AIM ImmunoTech Inc. (NYSE: American AIM) (“AIM” or the “Company”), an immuno-pharma company focused on the research and development of therapeutics to treat multiple types of cancers, immune disorders, and viral diseases, including COVID-19, the disease caused by the SARS-CoV-2 virus, today announced the presentation of data from the ongoing Phase 2a clinical study at Roswell Park Comprehensive Cancer Center evaluating AIM ImmunoTech Inc. drug candidate, Ampligen® (also known as rintatolimod) as a component of treatment for colorectal cancer metastatic to the liver at the American Association for Cancer Research (AACR) Annual Meeting 2022, being held April 8-13, 2022, in New Orleans, Louisiana. The presented research was led by Roswell Park medical oncologist Sarbajit Mukherjee, MD, MS, in collaboration with senior investigator Pawel Kalinski, MD, PhD, Chair of Immunology at Roswell Park.
Title:Initial results of a phase II study evaluating a chemokine-modulatory (CKM) regimen in patients with colorectal cancer metastatic to the liver Presenter: Sarbajit Mukherjee, MD, MS
Based on preclinical data and previous reports showing the prognostic value of intratumoral CD8+ T cell (CTL) in colorectal cancer (CRC) outcomes, it was hypothesized that systemic infusion of the combination of IFNα-2b with Ampligen (selective TLR3 ligand for i.v. use) could reprogram the local balance between the CTL- and regulatory T cell (Treg)-attracting chemokines and the resulting patterns of immune infiltrates in liver tumors. For the study, recurrent/metastatic CRC patients with unresectable liver metastases amenable to biopsy were eligible. Patients had prior treatment (Rx) with fluoropyrimidine, irinotecan, oxaliplatin, and an anti-EGFR targeted therapy (if RAS wt), or contra-indication to such. Patients received IFNα-2b IV (20 million units/m2 IV daily) and Ampligen (200 mg IV daily) plus oral celecoxib (200 mg twice daily) on days 1, 2, 3, 8, 9, 10, 15, 16, and 17. Response assessment was done via liver biopsies (pre-Rx and on day 24 ± 4 days) and CT imaging (RECIST v1.1) on Day 46. The primary endpoint was the change in CD8+ T-cells before Rx, with that seen post-Rx (measured by quantitative RT-PCR as a ratio of CD8α to a housekeeping gene, HPRT). With a sample size of N=12 evaluable pts, the study design had a 90% power to detect a 0.77 standard deviation increase (pre- to post Rx) at a significance level of 0.1. Nineteen patients with microsatellite stable (MSS) CRC were enrolled in the study between Apr 2018 and Oct 2020, and 12 were evaluable for the primary endpoint. “The primary endpoint of this study, a significant increase in CD8a expression post-treatment, along with increases in CTL-attracting chemokines coupled with a decrease in a key Treg/MDSC attractant indicate a positive immune effect on the tumor microenvironment and suggest this CKM approach has the potential to increase tumor responses to checkpoint inhibitors”, commented David R. Strayer, MD. The study's primary endpoint was met, evidenced by increased CD8a expression post-treatment (p=0.046). The expression of CTL-attracting chemokines CCL5 (p=0.08), CXCL9 (p=0.05), and CXCL10 (p=0.06) were increased, while expression of the Treg/MDSC attractant CXCL12 (p=0.07) was decreased post-treatment. Median OS was 10.5 (90% CI 2.2-15.2) months, and the median PFS was 1.5 (90% CI 1.4, 1.8) months.
No tumor responses were seen. The treatment was well tolerated. Of all enrolled patients (N=19), adverse events were noted in 74% of patients, with the most common being fatigue (58%). Grade 3 or higher adverse events were rare (5%).