SPEARHEAD-1: afami-cel, the first engineered T-cell receptor therapy approved for a solid tumour, in synovial sarcoma
T cells engineered with a receptor recognising the MAGE-A4 cancer antigen shrank tumours in 37% of patients with advanced synovial sarcoma or myxoid liposarcoma, leading to the first approval of a TCR-T therapy.
SPEARHEAD-1 was a single-arm phase 2 trial of afamitresgene autoleucel (afami-cel), autologous T cells transduced with an affinity-enhanced T-cell receptor recognising a MAGE-A4 peptide presented by HLA-A*02, in 52 patients with advanced synovial sarcoma (44) or myxoid round cell liposarcoma (8) after prior anthracycline or ifosfamide. Patients were screened for HLA-A*02 and MAGE-A4 expression, received cyclophosphamide-fludarabine lymphodepletion and a single infusion. The overall response rate was 37% (39% in synovial sarcoma) with a median duration of response of about 12 months. Cytokine release syndrome occurred in 71% (grade 3 in a small minority) and prolonged cytopenias were common. The FDA granted accelerated approval in August 2024, the first TCR-T therapy and the first engineered T-cell therapy for a solid tumour.
- 52 patients (44 synovial sarcoma, 8 myxoid round cell liposarcoma); HLA-A*02-positive and MAGE-A4-positive.
- Overall response 37% overall; 39% in synovial sarcoma; 25% in MRCLS.
- Median duration of response about 12 months; some responses lasting beyond 2 years.
- CRS 71%, mostly grade 1-2; prolonged grade 3-4 cytopenias frequent.
- Roughly a third of screened patients were eligible after HLA and antigen testing.
Afami-cel showed that T cells can be redirected against an intracellular cancer antigen, something CAR-T cannot do, and produced meaningful responses in a rare sarcoma with few options. It opens a path to TCR-T against other shared antigens and neoantigens. Restriction to one HLA type and one antigen, plus complex manufacturing, means it will help a small, defined group.
- Single-arm; approval based on response rate.
- Eligibility limited to HLA-A*02 carriers with MAGE-A4 expression, excluding most patients.
- Durability is modest and antigen loss or HLA loss can drive relapse.
- Affinity-enhanced TCRs carry theoretical off-target cross-reactivity risk, as seen fatally with an earlier MAGE-A3 TCR.