Phanes Therapeutics Announces First Patient Dosed in Phase 1 Study of PT199 for Advanced Solid Tumors

SAN DIEGOAug. 23, 2022 /PRNewswire/ — Phanes Therapeutics, Inc. (Phanes), an emerging leader in innovative discovery research and clinical development in oncology, announced today that the first patient has been dosed in the phase 1 clinical study (NCT05431270) of PT199, an anti-CD73 monoclonal antibody (mAb) for the treatment of multiple advanced solid tumors.

PT199 is an anti-CD73 mAb with a differentiated mechanism of action and is designed to counter the adenosine-mediated immunosuppressive tumor microenvironment (TME). PT199 fully inhibits both soluble and membrane-bound CD73, unlike some other CD73 inhibitors which exhibit incomplete inhibition. Moreover, at higher concentrations, no loss of inhibition or “hook effect” is observed with PT199. Hence, PT199 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 CD73 pathway represents a very promising target for addressing the immunosuppressive TME and we are pleased to open this study and bring this potential best-in-class mAb to cancer patients who have few treatment options.” said Dr. Ming Wang, Founder and CEO of Phanes Therapeutics.

The multi-center Phase I clinical trial of PT199 is evaluating the safety, tolerability, pharmacokinetics, pharmacodynamics, and preliminary efficacy of PT199, alone and in combination with a PD-1 inhibitor, in patients with locally advanced or metastatic solid tumors that have progressed after all available standard therapy or for which standard therapy has proven to be ineffective, intolerable, or is considered inappropriate.  Enrollment in the trial is open to individuals aged 18 years and older who have measurable disease with at least 1 lesion amenable to response assessment per RECIST 1.1 criteria, adequate organ function, and an ECOG performance status of 0 to 1.

For more information on the study please visit (NCT05431270).

About Phanes Therapeutics

Phanes Therapeutics, Inc. is a biotech company focused on innovative drug discovery in oncology. Based in San Diego, California, the company’s management team members previously held senior managerial and R&D positions in leading global pharmaceutical and biotech companies with extensive experience in R&D and commercialization. The company’s bispecific antibody platform is PACbody™, a proprietary approach for constructing native IgG-like bispecific antibodies, SPECpair™, which allows mAb-like manufacturability of bispecific antibodies with native IgG-like structures, and ATACCbody™, a proprietary technology for targeting solid tumors using immuno-oncology molecules with modulated activities and thus minimal risk of cytokine release syndrome.

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