Patient Satisfaction Using Guselkumab Self-administered Using the One-Press Device for Treatment of Moderate-to-Severe Psoriasis: Results from a National, Prospective, Real-World Study in Portugal (CERES Study)

Abstract

Introduction

Guselkumab, a selective p19 subunit-targeted IL-23 inhibitor, has shown high efficacy and a favorable safety profile in clinical trials of moderate-to-severe plaque psoriasis (PsO). However, real-world data on patient satisfaction with the guselkumab One-Press device, particularly in Portuguese clinical practice, are limited.

Methods

This real-world, prospective, multicenter, nationwide study evaluated patient satisfaction with self-administration of guselkumab using the One-Press device over 52 weeks in adults with moderate-to-severe plaque PsO. A total of 101 patients from 10 dermatology centers were enrolled between September 2022 and November 2023. Patient satisfaction was assessed using the Self-Injection Assessment Questionnaire (SIAQ) at baseline and week 20. Using the SIAQ, patients rated the One-Press device’s acceptability across six domains predose and postdose (feeling about injections, self-confidence, and satisfaction with self-injection; postdose only: self-image, pain and skin reactions during or after the injection, and ease of self-injection device use). Quality of life (Dermatology Life Quality Index [DLQI]), clinical effectiveness (Investigator Global Assessment [IGA]), and safety were evaluated through week 52.

Results

Mean SIAQ PRE Module score increased significantly from 6.9 ± 1.8 at baseline to 8.3 ± 1.5 at week 20 (p < 0.001), indicating improved self-injection experience. Injection-related anxiety decreased from 63.4% to 48.9%. Mean DLQI score improved from 8.5 ± 6.9 at baseline to 1.5 ± 2.8 at week 20 and 1.1 ± 3.0 at week 52; 70.8% of patients achieved DLQI 0/1 by week 52. Despite nearly 90% having prior biologic or systemic therapy exposure, IGA 0/1 (“clear” or “almost clear”) was achieved by 86.3% of patients at week 20 and 91.0% at week 52. A total of 198 adverse events (AEs) were reported in 62.4% of patients and were mainly mild, localized injection-site reactions. One serious AE was considered related to guselkumab.

Conclusions

In routine clinical practice in Portugal, guselkumab self-administered using the One-Press device demonstrated high patient satisfaction, substantial quality-of-life improvement, robust clinical effectiveness, and a favorable safety profile. These real-world findings support the usability and benefit-risk profile of self-administered guselkumab for patients with moderate-to-severe plaque PsO.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13555-026-01670-9.

Key Summary Points

Why carry out this study?

Moderate-to-severe plaque psoriasis (PsO) substantially impairs quality of life, and despite the proven efficacy of biologics such as guselkumab, real-world data on patient satisfaction with the One-Press device are limited.

Understanding the patient experience with self-administration devices is essential to optimize adherence, satisfaction, and treatment outcomes in routine PsO management.

This national, prospective, real-world study evaluated patient satisfaction, quality of life, clinical effectiveness, and safety of guselkumab self-administered using the One-Press device over 52 weeks in adults with moderate-to-severe PsO.

What was learned from the study?

Patient satisfaction improved significantly, with mean PRE Module score improving from 6.9 ± 1.8 at baseline to 8.3 ± 1.5 at week 20 (p < 0.001) and reduced injection-related anxiety (63.4–48.9% of patients).

Clinical and quality-of-life outcomes were robust, with 91.0% of patients achieving Investigator Global Assessment 0/1 (clear/almost clear) and 82.0% reaching Dermatology Life Quality Index 0/1 by week 52; most adverse events were mild and localized.

Guselkumab self-administered using the One-Press device was associated with high satisfaction, substantial improvements in disease control and quality of life, and a favorable safety profile, confirming its usability and benefit–risk balance in routine clinical use in Portugal.

Introduction

Psoriasis (PsO) is a chronic, immune-mediated inflammatory disease that affects around 2–4% of people in Western countries [1, 2]. In Portugal, the prevalence of psoriasis has been estimated at 4.4%, with significant gaps in diagnosis and management identified [3]. The most common form, chronic plaque PsO, is present in 80–90% of patients and usually appears as erythematous, scaly plaques on the scalp, trunk, buttocks, and the extensor surfaces of the limbs [2, 4]. PsO typically follows a relapsing–remitting course [5], affects men and women equally, and most often begins either in early adulthood or later in midlife. More than a disorder limited to the skin, PsO is increasingly recognized as a systemic condition, associated with comorbidities such as psoriatic arthritis, cardiovascular disease, inflammatory bowel disease, and psychiatric disorders [4–6].

Although plaque psoriasis is not life-threatening in the majority of cases, it has a profound impact on health-related quality of life. Patients frequently report stigma, emotional distress, and higher rates of depression and anxiety compared with the general population [5, 7, 8]. Known risk factors include family history, smoking, obesity, alcohol use, and psychological stress [1].

