OS Therapies Inc (NYSE-A:OSTX) announced encouraging preclinical results for its first therapeutic candidate targeting ovarian cancer.
Preclinical data derived from tests conducted on KB and IGROV-1 mouse models of ovarian cancer demonstrated strong antitumor activity, the company said in a statement.
The therapy is based on the company’s proprietary tunable Antibody Drug Conjugate (tADC) platform, which combines a folate receptor alpha (FRA) targeting molecule with hexa-exatecan payloads linked via OS Therapies’ SiLinker technology.
SiLinker is designed to maximize the therapeutic effect while minimizing off-target toxicity by releasing multiple therapeutic agents within the tumor microenvironment, which is characterized by a lower pH than healthy tissues.
In the KB model, animals treated with OST-tADC-FRA-H exhibited significantly reduced tumor growth compared to controls, OS Therapies said in a statement. By Day 20, treated mice had an average tumor volume of 10 cubic millimeters, compared to 1,000 cubic millimeters in untreated animals.
By Day 40, no tumor growth was observed in the treated group, while control animals had succumbed to the disease.
Similarly, in the IGROV-1 model, treated animals saw an average tumor size of 40 cubic millimeters by Day 50, compared to 400 cubic millimeters in the control group. Additionally, animals treated with OST-tADC-FRA-H maintained their bodyweight, indicating minimal systemic toxicity.
"With the ability to link multiple payloads, including with different therapeutic agent combinations, we are potentially revolutionizing the way antibody drug conjugates will be constructed in the future,” said Colin Goddard, tADC founder and member of the OS Therapies ADC Advisory Board.
The animal proof of concept experiment for tADC “really opens the door” to creating multiple therapeutic candidates for preclinical and clinical evaluation, added Borys Shor, member of the OS Therapies ADC Advisory Board.
"Now that we have this animal data and have begun the process of creating multiple other tADC constructs, we are able to meaningfully engage with potential collaborators and partners on helping them improve the way their ADC combinations are delivered, in addition to developing our own candidates in the future."
The global ADC market was estimated at $11.29 billion in 2023 and is projected to grow at a compound annual growth rate of 9.2% through 2030, according to Grandview Research.
The global market for ovarian cancer drugs is expected to follow a similar trajectory, reaching $5.6 billion by 2030.