OBI Pharma announced the initiation of a Phase 1/2 clinical trial for OBI-902, a novel antibody-drug conjugate (ADC) targeting TROP2 (Trophoblast cell-surface antigen 2) in patients with advanced solid tumors. The Taiwan-based clinical-stage oncology company marks a significant milestone as OBI-902 becomes the first ADC developed using their proprietary GlycOBI® ADC enabling technology to enter human testing.
The study will enroll patients with advanced solid tumors to verify the safety, pharmacokinetics, and preliminary efficacy profile of OBI-902. Apostolia M. Tsimberidou, MD, PhD, of MD Anderson Cancer Center in Houston, Texas, serves as the lead investigator for the trial.
Novel ADC Technology Platform
OBI-902 represents a breakthrough in ADC design, utilizing OBI's proprietary GlycOBI® platform for site-specific glycan conjugation. The ADC carries a potent topoisomerase I inhibitor payload with a drug-antibody ratio (DAR) of 4, targeting TROP2, an antigen highly expressed in various solid tumors including breast, biliary, ovarian, gastric, and other cancer types.
The GlycOBI® technology operates in a "Plug and Play" format, compatible with any antibodies, linkers, and payloads in drug-antibody ratios up to 16. The platform utilizes OBI's proprietary dual-function enzyme (EndoSymeOBI®) and linker technology (HYPrOBI®) to manufacture homogenous ADCs through an efficient and scalable process under GMP conditions.
Preclinical Evidence and Regulatory Approval
At the 2025 American Association for Cancer Research (AACR) meeting, OBI presented compelling preclinical data demonstrating OBI-902's enhanced linker-payload stability, favorable pharmacokinetics, and superior and durable antitumor activities compared to other TROP2 ADCs in numerous in-vitro and animal studies.
The conjugation process of GlycOBI® avoids disrupting the antibody structure and ensures the ADC maintains similar biophysical characteristics to the native antibody. Additionally, OBI's linker technology improves conjugation efficiency of the payload and reduces aggregation propensity, providing manufacturing advantages for ADC products.
The U.S. FDA cleared the investigational new drug (IND) application for OBI-902 on April 30, 2025, enabling the current clinical trial initiation.
Strategic Partnerships and Commercial Rights
OBI has licensed the TROP2 targeting antibody from Biosion, Inc. since December 2021, holding exclusive rights worldwide except in China. The company maintains worldwide commercial rights to OBI-902, with the exception of rights pertaining to the antibody in China. Notably, OBI has not granted Biosion any rights to OBI ADCs, including the OBI-902 product.
Expanding ADC Pipeline
"We are excited to initiate this first in human study of OBI-902. This is an important company milestone and highlights our commitment to building and strengthening the novel OBI Pharma pipeline," said Heidi Wang, Ph.D., OBI Pharma's Chief Executive Officer. "We also look forward to obtaining clinical data from this first GlycOBI®-conjugated ADC."
OBI's ADC pipeline extends beyond OBI-902, including the first-generation cysteine-based TROP2 ADC OBI-992, and next-generation candidates such as OBI-904 (Nectin-4), bispecific single payload (HER2 x TROP2), and bispecific dual payload (cMET x HER3) ADCs. The company has also developed the ThiOBI® platform to enable irreversible cysteine-based conjugation, broadening the applicability of their linker technology.
The clinical trial initiation represents a crucial step forward for OBI Pharma, established in 2002 and headquartered in Taiwan, as the company advances its mission to develop novel therapeutic agents for patients with high unmet medical needs in oncology.