Ideally, treatment should be tailored to the individual, considering disease severity, comorbidities, and patient preferences [5, 8]. Over the past two decades, biologic therapies have transformed care for moderate-to-severe PsO by targeting key immune pathways. These include tumor necrosis factor (TNF), interleukin (IL)-17, and IL-12/23 or IL-23 inhibitors [9, 10]. Guselkumab, the first selective p19 subunit-targeted anti-IL-23 approved in Europe for adults with moderate-to-severe plaque PsO, has consistently shown high efficacy and a favorable safety profile in phase III trials, with over 80% of patients achieving clear or almost clear skin on the basis of the Investigator’s Global Assessment (IGA) measure at week 16 [11–14]. Administered by subcutaneous injection, guselkumab is available for self-administration using the One-Press device, which improves usability and has been associated with good tolerability and patient satisfaction [11, 12].

In PsO care, the use of patient-reported outcomes (PROs) has become increasingly important, as they capture patients’ perspectives on symptoms, treatment satisfaction, and quality of life—factors that cannot be assessed using physicians’ assessments [15–17]. While both randomized controlled trials and real-world studies have confirmed the efficacy and safety of guselkumab [18–22], evidence derived from PROs in daily clinical practice, particularly in Portugal, remains limited.

This real-world, prospective, multicenter, nationwide study aimed to evaluate patient satisfaction with self-administration of guselkumab using the One-Press device over 52 weeks in routine clinical practice in Portugal. Secondary objectives include assessment of quality of life (Dermatology Life Quality Index—DLQI), clinical effectiveness (IGA response), and safety.

Methods

Study Design and Patients

The CERES study was a prospective, multicenter, noninterventional study conducted across 12 Portuguese sites (Unidade Local de Saúde (ULS) Alto Ave, CUF Descobertas, ULS São José, ULS Santa Maria, ULS Região de Leiria, ULS Lisboa Ocidental, ULS Santo António, ULS Almada Seixal, ULS São João, and Hospital de Loulé). Enrollment took place from September 2022 to November 2023. Eligible patients were adults (> 18 years) diagnosed with moderate-to-severe plaque PsO who initiated or reinitiated guselkumab treatment according to routine clinical practice, in accordance with the approved dosing regimen outlined in the Summary of Product Characteristics (SmPC), 100 mg by subcutaneous injection at weeks 0 and 4, followed by a maintenance dose every 8 weeks (q8w). Treatment decisions were independent of study participation, and only routinely collected clinical data and approved patient-reported outcomes (PROs) were recorded. All adverse events (AEs) and special situations were collected from the first administration of guselkumab through 75 days after the last dose, irrespective of seriousness or causality.

The study was conducted in accordance with the Declaration of Helsinki and Good Clinical Practice (GCP) principles, with approval from the Independent Ethics Committee at each site. Enrollment of consecutive eligible patients presenting for routine visits at each site was recommended to minimize bias. All patients provided written informed consent. Reporting followed STROBE (Strengthening the Reporting of Observational Studies in Epidemiology) guidelines [23].

Study End Points

The primary end point was patient satisfaction with the guselkumab One-Press device based on change in SIAQ score at week 20 compared with baseline, with baseline defined as completion of the SIAQ PRE–self-injection module before the first guselkumab injection. Secondary end points included: patient satisfaction and expectations before the first injection (SIAQ Pre–self-injection) between biologic-naive patients and those with previous experience using biologic therapies; other SIAQ domains after the first injection and at week 20 follow-up; change in quality of life (DLQI score) at weeks 20 and 52 compared with baseline; and effectiveness based on change in IGA score at weeks 20 and 52 compared with baseline. This was an exploratory study; therefore, no formal hypotheses were prespecified. All patient-reported and clinician-reported outcome measures were used in compliance with applicable copyright and licensing requirements.

Statistical Analysis

The Full Analysis Set (FAS), defined as all patients meeting inclusion criteria, was used for primary, secondary, and safety analyses. Continuous variables were summarized using descriptive statistics (n, mean, standard deviation, median, minimum, and maximum), while categorical variables were presented as frequencies and percentages (total and valid). The primary end point was analyzed using absolute and relative frequencies with 95% confidence intervals. Comparisons of SIAQ scores before and after injection were performed using the McNemar test. Effectiveness was assessed by IGA (score 0/1 versus > 2) and quality of life by DLQI (score 0/1 versus > 2) at baseline, week 20, and week 52. Safety analyses included MedDRA coding of AEs and were summarized by frequency, with subgroup analyses restricted to groups with at least 15 patients (e.g., biologic-naive versus previously treated). Statistical tests used the McNemar test for categorical paired data and either the paired t-test or the Wilcoxon signed-rank test for continuous paired data, based on the Shapiro–Wilk normality test. All analyses used a two-sided significance level of 0.05. No imputation was performed; DLQI scores were calculated if < 1 item was missing. Analyses were conducted using R v4.3.1.

