Patients with rheumatoid arthritis have increased oxidative stress, which the study's authors note may contribute to inflammation and elevated blood pressure. A randomized phase 2 clinical trial tested whether an oral compound designed to intercept specific products of that oxidative stress could make a measurable difference, and the results were largely negative, though the compound's safety profile was encouraging.
The compound, 2-hydroxybenzylamine acetate, known as 2-HOBA, works by scavenging reactive downstream products of oxidative stress, including a family of molecules called isolevuglandins, or IsoLGs. These isolevuglandins are particularly damaging because they covalently bind to proteins and alter their structure, potentially fueling inflammatory processes. Because 2-HOBA scavenges IsoLGs before they can attach to proteins, the pilot study evaluated its potential effects on disease activity and blood pressure in rheumatoid arthritis patients.
The trial was a single-center, randomized, double-blind, parallel-group phase 2 study. Thirty-two patients with rheumatoid arthritis were enrolled and randomized to receive either 750 mg of 2-HOBA or a matching placebo, taken orally three times daily for four weeks. The primary outcomes were safety, tolerability, and the change in cells carrying isolevuglandin-protein adducts. Exploratory outcomes included changes in disease activity and blood pressure, with linear mixed-effects models used to assess treatment effects of 2-HOBA compared with placebo.
The modified intention-to-treat population included 30 participants, 16 assigned to 2-HOBA and 14 to placebo. The headline finding on safety was positive: 2-HOBA was safe and well tolerated, with similar adverse event rates between the two groups.
On the primary mechanistic endpoint, however, the trial found no significant effect. Compared with placebo, 2-HOBA did not significantly alter the proportion of cells with isolevuglandin-protein adducts, with a treatment effect of 3.4 percent and a 95 percent confidence interval spanning from -4.0 to 10.9 percent, and a p-value of 0.35. Plasma isolevuglandin-lysine adducts likewise showed no significant change, with an estimated difference of -2.14 pg/mg protein and a 95 percent confidence interval of -5.01 to 0.73, and a p-value of 0.14.
The exploratory clinical outcomes told a similar story. No significant effects were observed on disease activity measured by DAS28-CRP or on blood pressure, with all p-values exceeding 0.05. The researchers did note that swollen and tender joint counts and systolic blood pressure showed small, non-significant improvements with 2-HOBA, hints that may guide future research but do not constitute evidence of benefit in this trial.
The authors conclude that 2-HOBA was safe and well tolerated in patients with rheumatoid arthritis, and that over the four-week treatment period no statistically significant changes were observed in cellular or plasma isolevuglandin-protein adducts or in the exploratory clinical outcomes. It is worth emphasizing the scope of these findings: this was a small pilot study of 30 participants treated for only four weeks at a single center, so it cannot rule out effects that might emerge with longer treatment, different dosing, or larger samples.
The trial was registered at ClinicalTrials.gov as NCT05274243 on March 1, 2022, and the results were published in Arthritis Research & Therapy as an open-access research article on October 21, 2026.
In this trial, 2-HOBA was safe and well tolerated in patients with rheumatoid arthritis, but no statistically significant changes were observed in cellular or plasma isolevuglandin-protein adducts or in the exploratory clinical outcomes over the four-week treatment period.
Subject of Research: A randomized phase 2 clinical trial testing the oxidative stress scavenger 2-HOBA in patients with rheumatoid arthritis
Article Title: 2-Hydroxybenzylamine acetate (2-HOBA) in rheumatoid arthritis: a randomized phase 2 clinical trial
Article References: Ramirez-Becerra, C., Kulapatana, P., Chen, S.-C., Phothisane, A., Posey, O., Chen, W., Harrison, D. G., Davies, S. S., Stein, C. M., & Ormseth, M. J. (2026). 2-Hydroxybenzylamine acetate (2-HOBA) in rheumatoid arthritis: a randomized phase 2 clinical trial. Arthritis Research & Therapy. https://doi.org/10.1186/s13075-026-03928-1
Image Credits: AI Generated
DOI: 10.1186/s13075-026-03928-1
Keywords: rheumatoid arthritis, 2-HOBA, oxidative stress, isolevuglandins, phase 2 trial, blood pressure, DAS28-CRP, clinical trial, inflammation, safety, Hydroxybenzylamine, acetate
News Source: Ophelia Keating. (October 29, 2026). Oxidative stress scavenger 2-HOBA proves safe but shows no significant benefit in rheumatoid arthritis trial. Scienmag.
