1757P - Proceedings of the think tank for osteosarcoma medical advisory board meeting

Background

In the past 4 decades, advances in cancer therapy have not resulted in a significant increase in overall survival for osteosarcoma, with a 5-year survival rate of 70% for localized disease and 30% for metastatic disease, and a chance of recurrence ranging from 30-40%, usually within two years (1). For extra-skeletal osteosarcoma, the prognosis is somewhat worse with 47% of patients developing distant metastases and a 5-year survival rate of 62%.

Methods

The goal of the Think Tank is to develop a strategic approach to reduce the chance of osteosarcoma recurrence from 30-40% to as close to 0% as possible. A Think Tank for Osteosarcoma Medical Advisory Board Meeting, comprised of key opinion leaders in the fields of sarcoma, gene therapy, immunotherapy and integrative medicine was held at the Shutters on the Beach hotel, 1 Pico Blvd., Santa Monica CA 90405 on February 2-3, 2024.

Results

Osteosarcoma metabolism and the genomic instability of osteosarcoma, immunotherapy for osteosarcoma, CAR-T cell therapy, DeltaRex-G tumor-targeted gene therapy, repurposed drugs, alternative medicines, and personalized medicine were discussed. For the purpose of preventing recurrence, DeltaRex-G was the only treatment that was voted upon by all, and gained favorable recommendations from 10 of 12 (6 of 8 medical oncologists) attendees with one agreeing only if it would not take away from other patients with more advanced disease. Of those who opposed, one recommended its use only in a metastatic setting and one recommended that a Phase II randomized study of 60-80 high-risk osteosarcoma subjects be conducted which may lead to accelerated approval of DeltaRex-G in the US.

Conclusions

(1) No intervention has been demonstrated to improve survival in a clinical trial; (2) The consensus was that DeltaRex-G may be given up to one year; (3) Phase II/3 randomized studies of DeltaRex-G should be conducted; (4) A personalized approach using drugs with minimal toxicity could be tried; (5) Repurposed drugs and alternative therapies should be tested in mouse models of osteosarcoma; (6) Unmodified IL-2 primed Gamma Delta (NK) cell therapy may be used to prevent recurrence; (7) Rapid development of CAR-T cell therapy is recommended; and (8) An institute for the study of osteosarcoma is needed.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

Sarcoma Oncology Research Center.

Funding

Aveni Foundation.

Disclosure

E.M. Gordon: Financial Interests, Personal, Member of Board of Directors: Aveni Foundation. All other authors have declared no conflicts of interest.