Results

Study Population and Baseline Characteristics

A total of 101 patients were enrolled, with 89 (88.1%) patients completing the study. Baseline demographic and clinical characteristics of the overall patient population are summarized in Table 1. The mean (± standard deviation, SD) age of patients was 49.6 ± 14.2 years, and 62.4% of patients were male. The mean (± SD) Body Mass Index (BMI) was 27.7 ± 5.9 kg/m². At least 79 patients (78.2%) had one or more documented comorbidity, and 29.7% of patients had three or more registered comorbidities. The most frequently reported comorbid conditions were hypertension (44.3%) and dyslipidemia (41.8%). At baseline, 59.4% of patients (n = 60) reported the use of at least one concomitant medication, while 40.6% (n = 41) had no available data (Table 1). Baseline PsO-related characteristics are summarized in Table 1. The mean (± SD) age at diagnosis was 35.3 ± 14.1 years, and the mean time since diagnosis was 204.5 ± 197.4 months. Notably, most patients did not report a diagnosis date (n = 83).

Table 1.

Baseline patient characteristics (n = 101)

Baseline demographic and clinical characteristics	Overall (n = 101) n (%)
Mean age, years (SD)	49.6 (14.2)
Male, n, (%)	63 (62.4%)
Female, n, (%)	38 (37.6%)
Mean body mass index, kg/m2 (SD)a	27.7 (5.9)
Comorbidities
Patients with registered comorbidities, n, (%)	79 (78.2%)
Not available, n, (%)	22 (21.8%)
Number of comorbidities per patient, n, (%)
1	25 (24.8%)
2	24 (23.8%)
> 3	30 (29.7%)
Comorbidities present in > four patients, n, (%)b
Hypertension	35 (44.3%)
Dyslipidemia	33 (41.8%)
Diabetes mellitus	15 (19.0%)
Anxiety/depression	12 (15.2%)
Psoriatic arthritis (PsA)	12 (15.2%)
Chronic obstructive pulmonary disease	6 (7.6%)
Cardiopathy and cardiac disorders	10 (11%)
Other	60 (75.9%)
Metabolism and nutrition disorders	19 (18.8%)
Infections and infestations	16 (15.8%)
Musculoskeletal and connective tissue disorders	13 (12.9%)
Hepatobiliary disorders	9 (8.9%)
Gastrointestinal disorders	8 (7.9%)
Immune system disorders	8 (7.9%)
Respiratory, thoracic and mediastinal disorders	7 (6.9%)
Psychiatric disorders	7 (6.9%)
Reproductive system and breast disorders	6 (5.9%)
Blood and lymphatic system disorders	4 (4.0%)
Eye disorders	4 (4.0%)
Concomitant medication, n, (%)
No	0 (0.0%)
Yes	60 (59.4%)
Not available	41 (40.6%)
Baseline PsO characterization
Mean age at diagnosis, years, SDc	35.3 (14.1)
Mean months since diagnosis, SDc	204.5 (197.4)
IGA scale, n (%)d
(0): Clear	0 (0.0%)
(1): Almost clear	0 (0.0%)
(2): Mild	9 (8.9%)
(3): Moderate	63 (62.4%)
(4): Severe	29 (28.7%)

This includes six events reported for three patients: cardiac insufficiency (1), major adverse cardiac event (1), arrhythmogenic ventricular cardiomyopathy (1), stroke (1), acute myocardial infarction (1), and arrhythmogenic ventricular cardiomyopathy (1)

SD standard deviation

^an = 100 patients

^bPercentage calculated over the total number of patients with at least one type of comorbidity (N = 79)

^cn = 18 patients

^dn = 101 patients

At baseline, most patients presented with moderate-to-severe disease based on the IGA scale, with 62.4% classified as moderate (IGA score 3) and 28.7% as severe (IGA score 4).

Most patients (90/101; 89.1%) had received at least one topical treatment for PsO prior to study entry (Table 2). Discontinuation of topical treatment was most often owing to lack of skin clearance (17.8%), while other reasons such as patient decision and side effects were less common (4.4% each). Notably, data on discontinuation reasons were unavailable for 80.0% of patients.

Table 2.

Previous therapies for PsO

Treatment
Topical treatment, n, (%)
Patients with at least one type of topical treatment	90 (89.1%)
Not available	11 (10.9%)
Main reason for discontinuation (n = 90)
Not achieving skin clearance	16 (17.8%)
Patient decision	4 (4.4%)
Side effects	4 (4.4%)
Other	19 (21.1%)
Not available	72 (80.0%)
Biological and/or systemic treatments, n, (%)
Patients with at least one type of biological and/or systemic treatment	90 (89.1%)
Not available	11 (10.9%)
Main reason for discontinuation (n = 90)
Loss of response	44 (48.9%)
No response	43 (47.8%)
Toxicity	33 (36.7%)
Physician decision due to reasons other than lack of effectiveness and toxicity	11 (12.2%)
Patient decision	4 (4.4%)
Other	2 (2.2%)
Not available	17 (18.9%)
Other therapies, n, (%)
Patients with at least one type of other therapy	32 (31.7%)
Not available	69 (68.3%)
Type of other therapy (in ≥ 4 patients)
Phototherapy	32 (100%)
PUVA	8 (25%)
UVB	23 (71.9%)
Main reason for discontinuation (n = 32)
No response	8 (25.0%)
Loss of response	8 (25%)
Patient decision	4 (12.5%)
Physician decision due to reasons other than lack of effectiveness and toxicity	3 (9.4%)
Toxicity	1 (3.1%)
Other	9 (28.1%)
Not available	8 (25.0%)

