Synovial sarcoma recurrent

To determine, for patients with advanced or recurrent synovial sarcoma not suitable for surgical resection and resistant to anthracycline, the safety and efficacy of the infusion of autologous T lymphocytes expressing NY-ESO-1 antigen-specific T-cell receptor gene and siRNAs to inhibit the expression of endogenous T-cell receptors (product code: TBI-1301).

Eligible Japanese patients (HLA-A*02:01 or *02:06, NY-ESO-1-positive tumor expression) received cyclophosphamide 750 mg/m2 on days -3 and -2 (induction period) followed by a single dose of 5 x 109 (±30%) TBI-1301 cells as a divided infusion on days 0 and 1 (treatment period). Primary endpoints were safety-related (phase I part) and efficacy-related (objective response rate [ORR] by RECIST v1.1/irRECIST; phase II part). Safety- and efficacy-related secondary endpoints were considered in both phase I/II parts.

For the full analysis set (N=8; phase I, n=3; phase II, n=5), the ORR was 50.0% (95%CI: 15.7-84.3) with best overall partial response in 4 of 8 patients according to RECIST v1.1/irRECIST. All patients experienced adverse events and 7 of 8 patients (87.5%) had adverse drug reactions but no deaths were attributed to adverse events. Cytokine release syndrome occurred in 4 of 8 patients (50.0%) but all cases recovered with prespecified treatment. Immune effector cell-associated neurotoxicity syndrome, replication competent retrovirus, and lymphocyte clonality were absent.

Adoptive immunotherapy with TBI-1301 to selectively target NY-ESO-1 positive tumor cells appears to be a promising strategy for the treatment of advanced or recurrent synovial sarcoma with acceptable toxicity.

Synovial sarcoma (SS) is one of the commonest non-rhabdomyosarcoma soft tissue sarcoma with limited treatment options in the relapsed and advanced settings. The combination of gemcitabine and docetaxel has demonstrated its role predominantly in leiomyosarcoma and pleomorphic sarcomas but has not been prospectively studied in SS. This trial assesses the efficacy, tolerability and quality of life (QoL) with this regimen in metastatic/unresectable locally advanced relapsed SS.Patients and methods This was a single-arm, two-stage, phase II, investigator-initiated interventional study among patients with metastatic or unresectable locally advanced SS who had progressed after at least one line of chemotherapy. Gemcitabine 900 mg/m2 on days 1 and 8 and docetaxel 75 mg/m2 on day 8 were administered intravenously every 21 days. The primary endpoint was 3-month progression-free rate (PFR); overall survival (OS), progression-free survival (PFS), overall response rate (ORR), safety and quality of life (QoL) constituted the secondary endpoints.Results Twenty-two patients were enrolled between March 2020 and September 2021 and the study had to be closed early due to slow accrual. The study population comprised of 18 (81.8%) patients with metastatic disease and 4 (18.2%) patients with locally advanced, unresectable disease. The most common primary sites of disease were extremity in 15 (68%) and the median number of lines of prior therapies received was 1 (range 1-4). 3-month PFR was 45.4% (95% CI 24.8-66.1) and ORR was 4.5%. Median progression-free survival (PFS) was 3 months (95% CI 2.3-3.6) and median OS was 14 months (95% CI 8.9-19.0). 7 (31.8%) patients experienced grade 3 or worse toxicities, including anemia (18%), neutropenia (9%) and mucositis (9%). QoL analysis demonstrated significant decline in certain functional and symptom scales, while financial and global health scales remained stable.Conclusion This is the first prospective study on the combination of gemcitabine and docetaxel performed specifically in patients with advanced, relapsed SS. Although the accrual of patients could not be completed as planned, the therapy did produce clinically meaningful outcomes and met its primary endpoint of 3-month PFR. This result, along with the manageable toxicity profile and stable global health status on QoL analysis, should encourage further studies.Trial registration This trial was prospectively registered under the Clinical Trials Registry of India on 26/02/2020 (Registration number: CTRI/2020/02/023612).

While the overall prognosis is generally quite satisfactory in children, adolescents and young adults with localised synovial sarcoma at first diagnosis, the outcome remains poor for patients after relapse. Conversely to the front-line standardised treatment options, patients with relapse generally have an individualised approach and to date, there is still a lack of consensus regarding standard treatment approaches. Studies on relapsed synovial sarcoma were able to identify some prognostic variables that influence post-relapse survival, in order to plan risk-adapted salvage protocols. Treatment proposals must consider previous first-line treatments, potential toxicities, and the possibility of achieving an adequate local treatment by new surgery and/or re-irradiation. Effective second-line drug therapies are urgently needed. Notably, experimental treatments such as adoptive engineered TCR-T cell immunotherapy seem promising in adults and are currently under validation also in paediatric patients.