SAN DIEGO, May 27, 2025 /PRNewswire/ -- Phanes Therapeutics, Inc. (Phanes), a clinical stage biotech company focused on innovative drug discovery and development in oncology, announced today that the first patient has been dosed in the clinical study of mavrostobart (PT199) in combination with chemotherapy.
Mavrostobart is an anti-CD73 monoclonal antibody with a differentiated mechanism of action and is designed to counter the adenosine-mediated immunosuppressive tumor microenvironment (TME). Mavrostobart fully inhibits the enzyme activities of both soluble and membrane-bound CD73, unlike several other anti-CD73 antibodies which exhibit incomplete inhibition. Moreover, at higher concentrations, no loss of inhibition or "hook effect" is observed with mavrostobart. Hence, mavrostobart addresses the limitations of current CD73 inhibitors and is expected to increase antitumor immune activation, and potentially offer a new treatment option for cancer patients.
The multi-center Phase I/II clinical trial of mavrostobart (NCT05431270), known as the MORNINGSTAR study, is currently evaluating the safety, tolerability, pharmacokinetics and preliminary efficacy of mavrostobart alone and in combination with a PD-1 Inhibitor or chemotherapy. A Phase I clinical trial of mavrostobart is also ongoing in China (CTR20242381).
ABOUT PHANES THERAPEUTICS
Phanes Therapeutics, Inc. is a clinical stage biotech company focused on innovative drug discovery and development in oncology. Currently, it is conducting three Phase I/II clinical trials, including the MORNINGSTAR study with its best-in-class monoclonal antibody (mAb) program, mavrostobart (PT199), the TWINPEAK study with spevatamig (PT886) and the SKYBRIDGE study with peluntamig (PT217). Both spevatamig and peluntamig are first-in-class bispecific antibodies and have been granted orphan drug designations as well as Fast Track designations by the FDA.
The company has built a strong pipeline by leveraging its proprietary technology platforms: PACbody®, SPECpair® and ATACCbody® to develop novel biologics that address high unmet medical needs in cancer.
For more information about Phanes Therapeutics, please visit www.phanesthera.com
For business development or media inquiries, please contact bd@phanestx.com or media@phanestx.com, respectively.
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SOURCE Phanes Therapeutics, Inc.