More than one reason for discontinuation per patient could be selected

A total of 90 patients (89.1%) had received at least one systemic and/or biological therapy (Table 2). Discontinuation was most frequently due to loss of response (48.9%) or primary nonresponse (47.8%), followed by toxicity (36.7%). Physician and patient decisions accounted for a smaller proportion of discontinuations. A total of 32 patients (31.7%) received prior phototherapy (Table 2) and reasons for discontinuation included no response or loss of response (each 25.0%), with other reasons such as patient decision, physician decision, or toxicity being less common.

Patient Satisfaction with Guselkumab One-Press Device Over 20 Weeks Based on the Self-Injection Assessment Questionnaire (SIAQ)

Assessment of the SIAQ PRE-module before injection (first injection at baseline) demonstrated statistically significant improvements across all domains between baseline and the 20-week follow-up (Fig. 1). Specifically, the mean score for Feelings about injections (FL) increased from 7.9 ± 2.3 at baseline to 8.4 ± 2.1 at week 20 (p = 0.014). The Confidence (CO) domain showed a substantial improvement from a mean of 6.3 ± 2.7 to 7.5 ± 2.4, and the Satisfaction (SA) domain increased markedly from 6.5 ± 2.9 to 8.9 ± 1.6, both with highly significant p-values (p < 0.001). Overall, the PRE module domain score rose from a baseline mean of 6.9 ± 1.8 to 8.3 ± 1.5, also with a statistically significant difference (p < 0.001).

Fig. 1.

Changes in SIAQ PRE–self-injection domain scores from baseline to week 20. Mean (± standard deviation) Self-Injection Assessment Questionnaire (SIAQ) PRE–self-injection domain scores at baseline (before the first guselkumab injection) and at week 20. Domains include feelings about injections (FL), confidence (CO), satisfaction (SA), and overall PRE-module score. Statistically significant improvements were observed across all domains between baseline and week 20. p values were calculated using the Wilcoxon signed-rank test. *p < 0.05; **p < 0.001

At baseline, most patients reported little or no fear of injections or needles (SIAQ items Q1 and Q2). However, more than 60% of patients expressed some degree of anxiety about self-administering the injection. This initial apprehension decreased with experience: by week 20, the proportion of patients reporting no anxiety about self-injection increased from 36.6% at baseline to 51.1% in the PRE module (Supplementary Table 1), and from 40.6 to 55.3% in the POST module (Supplementary Table 2). These findings indicate that patients not only gained confidence and satisfaction with repeated use of the One-Press device but also experienced a notable reduction in anxiety related to self-administration over time.

Favorable outcomes in the POST-module domains of the SIAQ from baseline through week 20 were also obtained (Fig. 2). Overall, patients maintained high levels of positive perceptions about the self-injection process, with modest but statistically significant improvements in several domains. The FL domain showed a slight increase in mean score from 8.2 ± 2.1 at baseline to 8.5 ± 1.9 at week 20 (p = 0.031). The CO domain improved significantly, increasing from a mean of 7.0 ± 2.7 to 7.8 ± 2.3 (p = 0.017), and SA domain rose from 8.2 ± 1.1 to 8.5 ± 1.2 (p = 0.017). The POST module domain score also showed a modest but statistically significant increase from 8.5 ± 1.0 to 8.7 ± 1.1 (p = 0.012). In contrast, no significant changes were observed in the injection site reactions (RE), ease of use (EU), or injection-related pain or discomfort (IM) domains, which remained consistently high throughout the study. These results indicate sustained or improved positive experiences with self-injection after repeated use, especially in terms of patients’ satisfaction and confidence.

Fig. 2.

Mean (± standard deviation) Self-Injection Assessment Questionnaire (SIAQ) POST–self-injection domain scores at baseline (after the first injection) and at week 20. Domains include feelings about injections (FL), injection-related pain or discomfort (IM), confidence (CO), injection-site reactions (RE), ease of use (EU), satisfaction (SA), and overall POST-module score. Scores remained high across domains, with statistically significant improvements observed in selected domains over time. p values were calculated using the Wilcoxon signed-rank test. *p < 0.05

Patient Quality of Life Variation with Guselkumab One-Press Device Based on the Dermatology Life Quality Index (DLQI) at Weeks 20 and 52

Assessment of quality of life using the DLQI scale demonstrated significant improvement over the 52-week treatment period. At baseline, the mean DLQI score was 8.5 ± 6.9, indicating a moderate to very large impact of psoriasis on patients’ lives. By week 20, the mean DLQI score had decreased to 1.5 ± 2.8, and further to 1.1 ± 3.0 by week 52 (Fig. 3); both changes were statistically significant compared with baseline (p < 0.001, Wilcoxon test).

