Afami-cel — the first engineered cell therapy for a solid tumor — is indicated specifically for adults with unresectable or metastatic synovial sarcoma who have received prior chemotherapy, are positive for several human leukocyte antigens (HLAs), and whose tumors express melanoma-associated antigen A4, as determined by FDA-authorized companion diagnostic devices.
The single-dose treatment targets solid tumors expressing melanoma-associated antigen A4, a protein highly expressed in synovial sarcoma.
Synovial sarcoma is a rare form of cancer, which affects about 1000 people in the US each year. Malignant cells develop and form a tumor in soft tissues, often in the extremities.
“Adults with metastatic synovial sarcoma, a life-threatening form of cancer, often face limited treatment options in addition to the risk of cancer spread or recurrence,” Nicole Verdun, MD, director of the Office of Therapeutic Products in the FDA’s Center for Biologics Evaluation and Research, said in the agency press release announcing the approval. “Today’s approval represents a significant milestone in the development of an innovative, safe and effective therapy for patients with this rare but potentially fatal disease.”
T-cell receptor therapy, like chimeric antigen receptor (CAR) T-cell (CAR-T) therapy, involves altering patient T cells to fight cancer. While CAR-T therapy inserts an artificial receptor to target a specific surface protein on cancer cells, the T-cell receptor therapy modifies existing receptors to recognize an array of antigens on the surface of cancer cells — a promising strategy for targeting solid tumors.
The accelerated approval of afami-cel was based on the phase 2 SPEARHEAD-1 trial in 44 patients with synovial sarcoma who received a single infusion of the therapy. The trial had enrolled 52 patients, but 8 did not receive afami-cel, including 3 who died and 1 who withdrew.
According to the FDA announcement, the overall response rate was 43.2%, with a median time to response of 4.9 weeks. The median duration of response was 6 months (95% CI, 4.6 months to not reached). Among patients who responded, 39% had a duration of response of 12 months or longer.
“These results suggest that a one-time treatment with afami-cel has the potential to extend life while allowing responders to go off chemotherapy,” said lead investigator Sandra D’Angelo, MD, a sarcoma specialist at Memorial Sloan Kettering Cancer Center in New York City, in a company press release.
The prescribing information includes a boxed warning for serious or fatal cytokine release syndrome.
The most common nonlaboratory adverse reactions, occurring in at least 20% of patients, included cytokine release syndrome, nausea, vomiting, fatigue, infections, pyrexia, constipation, dyspnea, tachycardia, hypotension, diarrhea, and edema. The most common grade 3 or 4 laboratory abnormalities, occurring in at least 20% of patients, included decreased lymphocyte count, neutrophil count, white cell blood count, red blood cell, and platelet count.
The recommended dose is between 2.68x109 to 10x109 MAGE-A4 T-cell receptor–positive T-cells. The FDA notice specifies not using a leukodepleting filter or prophylactic systemic corticosteroids.
The list price for the one-time therapy is $727,000, according to Fierce Pharma.
A version of this article first appeared on Medscape.com.