Ascletis Pharma Inc., an innovative R&D-driven biotech company, has recently announced that it has dosed the first patient in a Phase 1 clinical trial with the ASC61, an oral PD-L1 small molecule inhibitor prodrug, which can be used to treat advanced solid tumors.

Imperative to note that the U.S. Phase I trial is a dose-escalation study conducted to examine the tolerability and safety of ASC61 as well as outline the MTD (maximum tolerated dose) and RP2D (recommended Phase 2 dose) of ASC61 to be given to patients who have advanced solid tumors and suffer from disease progression throughout or after the standard therapy.

For the uninitiated, ASC61 is an oral PD-L1 small molecule inhibitor prodrug developed with Ascletis' in-house technology. 

ASC61-A is a potent and selective inhibitor that blocks the interaction of PD-1/PD-L1 by inducing PD-L1 internalization and dimerization.

Being a single agent, the drug showcased considerable anti-tumor efficacy in numerous animal and humanized mouse models.

According to the preclinical studies, ASC61 offers adequate safety and pharmacokinetic profiles in animal models.

Compared to the PD-1/PD-L1 antibody injections, ASC61 offer several benefits, which include:

• Improved patient compliance with safe and easy administration with no requirement of visiting the hospital for injections
• Managing immune-related adverse effects (irAEs) easily with dose adjustment
• Offers ease of all oral combination treatments with other oral anti-tumor drugs
• Increased permeability to distribute into targeted tissues

Speaking on the development, Dr. Jinzi J. Wu, Founder, CEO & Chairman of Ascletis, mentioned that the significant disadvantages of therapeutic antibodies include poor permeability and Immunogenicity of tumor tissues, which can result in lowering the response rate of PD-1/PD-L1 antibodies.

ASC61, a highly segregated small molecule PD-L1 inhibitor, offers few advantages over antibodies and showcases favorable preliminary safety and efficacy profiles in preclinical studies.

Wu further stated that the firm is still advancing the studies of ASC61 to offer more options for patients suffering from advanced solid tumors.

Source Credit - https://www.prnewswire.com/news-releases/ascletis-announces-first-patient-dosed-in-the-us-phase-i-clinical-trial-of-oral-pd-l1-small-molecule-inhibitor-prodrug-asc61-for-treatment-of-advanced-solid-tumors-301601167.html