Alligator Bioscience and Aptevo Therapeutics have announced the “may proceed” notification for the ALG.APV-527 investigational new drug application (IND).

The notification allows the companies to initiate clinical trials evaluating the compound for the treatment of 5T4-expressing tumor antigens in multiple solid tumor types. They are moving rapidly to initiate a multi-center Phase 1 trial in the US, they state in a press release.

Alligator’s third asset in clinical development

ALG.APV-527 is an antibody with dual function: tumor-binding and 4-1BB immunomodulatory agonist effects. This has the potential to be clinically important because 4-1BB has the ability to stimulate the immune cells (antitumor-specific T cells) involved in tumor control, making immune cell stimulation through 4-1BB a particularly compelling target for cancer immunotherapy. Preclinical results have highlighted the differentiated design of the molecule that minimizes systemic immune activation, allowing for highly efficacious tumor-specific responses as demonstrated by potent activity in in vitro models, states the company.

The tumor-binding function of ALG.APV-527 targets the 5T4 tumor-associated antigen. 5T4 is a protein expression in multiple solid tumor types and limited expression in normal tissues, making 5T4 a compelling target molecule for cancer therapy.

“This new IND also demonstrates our ability to bring innovative antibodies to the clinic.”

“This IND clearance marks an important step in the development of ALG.APV-527 and is a testament to the strength of our partnership with Aptevo. This new IND also demonstrates our ability to bring innovative antibodies to the clinic,” says Søren Bregenholt, CEO of Alligator Bioscience. “This compound will now become Alligator’s third asset in clinical development. We are looking forward to initiating this Phase 1 first in human study in multiple solid tumors and further investigating the indications where it is most effective.”

Photo of Søren Bregenholt: Alligator Bioscience