Fig. 3.

Change in Dermatology Life Quality Index (DLQI) score from baseline to weeks 20 and 52. P-values are from Wilcoxon signed-rank tests comparing baseline with each follow-up time point

Median DLQI decreased from 7.0 at baseline to 0.5 and 0.0, at weeks 20 and 52, respectively, and over 70% of patients achieved a DLQI of 0/1 by week 20, indicating no impact of PsO on daily life (Supplementary Table 3).

The proportion of patients reporting no impact on quality of life (DLQI score 0/1) increased from 13.9% at baseline to 71.3% at week 20, and 82.0% at week 52 (Table 3). Consistent with this, the proportion of patients with a DLQI score > 2 decreased from 86.1% at baseline to 28.7% and 18.0% at weeks 20 and 52, respectively (p < 0.001, McNemar’s test; Table 3).

Table 3.

DLQI response at weeks 20 and 52 compared with baseline DLQI

Baseline DLQI	Follow-up week	Follow-up DLQI 0–1, n (%)	Follow-up DLQI ≥ 2, n (%)	Total, n (%)	p value (McNemar’s test versus baseline)
0–1	20	13 (13.8%)	1 (1.1%)	14 (14.9%)	< 0.001
> 2	20	54 (57.4%)	26 (27.7%)	80 (85.1%)
Total (week 20)		67 (71.3%)	27 (28.7%)	94 (100%)
0–1	52	10 (11.2%)	3 (3.4%)	13 (14.6%)	< 0.001
> 2	52	63 (70.8%)	13 (14.6%)	76 (85.4%)
Total (week 52)		73 (82.0%)	16 (18.0%)	89 (100%)

For analysis purposes, DLQI scores were grouped into two categories: 0–1, indicating no effect at all on the patient’s life, and > 2, indicating a small to extremely large effect on the patient’s life

Stratified analysis showed that among patients with DLQI > 2 at baseline, 67.5% (54/80) at week 20 and 82.9% (63/76) at week 52 achieved a DLQI score of 0/1, indicating a clinically meaningful improvement in quality of life (Table 3).

PsO Treatment Effectiveness Based on the 5-Point Investigator’s Global Assessment (IGA) Scale at Weeks 20 and 52

At baseline, the majority of patients were classified as having moderate (62.4%) or severe disease (28.7%), with a smaller proportion having mild disease (8.9%) (Table 4). By week 20, a dramatic improvement was observed, with 44.2% of patients assessed as clear (IGA 0) and 42.1% as almost clear (IGA 1). Improvements continued through week 52, when 65.2% were assessed as clear and 25.8% as almost clear (Table 4).

Table 4.

Distribution of patients by IGA score at baseline, week 20, and week 52

IGA scale	Baseline	20-week visit	52-week visit
	n = 101	n = 95	n = 89
IGA score, n, (%)
(0): Clear	0 (0.0%)	42 (44.2%)	58 (65.2%)
(1): Almost clear	0 (0.0%)	40 (42.1%)	23 (25.8%)
(2): Mild	9 (8.9%)	10 (10.5%)	6 (6.7%)
(3): Moderate	63 (62.4%)	3 (3.2%)	2 (2.2%)
(4): Severe	29 (28.7%)	0 (0.0%)	0 (0.0%)
IGA classified in categories, n, (%)
0–1	0 (0.0%)	82 (86.3%)	89 (91.0%)
> 2	101 (100.0%)	13 (13.7%)	8 (9.0%)

No patients in this real-world study were assessed as clear or almost clear (IGA score 0/1) at baseline. However, in week 20, 86.3% of patients achieved IGA 0/1 further increasing 91.0% at week 52 (Table 4). These findings underscore strong and sustained therapeutic responses as measured by the IGA scale, with most patients achieving almost complete or complete clearance of PsO by week 52.

Adverse Events

A total of 198 adverse events (AEs) were reported in 63 (62.4%) patients during the study period (Table 5). The most frequently reported AEs, occurring in > four patients, were localized reactions at the injection site. These included pain at the injection site (30 patients, 47.6%), burning sensation at the injection site (23 patients, 36.5%), hardening at the guselkumab injection site (19 patients, 30.2%), and swelling at the injection site (12 patients, 19.0%). Other commonly reported AEs included cold sensation at the injection site (9 patients, 14.3%), itching at the injection site (9 patients, 14.3%), PsO worsening (9 patients, 14.3%), and redness at the injection site (9 patients, 14.3%). Overall, 164 (82.8%) occurring in 57 patients were assessed as related to guselkumab, (Table 5). The remaining 34 events (17.2%) were considered unrelated.

Table 5.

