In patients with psoriatic arthritis
(PsA), new evidence suggests selection of biologic disease-modifying antirheumatic drugs
(bDMARDs) might be individualised by T-helper cell phenotype to
improve disease control, according
to the results of a study presented
at the Congress.
“Our findings suggest a potential
for precision medicine in patients
with psoriatic arthritis,” reported Dr.
Ippei Miyagawa of the University
of Occupational and Environmental
Health in Kitakyushu, Japan.
In this study, 26 patients were
divided into four lymphocyte
phenotypes based on the peripheral blood analysis. These were
activated Th1 cell–predominant
type (Th1 predominant), a CX-
CR3-CCR6+CD38+HLA-DR+ activated Th17 cell–predominant type
(Th17 predominant), a Th1/Th17-
high type–predominant type (Th1/
Th17 high), and a Th1/Th17-low–
predominant type (Th1/Th17 low).
These phenotypes were employed to individualise therapy with
the currently available targeted
bDMARDs. Patients with a Th1-
predominant phenotype received
ustekinumab, which blocks the p40
subunit of interleukin (IL)- 12 and
IL- 23. Patients with a Th17-predom-
inant phenotype received secukinumab, which targets IL- 17. Patients
with the Th1/Th17-high phenotype
received either secukinumab or a
tumour necrosis factor inhibitor. Patients with the Th1/Th17-low phenotype received a TNF inhibitor.
The 26 patients whose bDMARD
therapy was individualised were
compared with 38 PsA patients
who received bDMARDs selected
according to EULAR recommendations. The groups were similar for
In both groups, there were sig-
nificant decreases from baseline
in essentially all clinical measures,
including the Simplified Disease
Activity Index, the Psoriasis Area
and Severity Index, and the Pa-
tient Global Health Assessment.
However, several disease markers
suggested greater disease control
Activity Score in 28 joints using
erythrocyte sedimentation rate
(DAS28-ESR) at 6 months was 0.76
in the Th17-predominant group ver-
sus 1. 32 in those on an unselected
bDMARD therapy (P = .008).
As a proportion of lymphocytes,
Th1-predominant cells greater than
1.2% and Th17-predominant cells
greater than 1.5% appeared to be
sensitive cutoffs for predicting response to ustekinumab and secukinumab, respectively, according to
data presented by Dr. Miyagawa.
Although the results in this small
series of patients are considered
preliminary, Dr. Miyagawa said,
“We think that this research is the
first step toward the future use of
precision medicine in PsA.”
Larger studies are needed to ver-
ify that lymphocyte phenotyping is
an effective and reproducible strat-
egy for individualising selection
of bDMARDs, but Dr. Miyagawa
acknowledged other practical bar-
riers to routine clinical application
of this strategy. In particular, he
called flow cytometry, which was
employed in this study to pheno-
type lymphocyte expression, “com-
plicated” for routine clinical use.
However, this study strongly sug-
gests that lymphocyte expression
is a predictor of response to the
different bDMARDs now available
for treatment of PsA.
“The bDMARDs effective in PsA
have different targets and may not
offer the same degree of efficacy
in all patients. Our study suggests
an approach to optimal drug selection,” he said.
The study was not industry funded. Dr. Miyagawa reported no relevant financial disclosures.
Dr. Ippei Miyagawa
Biologic efficacy differs in psoriatic arthritis
by lymphocyte phenotype
BY TED BOSWORTH
“The bDMARDs effective
in PsA have different
targets an may not offer
the same degree of
efficacy in all patients.
Our study suggests an
approach to optimal drug