcoma (MRCLS), respectively. We analyzed the effects of treatment on pts’ health state and quality of life. Afami-cel was infused into pts following lymphodepletion chemotherapy. ECOG performance status (PS) at baseline; Days 8, 15, 22, 29; Weeks 6, 8, 12, 16, 24; and Months 8, 10, 12, and 14, and EQ-5D-3L at baseline and Weeks 8, 16, and 24 post infusion were recorded. EQ-5D-3L visual analogue scores (VAS) and domain changes, Paretian Classification of Health Change (PCHC), and correlations with clinical response (assessed by RECIST v1.1 by investigators) were analyzed. Baseline PS was recorded for 52 pts (PS 0, n=27; PS 1, n=25). As of August 30, 2023, at Days 8 and 15 post infusion, 63% (30 of 48 recorded) and 75% (39 of 52 recorded) maintained or improved their PS, respectively, and 38% (18 of 48) and 25% (13 of 52) had a deterioration in PS from baseline. At Days 22 and 29, 78% (40 of 51 recorded) and 78% (38 of 49 recorded), respectively, maintained or improved their PS. From Week 6 to Month 14, 87–100% of pts with reported PS had an improved or maintained PS compared with baseline. Median VAS EQ-5D-3L health score at baseline was 61 in 45 pts, improving to 80 at Week 24 (n=19). Median time to next treatment or death was 10.0 months in the 27 pts with stable/improving VAS and 5.7 months in the 7 pts with worsening VAS. At baseline, of the 45 pts completing EQ-5D-3L domain analysis, 76% had pain/discomfort and 58% had anxiety/depression. 74% (25 of 34) of pts with baseline and ≥1 subsequent time point had a better/no change best PCHC assessment vs baseline. PCHC correlated with disease control. These pt-reported outcomes suggest that clinical responses to afami-cel in pts with advanced SyS/MRCLS were associated with maintenance or improvement in overall health and quality of life.