- Weidinger S. Efficacy and safety of amlitelimab (an anti-OX40 ligand antibody) in patients with moderate-to-severe atopic dermatitis: 24-week results from a Phase 2b trial (STREAM-AD). D3T01.3G, EADV Congress 2023, 11–14 October, Berlin, Germany.
STREAM-AD (NCT05131477) is a phase 2b monotherapy trial designed to test 5 different dosages of the OX40 ligand inhibitor amlitelimab against placebo in adults with moderate-to-severe AD, expressed by a baseline EASI of ≥16, an Investigator’s Global Assessment (IGA) of 3 or 4, and at least 10% of affected body surface area (BSA)1. Per design, 390 participants were randomised to a 4-weekly treatment with placebo or the study drug in 4 groups (250 mg + loading dose of 500 mg, 250 mg, 125 mg, or 62.5 mg). The primary endpoint was the proportion of EASI change at week 16. Follow-up of 6 more weeks completed part 1 of STREAM-AD.
“Overall, this was a typical moderate-to-severe AD population,” Prof. Stephan Weidinger (University Hospital Schleswig-Holstein, Germany) commented on the baseline characteristics. The mean age was 37.8 years, 43.8% were women, and the mean duration of AD was 22.3 years. Mean disease measures were EASI 28.9, IGA 3.3, and BSA involved 46.2%.
The study met its primary endpoint at week 16, with statistically significant superior EASI results that equalled least mean square changes between -61.5% (250 mg plus loading dose; P<0.0001) and -51.6% (125 mg; P=0.0002) compared with 29.4% in the placebo arm. On the highest dose, for example, EASI reductions continued up to week 24 with -64.4% or -73.1%, depending on the statistical approach to categorising cases of rescue medication.
Among the secondary endpoints were achievement of IGA 0/1, EASI75, and ≥4-point reduction on the Peak Pruritus Numerical Rating Scale (PP-NRS). Apart from IGA 0/1 on 250 mg without a loading dose, all groups on amlitelimab were significantly superior over placebo in these as well.
Up to week 24, treatment-emergent adverse events occurred in 67.4% (amlitelimab) and 60.3% (placebo) of the participants, with rates of treatment discontinuation at 4.5% and 6.4%, respectively. Overall, the agent was deemed well-tolerated.
The results of the second part of STREAM-AD, which includes a withdrawal/extension design for the 24-week responders and a safety follow-up until week 68, are eagerly awaited.