ABL Bio has announced that its licensed antibody-drug conjugate (ADC) candidate achieved complete response (CR) in all patients during early-stage clinical trials for first-line treatment of diffuse large B-cell lymphoma (DLBCL).
On August 28, ABL Bio reported that its global partner, CStone Pharmaceuticals, released clinical data from the Phase 1b trial of CS5001 (ABL202/LCB71) in its semi-annual business report.
CS5001 is an ADC co-developed with Ligand Pharmaceuticals, based on ABL Bio’s ROR1 monoclonal antibody, which has been licensed to CStone.
CStone administered CS5001 at doses ranging from 40 to 90 µg/kg in combination with the standard R-CHOP regimen to 31 patients with first-line DLBCL.
The trial yielded impressive results, with a 100% complete response rate across all dosage groups. Additionally, the objective response rate (ORR) reached 100% among all patients. Notably, even the lowest dose of 40 µg/kg demonstrated CR, suggesting that anti-cancer efficacy may be maintained at reduced doses.
Based on these promising results, CStone has decided to temporarily pause the ongoing trial. This will allow for a comprehensive evaluation of CS5001’s efficacy and safety profile, as well as determination of the optimal dosage and administration schedule.
This pause is not a termination of clinical development, but rather a strategic move to optimize future development based on the encouraging anti-cancer effects and tolerability observed thus far.
CS5001 is designed to target ROR1 on cancer cell surfaces for drug delivery. ABL Bio developed this compound in partnership with Ligand and is now overseeing global clinical development after licensing it to CStone.
While these results are promising, caution is advised in their interpretation due to the early stage of research. With only 31 patients involved in this Phase 1b trial, further follow-up is necessary to confirm the durability of response and long-term safety profile. The replication of these results in subsequent clinical trials will be crucial in assessing CS5001’s commercial viability.
Dr. Lee Sang-Hoon, Chief Executive Officer (CEO) of ABL Bio, expressed optimism about the findings: It’s encouraged by the 100% complete response rate observed across all dosage groups from 40 to 90 µg/kg, along with a 100% overall objective response rate. He added that CStone plans to optimize the dosage and administration schedule before swiftly advancing to the next phase of development.
ABL Bio, founded in February 2016 by CEO Sang-Hoon Lee and former researchers from Hanwha Chemical’s Bio Division, specializes in developing dual-antibody drugs. The company has focused on creating immunotherapy drugs and treatments for degenerative brain diseases using its proprietary Grabody dual-antibody platform.
Since initiating domestic clinical trials for ABL001 in 2017, ABL Bio has expanded its reach through technology transfers and collaborations. In 2018, the company inked technology transfer and co-development agreements with firms like Dong-A ST and I-Mab. Just two years and nine months after its inception, ABL Bio went public on the KOSDAQ in December 2018. The company has since broadened its partnerships with global pharmaceutical giants such as Sanofi and CStone, extending its focus beyond dual antibodies to next-generation antibody therapies, including dual-antibody ADCs.
