QSAM Biosciences Completes Enrollment of Initial Cohort in its Phase 1 Study of CycloSam Targeting Metastatic Bone Cancer


QSAM Biosciences Inc. recently announced the completion of enrollment in the first participant grouping (cohort) of its Phase 1 study evaluating CycloSam in the treatment of bone cancer. The last participant dosed was a breast cancer patient with active metastatic bone cancer.

QSAM’s study is a multiple center, open label, dose escalation clinical trial intended to determine the maximum tolerated dose of CycloSam in patients, and also assess early safety and efficacy signals. The completed cohort of three participants received the lowest dosage of CycloSam in the study. The total dosage of the active radioisotope Samarium-153 to be received by the second cohort, expected to commence in early Q2 2023, will be 50% higher.

“Completion of our first cohort of patients is an important milestone for QSAM,” said Douglas R. Baum, CEO. “We are pleased with the early results, and are looking forward to continuing enrollment in subsequent cohorts in this important clinical trial evaluating the early safety and efficacy of CycloSam in patients with metastatic bone cancer.”

The most recent participant in QSAM’s clinical trial was a patient with breast cancer that had metastasized to the bone, a serious and life-threatening disease for which there is an unmet need by patients and an area of high interest by management for the clinical trials and product development of CycloSam. The only two commercially available radiotherapies for bone cancer, to management’s knowledge, are only FDA approved for use in men who have bone metastases from prostate cancer. CycloSam, which delivers its radioactive payload using a chelant that is highly targeted to high calcium turnover in bone and bone tumors, is currently being studied in a clinical trial for both male and female patients with bone cancer that has metastasized from the breast, lungs, prostate, or other organs, as well as patients with cancer that has originated in the bone, such as osteosarcoma and Ewing’s Sarcoma – diseases that mostly affect children and young adults.

Adults with bone cancer that has migrated or metastasized from the breast, lung, or prostate is common and frequently fatal. QSAM is dedicated to developing its Cyclosam product for this important patient population, and patients with any of these bone cancer types are eligible for this clinical trial. Osteosarcoma, while still a rare pediatric disease, is the most common form of bone cancer in children and young adults (ages 15-39) with primary high-grade bone malignancy, and Ewing’s Sarcoma bone cancer is the second most common form of bone cancer in children. According to the Cancer Facts & Figures 2021 produced by the American Cancer Society there are about 400,000 new cases of malignant bone metastasis (which includes approximately 14% of the 265,000 women diagnosed with breast cancer each year), and 3,610 new cases of primary bone cancer diagnosed in the US each year.

QSAM Biosciences, Inc. is developing next-generation nuclear medicines for the treatment of cancer and related diseases. QSAM’s initial technology, CycloSam (Samarium-153 DOTMP), is a clinical-stage bone-targeting radiopharmaceutical developed by IsoTherapeutics Group LLC, pioneers in the nuclear medicine space who also developed the FDA-approved Quadramet (Samarium-153 EDTMP) radiopharmaceutical product. The QSAM team has designed the Cyclosam product with the goal of overcoming the limitations of the Quadramet (Samarium-153 EDTMP) product’s FDA-approved indications. QSAM is led by an experienced executive team and board of directors that have completed numerous FDA approvals and multiple successful biotech exits.

CycloSam has demonstrated preliminary safety and efficacy in animal studies and a single patient FDA-cleared human trial performed in 2020 at the Cleveland Clinic. This nuclear technology uses low specific activity Samarium-153 (resulting in far less long-lived Europium impurities) and DOTMP, a chelator which is believed to reduce or eliminate off-target migration and targets sites of high bone turnover, making it, in management’s opinion, an ideal agent to treat primary and secondary bone cancers. Since CycloSam delivers targeted radiation selectively to the skeletal system and to bone tumors, it is also believed to be a great potential candidate for future effectiveness clinical trials in bone marrow ablation as preconditioning for bone marrow transplantation, as well as its future clinical trials in procedures to reduce external beam radiation to bone tumors. This multi-patented drug candidate utilizes a radioisotope previously approved by the FDA combined with a novel chelant, DOTMP, that has demonstrated preliminary increased efficacy and decreased side effects in animal models and veterinary treatment of bone cancer in dogs. Further, CycloSam utilizes a streamlined, just-in-time manufacturing process that is already in place. Given these factors, management believes there is a strong pathway to commercialization for CycloSam.