Adverse events

Patients with at least one adverse event, n (%) (N = 101)
No	0 (0.0%)
Yes	63 (62.4%)
Not available	38 (37.6%)
Description of adverse events present in > four patients, n (%) (n = 63)
Pain at injection site	30 (47.6%)
Burning sensation at the injection site	23 (36.5%)
Hardening at the guselkumab injection site	19 (30.2%)
Swelling at the injection site	12 (19.0%)
Cold sensation at the injection site	9 (14.3%)
Itching at the injection site	9 (14.3%)
PsO worsening	9 (14.3%)
Redness at the injection site	9 (14.3%)
Adverse events related to guselkumab, n (%) (n = 198)
Not related	34 (17.2%)
Related	164 (82.8%)
Description of adverse events related to guselkumab present in > four patients, n (%) (n = 57)
Pain at injection site	30 (52.6%)
Burning sensation at the injection site	23 (40.4%)
Hardening at the guselkumab injection site	19 (33.3%)
Swelling at the injection site	10 (17.5%)
Cold sensation at the injection site	9 (15.8%)
PsO worsening	9 (15.8%)
Redness at the injection site	9 (15.8%)
Itching at the injection site	8 (14.0%)

The profile of guselkumab-related AEs largely mirrored the overall AE profile, with local injection site reactions again being the most prevalent. Pain at the injection site (30 patients, 52.6%), burning sensation (23 patients, 40.4%), and hardening at the injection site (19 patients, 33.3%) were most frequently observed. Additional guselkumab-related AEs included swelling at the injection site (10 patients, 17.5%), cold sensation at the injection site (9 patients, 15.8%), PsO worsening (9 patients, 15.8%), redness at the injection site (9 patients, 15.8%), and itching at the injection site (8 patients, 14.0%).

For AE reporting purposes in this study, all responses that were different than “not at all” in the Pain and Skin Reactions (RE) Domain of the POST Self-Injection Assessment Questionnaire (SIAQ) were reported as AEs.

No deaths were reported during the study period. A total of four serious AEs (SAEs) were documented, corresponding to 2.0% (4/198) of all reported adverse events (Table 6). These events occurred in four different patients included in the safety analysis set (n = 63). The reported SAEs included acute hepatitis (one patient; 1.6%); adenocarcinoma of the prostate (one patient; 1.6%); chronic obstructive pulmonary disease (one patient; 1.6%); low grade adenocarcinoma of the colon (one patient; 1.6%).

Table 6.

Serious adverse events

Number of adverse events considered serious adverse events, n (%) (n = 198)
No	194 (98.0%)
Yes	4 (2.0%)
Description of serious adverse events, n (%) (n = 63)
Acute hepatitis	1 (1.6%)
Adenocarcinoma of the prostate	1 (1.6%)
Chronic obstructive pulmonary disease	1 (1.6%)
Low grade adenocarcinoma of the colona	1 (1.6%)
Seriousness of serious adverse events, n (%) (n = 4)
Requires inpatient hospitalization or prolongation of existing hospitalization	3 (75.0%)
Life-threatening	1 (25.0%)
Adverse events leading to permanent treatment discontinuation, n (%) (n = 63)
No action taken	61 (96.8%)
Temporarily interrupted	4 (6.5%)
Permanently discontinued	2 (3.2%)

^aSerious adverse event considered related to guselkumab

Three events required inpatient hospitalization or prolongation of existing hospitalization, while one event was considered life-threatening. One SAE, low grade adenocarcinoma of the colon, was initially assessed as related to guselkumab (Table 6). Following further investigation, this SAE was determined to be unrelated to the study drug and likely confounded by advanced age and preexisting disease.

Two adverse events (3.2%) led to permanent discontinuation of the study treatment, while four events (6.5%) resulted in temporary treatment interruption. Most AEs (61 events; 96.8%) did not result in any change to study medication.

Discussion

This national real-world study evaluated patient satisfaction, quality of life, clinical effectiveness, and safety of guselkumab self-administered using the One-Press device in Portuguese patients with moderate-to-severe plaque PsO. Over the course of 52 weeks, self-administration of guselkumab with the One-Press device was associated with high satisfaction, meaningful improvements in health-related quality of life, and robust clinical effectiveness, consistent with pivotal clinical trial results.

