Reviews/Psoriasis Psoriatic Arthritis/Secukinumab ASAS20 in axial psoriatic arthritis
Psa Axl · PSA-AXL-01 · v2
Borderline: within 4 points of the Established/Likely boundary, so a re-grade could land either side.
One large, high-quality trial tested whether secukinumab helps patients with psoriatic arthritis who also have spine involvement. In that trial, far more patients on secukinumab reached the main pre-set response target than on placebo, and the difference was very unlikely to be chance [1]. The improvement was still there a year later [3][4]. The main caveat is that every piece of evidence here comes from that one trial, reported in several different formats, rather than from separate studies that confirm each other. The panel judged the claim well supported because the trial matches the claim almost exactly, but held back from the very top because a single trial stands alone.
The phase 3 double-blind, placebo-controlled MAXIMISE trial reported that secukinumab 300 mg and 150 mg improved ASAS20 response versus placebo at week 12 (63% and 66% vs 31%, OR 3.8 and 4.4, p<0.0001) [1]. A congress analysis of the same trial labels the primary and key secondary endpoints as met and gives ASAS20 rates of 63.1% and 66.3% versus 31.3% [2]. Two week-52 reports show the response sustained and increased through 52 weeks [3][4], and an MRI sub-study of the same cohort notes an efficacy trend on ASAS20 [5]. The enrolled population — PsA with axial manifestations and inadequate response to NSAIDs — matches the claim's wording [1][2]. The contested point: The evidence does not divide on whether the endpoint was met; every corpus source agrees it was. The only point of tension is evidential independence: all five included sources [1]-[5] are the single MAXIMISE trial, so consistency is high but there is no second study to confirm the result.
All 7 papers behind this claim with their DOIs and what each does to it, the panel’s arbitration, the evidence gap map and the open research questions. Free, and sent to your inbox.
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One reviewer's only job is to attack the finding. The challenges below were weighed before the grade was set.
All included sources [1]-[5] are the single MAXIMISE trial; there is no independent replication of the ASAS20 result, so the claim rests on one RCT reported five ways.
Sources [2], [3] and [4] are congress abstracts of the same dataset, not independent peer-reviewed reports, so risk-of-bias detail (missing-data handling, week-12 imputation) cannot be verified from the corpus; only [1] provides peer-reviewed confirmation of the primary result.
Where it remains uncertain. Every included source [1]-[5] is the same MAXIMISE trial, and three of them [2][3][4] are congress abstracts, so there is no independent replication in the corpus.
Aleatory
Roughly a third to 37% of secukinumab-treated patients did not reach ASAS20 at week 12 [1], reflecting inherent patient-to-patient variation in response.
The load-bearing papers from a corpus of 7, each classified by what it does to the claim. Every DOI is taken from the corpus the claim was graded on.
Pivotal peer-reviewed RCT result: ASAS20 primary endpoint met with strong statistics.
“Secukinumab 300 mg and 150 mg significantly improved ASAS20 response versus placebo at week 12 (63% and 66% vs 31% placebo). The OR comparing secukinumab 300 mg and 150 mg versus placebo was 3.8 and 4.4 (p<0.0001).”
Panel auditInternal validity: high · scope of inference: PsA patients with axial manifestations and inadequate response to NSAIDs, week 12 ASAS20.Key limitations: total sample size not stated in abstract · week 12 timepoint only in this quote
Explicitly states the primary endpoint was met (same trial as [1]).
“Primary and key secondary endpoints were met; ASAS20 response rates at Wk 12 were 63.1% (SEC 300 mg; P<0.0001) and 66.3% (150 mg; P<0.0001) vs 31.3% (PBO).”
Panel auditInternal validity: high · scope of inference: PsA patients with axial manifestations and inadequate NSAID response, week 12 ASAS20.Key limitations: sample size not stated in abstract · conference-abstract level reporting
Confirms week-12 ASAS20 magnitude and reports durability to 52 weeks.
“ASAS20/40 responses at Week 12 were 62.9%/43.6% (secukinumab 300 mg) and 66.3%/39.5% (secukinumab 150 mg) versus 31.2%/12.2% (placebo).”
Panel auditInternal validity: high · scope of inference: PsA patients with axial manifestations, ASAS responses at week 12 through 52 weeks.Key limitations: no p value or significance test in abstract · sample size not stated
The abstract reports only a trend by MRI subgroup, not a placebo-referenced ASAS20 endpoint result, so it cannot confirm or refute the primary endpoint being met.
Panel auditInternal validity: not assessable from abstract · scope of inference: MRI phenotype subgroups within the MAXIMISE cohort and their association with efficacy outcomes.Key limitations: no primary endpoint result reported · trend only, no statistics · subgroup analysis
4 of 7 papers shown. The full review lists all of them, with the panel’s arbitration →
Claims are graded at each quarterly release, and re-graded between releases only when a pivotal trial lands. Every change is a new version of the claim.
A direct, on-population phase 3 RCT robustly met the pre-specified ASAS20 primary endpoint, but single-trial evidence caps confidence short of the maximum.
Release 2026-q4 re-graded every claim from its corpus under protocol v0.19. An earlier release's grade is shown for the record; it came from an earlier protocol and is not a movement.
Assumptions that carry weight but are not themselves established.
The panel records the gap that would most move the claim, and the study that would close it.
No independent replication trial. The claim rests entirely on MAXIMISE; a second, separately-run RCT would confirm the ASAS20 result is not trial-specific. The panel rates this the highest-importance open gap for the claim, and names the study design that would close it: An independent phase 3 randomised placebo-controlled trial of secukinumab in axial PsA powered on ASAS20.
Open question: Does secukinumab meet ASAS20 in axial PsA when tested in a trial independent of MAXIMISE? Why it is still open: Every source in the corpus [1]-[5] is the single MAXIMISE trial, with no external confirmation.
Priors is a sceptical first reader, not peer review, and not medical advice.
Release 2026-q4 · graded 18 Sep 2026 · protocol v0.19