Benzinga | Feb 5, 2021 07:33AM EST

Moleculin Biotech Announces Preclinical Study In Animals Showing 100% Survival Achieved In Osteosarcoma Lung Metastases Animal Model Of Annamycin Drug

VANCOUVER, British Columbia, Feb. 05, 2021 (GLOBE NEWSWIRE) -- WPD Pharmaceuticals Inc. (CSE:WBIO)(FSE: 8SV1) (the "Company" or "WPD") a clinical-stage pharmaceutical company, is pleased to announce that that Moleculin Biotech Inc. (NASDAQ:MBRX) ("Moleculin"), the company that sublicenses the compound Annamycin to WPD for 29 countries mainly in Europe, announced that a preclinical study in animals demonstrated a potentially significant therapeutic benefit of Annamycin against metastatic osteosarcoma. The Moleculin press release of February 2, 2020 states, "This appears to be the result of the high cytotoxic potential of Annamycin previously demonstrated in vitro against sarcoma cells in combination with its high uptake by the lungs where the tumors in this study are localized. Computerized tomography (CT) scans demonstrated that animals treated with Annamycin exhibited significant suppression of tumor growth and not a single death was observed in the treated animals, whereas significant tumor burden contributed to the rapid death of 90% of untreated animals. While the study continues, as of day 130, the survival rate for animals treated with Annamycin was 100%, compared with only 10% for untreated animals.



Osteosarcoma is among a class of tumors that initiate in the bone of patients, with bone-related sarcomas representing the second most common form of sarcoma after soft tissue sarcoma. While many bone sarcomas can be addressed through surgical removal, it is estimated that as many as 40% of bone sarcomas will eventually metastasize to the lungs, where treatment can become more problematic. Researchers have more recently referred to the lungs and certain other vital organs as "sanctuary sites" for cancer where tumors can develop out of reach from conventional chemotherapies.

Once metastasized to the lungs, if tumors cannot be surgically removed, the primary chemotherapy regimen is the anthracycline doxorubicin (also known as Adriamycin). While 10% to 30% of patients with sarcoma lung metastases may initially respond to doxorubicin, most will relapse leaving the majority of these patients without an alternative chemotherapy. Moleculin recently announced findings from its sponsored research showing that doxorubicin has a limited ability to accumulate in the lungs of animals, which may help explain its limited efficacy in this sanctuary site. Treatment options are further limited because of the inherent cardiotoxicity of currently approved anthracyclines, including doxorubicin, which limits the amount of anthracycline that can be given to patients.

Annamycin is a "next generation" anthracycline that has recently been shown in animal models to accumulate in the lungs at up to 34 times the level of doxorubicin, which may account for the 100% survival rate attained in this most recent osteosarcoma lung metastases study. Importantly, Annamycin has also demonstrated a lack of cardiotoxicity in recently conducted human clinical trials of Annamycin for the treatment of acute myeloid leukemia, so the use of Annamycin may not face the same dose limitations imposed on doxorubicin.

Moleculin recently announced that the FDA has allowed the Company's request for investigational new drug (IND) status in order to study Annamycin for the treatment of soft tissue sarcoma metastasized to the lungs. In addition, the FDA granted Orphan Drug Designation for Annamycin for the treatment of soft tissue sarcomas.

Moleculin also stated that it expects that one, and potentially two, clinical trials in sarcoma lung metastases should commence in 2021."

WPD has not conducted its own independent confirmation testing of Annamycin and is relying solely on the information contained in Moleculin's news releases dated February 2, 2021 in providing this information to WPD's shareholders.