Ixekizumab continues to show benefit for nr-axSpA

Use of the monoclonal antibody ixekizumab led to improvements in symptoms, work productivity, and overall functioning and health in patients with nonradiographic axial spondyloarthritis (nr-axSpA), subgroup results of the phase III COAST-X trial have shown.

A total of 303 bDMARD*-naïve participants were randomized 1:1:1 to receive ixekizumab 80 mg Q2W or Q4W, or placebo, for 52 weeks. If disease activity persists by week 16, participants may switch to open-label ixekizumab Q2W or a tumour necrosis factor inhibitor.

Common symptoms

At week 16, compared with placebo, both ixekizumab regimens led to significant improvements in spinal pain (–2.59 vs –1.45; p≤0.001 [Q2W] and –2.35 vs –1.45; p<0.05 [Q4W]) and BASDAI** stiffness (–2.89  vs –1.44; p≤0.001 and –2.44 vs –1.44; p<0.05, respectively). The Q4W regimen also improved fatigue (–2.1 vs –1.4), while the Q2W regimen improved spinal pain at night (–2.79 vs –1.71; p<0.05 for both). [EULAR 2020, abstract FRI0286]

Although both ixekizumab regimens improved stiffness by week 52 (–3.48 vs –1.94; p≤0.001 [Q2W] and –3.15 vs –1.94; p<0.05 [Q4W]), the Q2W regimen fared better at this time given the additional improvements in spinal pain (–3.32 vs –2.29) and spinal pain at night (–3.58 vs –2.25; p<0.05 for both).

Compared with placebo, ixekizumab use also led to significant improvements in PtGA*** at week 16 (–2.64 vs –1.30; p≤0.001 [Q2W] and –2.32 vs –1.30; p<0.05 [Q4W]) and week 52 (–3.30 vs –1.81; p<0.05 [Q2W]).

Work productivity

Patients on ixekizumab Q4W had significantly greater improvement than those on placebo in terms of activity impairment and presenteeism (p<0.01 for both), as well as overall work impairment, at week 16 (p<0.05). Week 52 saw similar improvements in the same parameters with the same ixekizumab regimen (p<0.01 for all). [EULAR 2020, abstract THU0384]

The Q2W ixekizumab regimen also trumped placebo in terms of activity impairment at weeks 16 and 52 (p<0.01 for both).

Overall function, health

Week 16 saw significantly more ixekizumab vs placebo recipients achieving ASAS HI^# scores ≥3 (Q2W) and ≤5 (Q4W; p<0.05 for both). [EULAR 2020, abstract FRI0278]

From week 36–52, both ixekizumab regimens outshined placebo in terms of the percentage of participants achieving ASAS HI scores ≥3 (34 percent vs 19 percent [Q2W] and 33 percent vs 19 percent [Q4W]; p<0.05 for both) and ≤5 (35 percent vs 13 percent; p<0.001 [Q2W] and 27 percent vs 13 percent; p<0.05 [Q4W]).

“The smallest detectable change [in ASAS HI] was calculated at 3,” said the researchers. The achieved ASAS HI ≥3 scores were “clinically meaningful”, while the ASAS HI ≤5 scores signified “a good health state”, they noted.

Nr-axSpA greatly impairs health-related quality of life, including work productivity, of afflicted individuals. [Clin Exp Rheumatol 2016;34:975-983; Lancet 2018;392:2441-2451; Arthritis Rheumatol 2019;71:599-611] Collectively, the improvements seen with ixekizumab signify the achievement of good overall functioning and health status among adults with nr-axSpA, further boosting the previously reported therapeutic potential of the study drug. [Lancet 2020;395:53-64]