The FDA has granted Orphan Drug Designation to 7MW3711, a novel antibody-drug conjugate (ADC) targeting B7-H3, for the treatment of small cell lung cancer (SCLC). This designation aims to incentivize the development of therapies for rare diseases, offering Mabwell potential benefits such as market exclusivity and tax credits.
7MW3711 is being developed utilizing Mabwell's innovative IDDC™ platform. The ADC is composed of an innovative antibody molecule, a novel linker, and a novel payload Mtoxin™ (TOP1i), designed to target antigens expressed on solid tumors. Preclinical data indicates that 7MW3711 exhibits superior tumor-killing effects compared to other ADCs in its class and has a manageable safety profile.
Mechanism of Action
Upon entering the body, 7MW3711 specifically binds to antigens on the tumor cell membrane surface. The ADC is then internalized and transported to the lysosome, where it releases a cytotoxic drug, leading to tumor cell apoptosis. This targeted approach aims to minimize off-target effects and maximize efficacy.
Clinical Development
Currently, 7MW3711 is undergoing evaluation in an open-label, multicenter, phase 1/2 study (NCT06008366) for the treatment of advanced solid tumors. The trial includes a dose-escalation phase (part 1) and a dose-expansion phase (part 2). Part 1 focuses on assessing the safety and tolerability of 7MW3711, as well as determining the maximum tolerated dose (MTD) and/or the recommended phase 2 dose (RP2D) in patients with advanced solid tumors.
Eligible patients are aged 18 to 75 with an ECOG performance status of 0 or 1 and a life expectancy of at least 3 months. They must have histologically or cytologically confirmed locally advanced or metastatic solid tumors that have progressed following their last treatment or have progressed on or after standard therapies. Patients must also be intolerant to approved therapies or lack sufficient standard therapies.
The primary endpoints of part 1 include evaluating the incidence of adverse events and identifying the MTD/RP2D of 7MW3711. For part 2, the primary endpoint is the overall response rate (ORR) based on RECIST v1.1. Secondary endpoints include ORR, incidence and seriousness of adverse events (AEs) and serious AEs, evaluation of area under the plasma concentration vs time curve, and evaluation of 7MW3711's half-life time.
Mabwell's IDDC Platform
Mabwell's IDDC platform is a next-generation ADC site-specific conjugation technology composed of multiple systematic core patented technologies, including the site-specific conjugation process DARfinity, the site-specific linker IDconnect, the novel payload Mtoxin, and the conditional release structure LysOnly.
Mabwell is also developing other ADCs, including 9MW2821, a novel Nectin-4-targeting ADC being assessed in a phase 3 trial for patients with urothelial carcinoma. In May 2024, 9MW281 was also granted ODD in esophageal cancer.