Patients reported high satisfaction across all SIAQ domains at both the initial and week-20 assessments, with median scores exceeding 8.5 on a 10-point scale. Collectively, these findings suggest that the One-Press device was easy to use and, with repeated administration over 20 weeks, was associated with increased patient comfort, confidence, satisfaction, and reduced injection-related anxiety. Similar results were observed in the ORION trial for guselkumab (NCT02905331), in which 81–100% of patients were satisfied or very satisfied with the One-Press device [11]. Comparable outcomes have been reported in Spanish patients who preferred the One-Press device to the prefilled syringe, citing less pain and greater convenience [24]. Real-world and clinical studies evaluating self-injection devices for other biologics used in psoriasis and psoriatic arthritis have reported similarly favorable patient-reported experiences. For example, studies assessing autoinjector devices for secukinumab and adalimumab have shown high levels of patient satisfaction, improved confidence with self-injection, ease of use, and reduced injection-related anxiety compared with prefilled syringes or healthcare professional–administered injections, as measured by validated PROMs including SIAQ or device-specific questionnaires [12, 25]. The JUNCTURE trial demonstrated that secukinumab administered via autoinjector was associated with high usability and patient satisfaction [12], while real-world studies of adalimumab pens have reported improved patient confidence and preference for pen devices over syringes [25]. These findings are consistent with the improvements observed across SIAQ domains in the present study, supporting that the favorable patient experience with the guselkumab One-Press device aligns with broader real-world evidence for autoinjector systems in chronic inflammatory diseases.

Health-related quality of life, measured by the DLQI, improved markedly trough 52 weeks—the proportion of patients with DLQI score of 0/1 increased from 13.9% at baseline to 71.3% at week 20 and 82.0% at week 52. These outcomes are consistent with the VOYAGE 1 and VOYAGE 2 trials, in which guselkumab produced substantial and sustained improvements in DLQI [14], and with the NAVIGATE study, which demonstrated enhanced quality of life among patients inadequately controlled with ustekinumab [26]. Collectively, these findings reinforce the effectiveness of guselkumab in achieving meaningful patient-reported benefits under routine clinical conditions.

Despite nearly 90% of patients having prior exposure to biologic and/or systemic therapies, none had clear or almost clear skin (IGA 0/1) at baseline. Clinician-assessed outcomes demonstrated substantial improvement following guselkumab initiation, with 86.3% of patients achieving IGA 0/1 by week 20 and 91.0% by week 52. These findings are consistent with the VOYAGE trials, where 84.1% of patients achieved IGA 0/1 at week 16 with durable responses through week 48 [14], and with real-world data from the CorEvitas PsO Registry reporting 64.6% achieving IGA 0/1 after 9–12 months of treatment [27]. While psoriasis worsening was reported in nine patients, the IGA score increased from baseline in only two patients, and both discontinued treatment. The remaining seven patients showed overall improvement in IGA score from baseline.

Recent transcriptomic analyses have provided further insight into the molecular mechanisms underlying psoriasis and its response to targeted biologic therapies. Studies using lesional and nonlesional skin have demonstrated that psoriasis is characterized by a distinct inflammatory transcriptomic profile dominated by the IL-23–Th17 axis, and that effective interleukin (IL)-23 inhibition leads to normalization of psoriasis-associated gene expression patterns and restoration toward nonlesional skin profiles [28, 29]. These molecular findings support the sustained clinical efficacy observed with guselkumab and may help explain the durable skin clearance and improvements in patient-reported outcomes seen in both clinical trials and real-world studies, including the present CERES study. While transcriptomic analyses were beyond the scope of this study, such data provide important biological context for the robust and persistent treatment responses observed.

The safety profile was favorable and consistent with previously published data [14, 26, 27, 30]. Most AEs were mild, transient, related to local injection-site reactions such as pain, burning, or redness, consistent with known effects of subcutaneous administration. Any positive answers to the SIAQ domain of “Pain and skin reactions during or after the injection” were reported as adverse events. By incorporating the SIAQ responses into AE Reporting may have inflated the incidence observed by essentially soliciting reports of injection-site sensations rather than what is typically considered injection-sire reactions. This may lead to an increase in detecting minor events and reflecting subjective perceptions varying between individuals.

Four serious adverse events (2.0%) occurred, with only one (low-grade colon adenocarcinoma) initially assessed as related to treatment; however, following further investigation, the event was determined to be unrelated to the study drug and likely confounded by advanced age and preexisting disease. Discontinuation due to AEs was rare (1.0%), and no new safety signals occurred during follow-up. Importantly, no systemic hypersensitivity reactions or AESIs related to guselkumab were reported through week 52. There were no reports of AEs related to serious infections requiring treatment, major cardiovascular events, or inflammatory bowel disease. Despite the inclusion of a patient population with a high burden of comorbidities (76% of patients having at least one comorbidity and 30% presenting with three or more) the overall safety findings remained consistent with the established favorable safety profile of guselkumab observed in previous psoriasis trials [14, 26, 27, 30]. Further, these findings confirm the favorable benefit–risk profile of guselkumab and the tolerability of the One-Press device for the treatment of moderate-to-severe plaque psoriasis.

This study has several limitations that should be acknowledged. The open-label, single-arm design without a control group limits causal inference and may introduce reporting bias, particularly for PROs. The sample size was adequate for descriptive analyses but insufficient for robust subgroup comparisons, and long-term data are needed to evaluate durability of response and safety beyond 1 year. Moreover, use of the SIAQ may have solicited reporting of AEs given its nature, leading to higher rates of AEs compared with other studies. Seasonal variation, which is known to influence psoriasis activity, quality of life, and patient-reported outcomes, was not specifically evaluated, and no analyses stratified by season were performed. In addition, clinical effectiveness was assessed exclusively using the IGA; although widely used and validated, the absence of other objective measures such as Psoriasis Area Severity Index or body surface area limits the comprehensiveness of effectiveness evaluation. Finally, as the study was conducted exclusively in Portugal, regional healthcare practices and cultural factors may influence generalizability of the findings. Nonetheless, the consistency of these findings with international studies supports their external validity.

