New autotherapy shows promise for treating advanced thyroid cancer

New autotherapy shows promise for treating advanced thyroid cancer

A new chimeric antigen receptor (CAR) therapy called AIC100 that targets the ICAM-1 protein showed encouraging responses and an acceptable safety profile in patients with two types of advanced thyroid cancer, according to researchers at the University of Texas MD Cancer Center.

Results from the first-in-human Phase I trial were presented today at the American Association for Cancer Research (AACR) 2025 Annual Meeting by principal investigator Samer SROUR, MB CHB, associate professor of stem cell transplantation and cell therapy.

The potentially promising early results in anaplastic thyroid cancer (ATC) and relapsed/refractory poorly differentiated thyroid cancer (PTDC) – which have limited treatment options and poor prognosis – suggest the benefits of CAR T cell therapies for patients with solid tumors. In nine patients who received dose 2 or 3, it was observed that 22% had significant tumor shrinkage and 56% had control of their disease.

The responses observed in the two dose cohorts were encouraging and provide evidence of the potential of AIC100 in the treatment of these very aggressive thyroid cancers. This type of cancer is one of the deadliest and most aggressive cancers, and with current limited treatment options, most patients have a grim prognosis of six months or less. “

Samer SROUR, MB CHB, Associate Professor of Stem Cell Transplantation and Cell Therapy

AIC100 is a third-generation auto-T cell therapy that binds to ICAM-1 on tumor cells to eliminate them. The car product expresses a protein called somatostatin receptor 2, allowing clinicians to monitor the effectiveness of therapy using special positron emission tomography (PET).

The multicenter study enrolled 24 adult patients with newly diagnosed or relapsed/refractory ATC and relapsed/refractory PTDC with measurable disease. Fifteen patients received AIC100 on December 12, 2024 after the data crash. Patients had an average of two prior lines of systemic therapy. The investigators began by evaluating three doses of AIC100. Patients received therapy intravenously at least 48 hours after three days of standard lymphodepletion.

After treatment with dose level 1, no responses were observed in four ATC patients at doses 2 and 3, the overall objective response rate was 50%. There was one patient in the dose -2 cohort with a partial response and one patient in the dose -3 cohort with a complete response; Both remained without evidence of progression up to five and seven months after treatment, respectively. In five patients with PDTC who received doses 2 and 3, the disease control rate was 60%.

No dose-limiting toxicities were observed at the initial planned three dose levels. Ten patients developed grade 1/2 cytokine release syndrome (CRS). At dose levels 1-3, no serious adverse events occurred and no patients developed ICANs, a neuropsychiatric disorder that can cause an adverse reaction to CAR T-cell therapy. Based on efficacy and safety results, researchers examined a fourth dose level at which two patients developed grade 3 pneumonitis.

Based on the observed safety and efficacy, the Level 3 dose was selected as the recommended dose for a future Phase II study.

“These results really bring hope that we may be working toward bringing a potentially effective new treatment option to patients with thyroid cancer,” Srour said. "While it is still early, complete remission and partial response provide a strong foundation for us and other researchers to improve outcomes and potentially induce durable remissions for this very aggressive disease."

The trial was supported by Affyimmune Therapeutics.

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