Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2025 Sep 16:16:1647816.
doi: 10.3389/fphar.2025.1647816. eCollection 2025.

Safety, tolerability, pharmacokinetics, immunogenicity and pharmacodynamics of 9MW1911, an anti-ST2 monoclonal antibody: results from a first-in-human phase 1 study

Affiliations

Safety, tolerability, pharmacokinetics, immunogenicity and pharmacodynamics of 9MW1911, an anti-ST2 monoclonal antibody: results from a first-in-human phase 1 study

Qian Zhao et al. Front Pharmacol. .

Abstract

Background: 9MW1911 is a high-affinity human IgG4 monoclonal antibody targeting ST2, the human IL-33 receptor. It may have anti-inflammatory effects by blocking the IL-33/ST2 pathway. This first-in-human trial (NCT05803902) aimed to evaluate the safety, tolerability, pharmacokinetics, immunogenicity and pharmacodynamics of 9MW1911 in healthy participants.

Methods: This phase I, randomized, double-blind, placebo-controlled study enrolled 48 healthy adults. After a screening period of up to 28 days, they received a single ascending intravenous dose (ranging from 25 to 1200 mg) of 9MW1911 (n = 6 per dose) or matched placebo (n = 2 per dose). Parameters of safety, pharmacokinetics, immunogenicity and pharmacodynamics were evaluated, with follow-up visits until day 113 post-dosing.

Results: 9MW1911 was safe and well-tolerated across various doses. Most AEs were of mild to moderate, resolved without treatments. No dose-related AEs were observed, and the only serious AE (fetal malformation) was deemed unrelated to the study drug. No deaths or discontinuations due to AEs occurred. 9MW1911 ranging from 25 mg to 1,200 mg demonstrated a non-linear increase in exposure, while a linear PK profile was observed in the dose range from 100 mg to 1200 mg. No anti-drug antibodies were detected in any participants. Total sST2 in serum increased and stabilized at higher dose levels, demonstrating sustained target binding.

Conclusion: The study demonstrates that 9MW1911 was safe and well-tolerated in healthy participants. As 9MW1911 concentrations increased,the sustained elevation of sST2 in the higher dose levels (100mg-1200 mg) suggested that the target-mediated drug disposition (TMDD) elimination became saturated, leading to the observed linear PK profile. These data support the continued development of 9MW1911 for the therapeutic use in the relevant disease.

Keywords: 9MW1911; ST2; first-in-human trial; pharmacokinetics; safety.

PubMed Disclaimer

Conflict of interest statement

Author(s) DY, JF, ZH and YG were employed by Mabwell (Shanghai) Bioscience Co., Ltd. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The authors declare that this study received funding from Mabwell (Shanghai) Bioscience Co., Ltd. The funder had the following involvement in the study: study design, conduct, data collection, management, analysis, and interpretation.

Figures

FIGURE 1
FIGURE 1
Study design.
FIGURE 2
FIGURE 2
Mean (standard deviation) serum 9MW1911 concentration-time curves following a single intravenous dose of 25 mg, 50 mg, 100 mg, 300 mg, 600 mg, and 1200 mg 9MW1911. (A) Linear scale; (B) Semi-log scale.
FIGURE 3
FIGURE 3
Target binding of 9MW1911 assessed by total sST2 in serum. Data are shown as mean (standard deviation). sST2 = soluble ST2.

References

    1. Akdis C. A., Arkwright P. D., Bruggen M. C., Busse W., Gadina M., Guttman-Yassky E., et al. (2020). Type 2 immunity in the skin and lungs. Allergy 75 (7), 1582–1605. 10.1111/all.14318 - DOI - PubMed
    1. Bergers G., Reikerstorfer A., Braselmann S., Graninger P., Busslinger M. (1994). Alternative promoter usage of the Fos-responsive gene Fit-1 generates mRNA isoforms coding for either secreted or membrane-bound proteins related to the IL-1 receptor. EMBO J. 13 (5), 1176–1188. 10.1002/j.1460-2075.1994.tb06367.x - DOI - PMC - PubMed
    1. Cayrol C. (2021). IL-33, an alarmin of the IL-1 family involved in allergic and non allergic inflammation: focus on the mechanisms of regulation of its activity. Cells 11 (1), 107. 10.3390/cells11010107 - DOI - PMC - PubMed
    1. Levy G. (1994). Pharmacologic target-mediated drug disposition. Clin. Pharmacol. Ther. 56 (3), 248–252. 10.1038/clpt.1994.134 - DOI - PubMed
    1. Liew F. Y., Girard J. P., Turnquist H. R. (2016). Interleukin-33 in health and disease. Nat. Rev. Immunol. 16 (11), 676–689. 10.1038/nri.2016.95 - DOI - PubMed

LinkOut - more resources