Coya Therapeutics, Inc. announced completion of enrollment in a randomized, double-blind, placebo-controlled phase 2 study of LD IL-2 in patients with mild-to-moderate AD. The study is being conducted by Drs. Stanley Appel and Alireza Faridar at the Houston Methodist Hospital.

A total of 38 patients were randomly assigned to receive subcutaneous LD IL-2 at two different dosing regimens, or matching placebo, over 21 weeks. The first patient cohort was randomized to receive LD IL-2 for 5 consecutive days every 4 weeks and the second cohort was randomized to receive LD IL-2 for 5 consecutive days every 2 weeks. This phase 2 well-controlled study will evaluate the safety and tolerability, biological activity, blood and cerebrospinal fluid biomarkers, neuroimaging, and changes in cognitive function of LD IL-2 compared to placebo at pre-specified timepoints over the course of the 21-week treatment period and at 9 weeks after the last dose of study treatment.

Topline results of the study are anticipated to be reported in Summer 2024. The study is funded by the Gates Foundation and the Alzheimer?s Association. Coya previously reported that the treatment with LD IL-2 significantly expanded Treg population and function in an open-label proof-of concept study in 8 patients with AD.

At baseline, the mean (SD) percentage of Tregs was 4.55 (1.97) and was almost double at the end of the treatment [8.68 (2.99), p=0.0004]. Mean (SD) Treg suppressive function was 46.61% (7.74) at baseline, and significantly increased to 79.5 % (20.55) at the end of treatment (p=0.003). In addition, evaluation of cognitive function showed that administration of LD IL-2 resulted in a statistically significant improvement in mean MMSE scores during the treatment phase, compared to mean MMSE score at baseline (p=0.015).

Consistent with the positive trend in MMSE score, mean scores in ADAS-Cog and CDR-SB scales did not significantly change at the end of treatment with LD IL-2, compared to pre-treatment baseline scores, indicating no cognitive decline as measured by these validated instruments. Overall, administration of LD IL-2 appeared to be well tolerated in the 8 patients in the open-label, proof-of concept study. The most common adverse events were mild injection-site reactions and mild leukopenia.

No serious adverse events were reported, and no patient discontinued the study.