Rocatinlimab Significantly Improves Clinical Signs and Symptoms of Moderate-to-Severe Atopic Dermatitis by Specifically Reducing OX40R+ T-Cell Population Without Signs of Immunosuppression
Emma Guttman-Yassky (New York, United States of America), Benjamin D. Ehst (Portland, OR, United States of America), H. Chih-Ho Hong (Surrey, Canada), Johannes S. Kern (Parkville, VIC, Australia), Nina Magnolo (Münster, Germany), Andrew E. Pink (London, United Kingdom), Pedro Herranz Pinto (Madrid, Spain), Jonathan Bernstein (Ohio City, United States of America), Andrea Wang (Thousand Oaks, CA, United States of America), Carolina Barragan (Thousand Oaks, United States of America), Ehsanollah Esfandiari (London, United Kingdom), Liat Schwartz-Sagi (Thousand Oaks, CA, United States of America), Kenji Kabashima ( Kyoto, Japan)
Background

In atopic dermatitis (AD) the OX40 receptor (OX40R) is upregulated, driving T-cell imbalance and disease chronicity. Rocatinlimab (ROCA; AMG 451/KHK4083), a novel T-cell rebalancing therapy, reduces pathogenic T cells by targeting OX40R. The phase 3 multicenter randomized double-blind ROCKET-Horizon trial (NCT05651711) evaluated ROCA monotherapy vs PBO in adults with moderate-to-severe AD (msAD) and inadequate response to topicals. We report evidence of ROCA clinical efficacy, safety and effect on T cells.

Method

Adults ≥18yrs were randomized 3:1 to SC ROCA 300mg or PBO Q4W for 24 wks (+wk2 loading dose). Co-primary endpoints (wk24): ≥75% improvement in Eczema Area and Severity Index (EASI-75); Validated Investigator Global Assessment scale for AD (vIGA-A™) 0 (clear) or 1 (almost clear) with ≥2-point reduction from BL. Rescue therapy (RT) was permitted from D1. Primary analysis considered RT users/missing data as nonresponders; a prespecified sensitivity analysis reported RT users as observed (AO). Safety analyses included pts receiving ≥1 study drug dose; outcomes included TEAEs, lab value changes and biomarkers.

Results

Fig1 shows the study disposition. Co-primary endpoints were met (EASI-75 [ROCA vs PBO], 32.8% vs 13.7%; vIGA-AD 0/1, 19.3% vs 6.6%; both P<0.001). AO analysis showed even greater improvements for ROCA vs PBO (EASI-75, 46.6% vs 15.8%; vIGA-AD 0/1, 24.1% vs 6.6%; both P<0.001). RT use was lower for ROCA vs PBO (33.5% vs 41.5%). Most common TEAEs (≥4% any tx grp) are noted (Table1). Pyrexia and chills were mild to moderate, predominantly reported only after first ROCA dose and resolved within 48hrs. Infection incidence was similar for ROCA vs PBO (36.4% vs 31.1%), few events required systemic antibiotics (ROCA vs PBO, 2.9% vs 5.0%), none led to study discontinuation. No opportunistic infections were reported in either grp. There were no deaths. No significant clinical changes in overall WBC count from BL, including T-cell numbers, were observed; wk24 counts for both grps remained within normal reference range (Table1). OX40R+ T cells were reduced with ROCA while sparing OX40R- cells.

Conclusion

ROCA significantly improved clinical signs and symptoms of msAD (primary and AO analyses), reducing OX40R+ T cells while maintaining the overall T-cell population with no meaningful impact on infections. These data indicate clinical efficacy without signs of immunosuppression and support ROCA as a novel monotherapy option.