Enrollment Complete for Phase 2 Alzheimer Trial of Low-Dose Interleukin-2
The double-blind, placebo-controlled trial, which includes 2 dosing regimens of COYA 302, is expected to have topline data reported later this summer.
Fred Grossman, DO
According to a new announcement, enrollment for Coya Therapeutics’ phase 2, investigator-initiated, double-blind, placebo-controlled study assessing low-dose (LD) interleukin(IL)-2 treatment in patients with mild-to-moderate Alzheimer disease has been completed. The study, which features 38 individuals with the disease, is expected to have topline data reported in the summer of 2024.1
Funded by the Gates Foundation and the Alzheimer’s Association, the trial aims to evaluate the efficacy and safety of LD IL-2, otherwise known as COYA 302, at 2 different dosing regimens, in comparison with placebo. In the study, patients in the first cohort were randomized to receive LD IL-2 for 5 consecutive days every 4 weeks while the second cohort was randomized to LD IL-2 for 5 consecutive days every 2 weeks.
The trial, which primarily assesses safety, tolerability, and biological activity of LD IL-2, is comprised of a 21-week treatment period, followed by a 9-week follow-up. The study will also include other assessments of blood and cerebrospinal fluid biomarkers, neuroimaging, and changes in cognitive function across different patient populations. COYA 302, which is also being evaluated as a treatment for amyotrophic lateral sclerosis (ALS), is built of a dual immunomodulatory mechanism of action intended to enhance the anti-inflammatory function of regulatory T cells (Tregs) and suppress the inflammation produced by activated monocytes and marcophages.
"This is an important study that will help advance our expanding pipeline in dementia. We look forward to unblinding the data from this controlled study in Alzheimer Disease and releasing the top-line results this summer," Fred Grossman, DO, president and chief medical officer at Coya, said in a statement.1
In an open-label, proof-of-concept study featuring 8 patients with AD, treatment with COYA 302 resulted in mean percentage of Tregs to significantly increase from 4.55 (SD, 1.97) at baseline to 8.68 (SD, 2.99) at the end of treatment (P = .0004). From baseline to the conclusion of treatment, patients demonstrated significant increases in mean Treg suppressive function, from 46.61% (SD, 7.74) to 79.5% (SD, 20.55). The therapy was also considered well-tolerated as well, with mild injection-site reactions and mild leukopenia as the most commonly reported adverse events (AEs).
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Additional data from the small-scale trial revealed cognitive improvements with COYA 302 treatment relative to placebo, as assessed through the Mini Mental State Examination (P = .015). Consistent with the positive trend in MMSE score, mean scores in Alzheimer Disease Assessment Scale cognitive subscale and Clinical Dementia Rating-Sum of Boxes scales did not significantly change at the end of treatment, compared with pre-treatment baseline scores, indicating cognitive stabilization.
COYA 302 is comprised of proprietary LD IL-2 and CTLA-4 immunoglobulin and is being developed for subcutaneous administration for the treatment of patients with ALS, frontotemporal dementia, and Parkinson disease. In a first-of-its-kind, open-label study of patients with ALS, treatment with the dual-acting agent resulted in significant amelioration in disease progression over a 48-week period. Overall, the mean ALS Functional Rating Scale-Revised (ALSFRS-R) scores at week 24 (33.75 [±3.3]) and week 48 (32 [±7.8]) were not statistically different compared with values observed at baseline (33.5 [±5.9]).2
Treg suppressive function, expressed as percentage of inhibition of proinflammatory T cell proliferation, showed a statistically significant increase over the course of the treatment period and was significantly reduced at the end of the 8-week washout post-treatment period. Overall, Treg suppressive function at 24 weeks (79.9 [±9.6]) and 48 weeks (89.5 [±4.1]) were significantly higher compared with baseline (62.1 [±8.1]; P <.01). In contrast, Treg suppressive function was significantly decreased at the end of the 8-week washout period compared with week 48, or the end of treatment period (70.3 [±8.1] vs 89.5 [±4.1]; P <.05).
