A Phase 2 Pilot Study to Evaluate the Safety and the Anti-Tumour Activity of the Myc Inhibitor OMO-103 Administered Intravenously in Patients With Advanced High-Grade Osteosarcoma
This is an open-label, unicentric, single-arm Phase 2 pilot study to serve as a proof-of-concept of OMO-103 safety and activity in patients with advanced high-grade osteosarcoma. Patients will be treated at the RP2D (6.5 mg/kg as a weekly IV infusion) of OMO-103 to estimate anti-tumour activity and further characterise the safety, tolerability, PK, and PD of OMO-103 in advanced high-grade osteosarcoma patients. Ten (10) evaluable patients will be enrolled. At least 30% of patients will be \<18 years old. The first three patients 12-15 years of age will undergo additional safety monitoring. Patients will be treated until progression by RECIST v1.1 or intolerable toxicity.
• Provision of signed and dated informed consent form.
• Age ≥12 years at time of informed consent.
• Histologically proven, advanced high-grade osteosarcoma not suitable for local treatments with curative intent
• Confirmed disease progression by radiological report to at least one line of standard chemotherapy containing cisplatin and anthracycline, and no more than 2 previous lines.
• Measurable disease as per RECIST v1.1 criteria and documented by CT/MRI (Appendix 1 - RECIST Response Criteria). NOTE: Lesions to be used as measurable disease for the purpose of response assessment must either:
∙ not reside in a field that has been subjected to prior radiotherapy, or
‣ have demonstrated clear evidence of radiographic progression since the completion of prior radiotherapy and prior to study enrolment.
• Provision of a newly obtained tumour biopsy (either from the primary tumour or from metastases) during screening and on-treatment from all patients \>16 years of age. Notes:
‣ The identified lesion to be biopsied should not have been previously irradiated and should not be the only lesion being used as a measurable-disease target lesion for objective response assessment. Patients must have tumour lesions that can be accessible for biopsy with acceptable clinical risk in the judgement of the Investigator.
⁃ In case a patient has had a tumour biopsy in the previous 6 months and a paraffin block is available, a new biopsy does not need to be done at Screening (if they have received no treatment after biopsy).
• Documented progression on or following the last line of therapy.
• ECOG performance status 0-2 (Appendix 2 - Performance Status Criteria).
• Life expectancy of ≥ 12 weeks as estimated by the treating physician.
⁃ Resolution of all acute, reversible toxic effects of prior therapy or surgical procedure to Grade ≤1 (except alopecia and peripheral neuropathy to Grade ≤2).
⁃ Adequate organ function.
⁃ If not postmenopausal or surgically sterile, female patients and female sexual partners of male patients must be willing to use at least one highly effective method of birth control (hormonal contraception, IUD, abstinence, condom) for at least a menstrual cycle before and for 3 months after last study drug administration.