Alligator Bioscience and Aptevo Therapeutics to Present Additional Positive Interim Phase 1 Data Evaluating ALG.APV-527 Monotherapy in Multiple Solid Tumor Types, at SITC 2024

LUND, SWEDEN and SEATTLE WA / October 29, 2024 / Alligator Bioscience AB (“Alligator”) (ATORX) and Aptevo Therapeutics (“Aptevo”) (Nasdaq: APVO) today announced that new, positive interim data from the dose escalation phase of their Phase 1 trial evaluating ALG.APV-527 will be presented in a poster session on Friday, November 8, 2024, at the Society for Immunotherapy of Cancer 2024 (SITC), taking place November 6th – 10th, 2024 in Houston, Texas.

Presentation Details
Poster number: #673
Title: Preliminary results from a phase I dose escalation study of ALG.APV-527, a 5T4×4-1BB bispecific antibody, in patients with advanced solid tumors demonstrate favorable safety and biological activity
Presenter: Thomas Marron, MD, PhD
Date/Time: Friday, November 8th from 12:15-1:45 and 5:30-7:00 PM US Central time.

About the Trial
The ALG.APV-527 Phase 1 trial is a multi-center, multi-cohort, open-label dose-escalation trial that will include administration of ALG.APV-527 up to six escalating dose levels in a 3+3 design*. The trial is enrolling adult patients with multiple solid tumor types/histologies likely to express the 5T4 antigen. ALG.APV-527 will be given intravenously once every two weeks. The trial will assess the safety and tolerability, pharmacokinetics, pharmacodynamics and preliminary anti-tumor activity of ALG.APV-527.

*The 3+3 design proceeds in cohorts of three patients treated at increasing dose levels. Dose escalation stops when at least two out of three or six patients experience dose limiting toxicities (DLTs) at that dose level.

About ALG.APV-527
ALG.APV-527 is a bispecific conditional 4-1BB agonist, only active upon simultaneous binding to 4-1BB and 5T4. This has the potential to be clinically important because 4-1BB can stimulate the immune cells (antitumor-specific T cells and NK cells) involved in tumor control, making 4-1BB a particularly compelling target for cancer immunotherapy. 5T4 is an oncofetal tumor associated antigen overexpressed on numerous solid tumors including non-small-cell lung carcinoma (NSCLC), breast, head and neck, cervical, renal, gastric, and colorectal cancer.

Updated 2024-10-29