Conclusions

Guselkumab self-administered using the One-Press device demonstrated high patient satisfaction, substantial improvements in quality of life, and sustained clinical effectiveness over 52 weeks in Portuguese patients with moderate-to-severe plaque PsO, in alignment with previous findings. Treatment was well-tolerated, with safety findings consistent with previous studies. These results provide real-world confirmation of the efficacy, usability, and acceptability of guselkumab self-administered using the One-Press device as a convenient, effective, and well-tolerated therapeutic option for patients with moderate-to-severe PsO.

Supplementary Information

Below is the link to the electronic supplementary material.

Author Contributions

Study conception and design: Diana Lourenço. National Study Coordinator: Tiago Torres. Tiago Torres, João Teles Sousa, Joana Antunes, Pedro Mendes-Bastos, Ana Brasileiro, Vitor Neto, Martinha Henrique, Rita Pimenta, Sofia Magina, Fernando Mota, and Diana Lourenço were involved in reviewing the article critically for important intellectual content, and all authors approved the final version to be submitted for publication.

Funding

Funding for this research, and the journal’s Rapid Service fee, was provided by Johnson & Johnson (Protocol CNTO1959PSO4021).

Data Availability

The datasets generated and/or analyzed during the current study are available from the corresponding author upon reasonable request.

Declarations

Conflicts of Interest

The authors declare the following conflicts of interest: Tiago Torres: AbbVie, Almirall, Amgen, Apogee Therapeutics, Arena Pharmaceuticals, Biocad, Biogen, Boehringer Ingelheim, Bristol Myers-Squibb, Celgene, Eli-Lilly, Fresenius-Kabi, Johnson & Johnson, LEO Pharma, MSD, Mylan, Novartis, Pfizer, Samsung Bioepis, Sanofi- Genzyme, Sandoz, STADA, UCB, Viatris. Conflict of Interest’ section: Tiago Torres is an Editorial Board member of Dermatology and Therapy. Tiago Torres was not involved in the selection of peer reviewers for the manuscript nor any of the subsequent editorial decisions. João Teles Sousa: AbbVie, Eli-Lilly, Johnson & Johnson, LEO Pharma. Joana Antunes: AbbVie, Almirall, Amgen, Boehringer Ingelheim, Johnson & Johnson, LEO Pharma, Lilly, Moonlake Immunotherapeutics, Novartis and Sanofi. Pedro Mendes-Bastos: AbbVie, Almirall, Alumis, Amgen, Apogee,, Biogen, Cantabria Labs, CS Labs, Eli-Lilly, Evelo Biosciences, GlaxoSmithKline, Johnson & Johnson, LEO Pharma, L’Oréal,Novartis, Organon, Pfizer, Pierre Fabre, Regeneron, Sanofi, Sanofi-Regeneron, Takeda, Teva and Viatris. Ana Brasileiro: AbbVie, Almirall, Biogen, Eli-Lilly, Johnson & Johnson, LEO Pharma, Novartis, and Sanofi. Vitor Neto: AbbVie, Johnson & Johnson. Martinha Henrique: AbbVie, Almirall, Johnson & Johnson, Novartis, LEO Pharma, Eli-Lilly, and Sanofi. Rita Pimenta: AbbVie, Almirall, Johnson & Johnson, LEO Pharma, Novartis. Sofia Magina: Abbvie, Almirall, Amgen, Eli-Lilly, Johnson & Johnson, Leo-Pharma, MSD, Novartis, Pfizer, Sanofi. Fernando Mota: Abbvie, Almirall, Amgen, Boehringer Ingelheim, Galderma, Johnson & Johnson, LEO Pharma, Lilly, Novartis, Organon, Pfizer, Pierre Fabre, Sanofi Genzyme. These disclosures reflect engagements in roles such as consultancy, advisory, speaker participation, or involvement in clinical research. Diana Lourenço is an employee of Johnson & Johnson Innovative Medicine, Portugal.

Ethical Approval

The study was conducted in accordance with the Declaration of Helsinki and was approved by the institutional review board or independent ethics committee at each participating center. The CERES study was a national, prospective, noninterventional, real-world observational study conducted under routine clinical practice in Portugal, with no assignment of treatment, no randomization, and no deviation from standard of care; all treatment decisions were made independently by the treating physicians prior to and irrespective of study participation. In accordance with applicable national and international regulations, non-interventional observational studies of this nature are not required to be registered in public clinical trial registries. The study was conducted in compliance with all ethical and regulatory requirements, and written informed consent was obtained from all patients prior to inclusion.