This single-center, phase I, randomized, double-blind, placebo-controlled trial assessed the safety of single ascending doses (SAD) of olamkicept in healthy Japanese adult men. The study randomized 24 participants to receive a single intravenous infusion of olamkicept at 1200 mg, 1800 mg, or 2400 mg, or placebo. Safety evaluations included monitoring of treatment-emergent adverse events (TEAEs), vital signs, 12-lead electrocardiograms (ECG), clinical chemistry, hematology, hemostasis, and urinalysis.
Across the cohort, four TEAEs were reported. All TEAEs were classified as mild and resolved without any medical intervention. No adverse drug reactions were identified. The investigators observed no treatment- or dose-related trends in TEAEs, vital signs, ECG parameters, clinical chemistry, hematology, hemostasis markers, or urinalysis findings. These safety results support a favorable tolerability profile for single doses of olamkicept up to 2400 mg in this healthy Japanese population.
Pharmacokinetic (PK) parameters were prespecified secondary outcomes in the trial. A single IV infusion of olamkicept achieved measurable serum concentrations for up to 28 days following dosing. Systemic exposure increased with dose and was described as dose proportional across the tested range (1200–2400 mg). Graphical PK data presented in the source showed individual and mean serum concentration–time profiles and plots of Cmax and AUCinf versus dose that supported proportionality.
These PK findings indicate sustained measurable exposure after a single infusion and a predictable relationship between dose and systemic exposure in healthy Japanese men. The data are consistent with prior SAD and multiple ascending dose (MAD) assessments reported previously in other populations, which had evaluated SAD up to 750 mg and MAD up to 600 mg daily.
The trial was conducted as a within-group randomized, double-blind study at a single center in Japan. Twenty-four healthy adult men were enrolled and randomized to receive one of three ascending single doses of olamkicept (1200, 1800, 2400 mg) or placebo. The study population and single-dose design allowed assessment of acute safety and standard PK endpoints after IV administration.
Olamkicept is described in the source as a first-in-class, fully human fusion protein that selectively inhibits trans interleukin-6 signaling, a pathway implicated in inflammatory conditions such as inflammatory bowel disease. The trial was registered at ClinicalTrials.gov (identifier NCT06515834).
In this Japanese cohort, immunogenicity was not assessed. The source explicitly states that anti-drug antibody testing or other immunogenicity endpoints were not performed for these participants. This omission is a limitation when interpreting longer-term tolerability and PK variability, as immunogenic responses can affect both safety and pharmacokinetics in repeated-dose settings.
Additional limitations inherent to the reported study include the single-dose design and the healthy male-only participant population, which may limit direct extrapolation to patients with target disease states or to females. The sample size was small, as typical for phase I SAD studies, and the results are therefore descriptive rather than powered for inference on rare adverse events.
The published record discloses that several authors (K.B., M.F., L.-E.K., S.M., A.R., and N.Y.) are employees of Ferring Pharmaceuticals. One author (P.P.) is employed by Ferring Pharmaceuticals, serves on a board of directors at PharmaBiome, and holds stocks in Takeda Pharmaceutical Co. Ltd. The lead author (R.H.) declared no conflicts of interest. The source indicates publication in Clinical and Translational Science and provides DOI and PubMed identifiers for reference.
Single IV doses of olamkicept up to 2400 mg were well tolerated in healthy Japanese men in this randomized, double-blind, placebo-controlled phase I trial. There were four mild, self-limited TEAEs and no adverse drug reactions reported. Pharmacokinetic analysis showed measurable serum concentrations for up to 28 days after dosing and dose-proportional systemic exposure across the evaluated range.
These results extend prior SAD and MAD findings in other populations and support continued clinical development of olamkicept. Key unanswered items in this cohort include immunogenicity after single or repeated dosing and tolerability in patient populations; these were not assessed or reported in the source and would need to be addressed in subsequent trials. The trial is registered as NCT06515834 for reference and follow-up of study details and full datasets.