Treatment patterns and healthcare costs among patients with psoriasis initiating apremilast or biologics: a retrospective claims database cohort analysis

Figures & data

Figure 1. Patient attrition flow chart. AS: ankylosing spondylitis; Ili: interleukin inhibitor; JIA: juvenile idiopathic arthritis; PSA: psoriatic arthritis; PsO: psoriasis; RA: rheumatoid arthritis; TNFi: tumor necrosis factor inhibitor; UC: ulcerative colitis.

Table 1. Baseline demographic and clinical characteristics post-propensity score matching.

Patient demographic or characteristic	Overall (N = 2535)	Apremilast (n = 845)	TNFi (n = 845)	ILi (n = 845)	p Value^a
Age, mean (SD), y	49.4 (15.3)	49.5 (15.7)	49.6 (14.9)	49.0 (15.2)	.728
Female, n (%)	1115 (44.0)	371 (43.9)	388 (45.9)	356 (42.1)	.292
CCI, mean (SD)	0.49 (1.1)	0.49 (1.1)	0.50 (1.1)	0.48 (1.0)	.796
Concomitant medications, n (%)
Oral steroids	581 (22.9)	202 (23.9)	190 (22.5)	189 (22.4)	.704
Oral systemics	394 (15.5)	134 (15.9)	125 (14.8)	135 (16.0)	.761
Phototherapy	163 (6.4)	54 (6.4)	57 (6.7)	52 (6.2)	.883
Topicals	1831 (72.2)	614 (72.7)	618 (73.1)	599 (70.9)	.553
Index therapy, n (%)
Apremilast	845 (33.3)	845 (100)	0 (0.0)	0 (0.0)	NA
Adalimumab	748 (29.5)	0 (0.0)	748 (88.5)	0 (0.0)
Certolizumab pegol	2 (0.1)	0 (0.0)	2 (0.2)	0 (0.0)
Etanercept	95 (3.8)	0 (0.0)	95 (11.2)	0 (0.0)
Infliximab	0 (0.0)	0 (0.0)	0 (0.0)	0 (0.0)
Ustekinumab	576 (22.7)	0 (0.0)	0 (0.0)	576 (68.2)
Brodalumab	2 (0.1)	0 (0.0)	0 (0.0)	2 (0.2)
Secukinumab	119 (4.7)	0 (0.0)	0 (0.0)	119 (14.1)
Ixekizumab	49 (1.9)	0 (0.0)	0 (0.0)	49 (5.8)
Guselkumab	98 (3.9)	0 (0.0)	0 (0.0)	98 (11.6)
Tildrakizumab	1 (0.0)	0 (0.0)	0 (0.0)	1 (0.1)
Risankizumab	0 (0.0)	0 (0.0)	0 (0.0)	0 (0.0)

CCI: Charlson Comorbidity Index; Ili: interleukin inhibitor; NA: not applicable; TNFi: tumor necrosis factor α inhibitor.

^aChi-square test for categorical variables and Kruskal–Wallis test for continuous variables.

Figure 2. Switch rates over 24 months of follow-up. IL: interleukin; TNF: tumor necrosis factor.

Figure 3. Kaplan–Meier curve for time to treatment modification in months, N = 6558. IL: interleukin; N/No.: number; TNF: tumor necrosis factor.

Table 2. HCRU and costs before and after switching during a 24-month follow-up period^a.

24-Month follow-up period	Statistics	Apremilast (n = 175)		TNF inhibitors (n = 274)		IL inhibitors (n = 122)		p Value^b (pre-switch)	p Value^b (post-switch)
		Pre-switch	Post-switch	Pre-switch	Post-switch	Pre-switch	Post-switch
PPPM HCRU visits	Mean	3.49	3.23	3.71	3.41	3.31	4.01	.155	.118
	SD	3.19	2.35	2.48	2.48	2.16	3.61
PPPM healthcare cost^c	Mean	$2560	$6923	$5207	$7109	$5616	$8378	< .001	.685
	SD	$2064	$6467	$2519	$5840	$2871	$9959

HCRU: healthcare resource utilization; IL: interleukin; PPPM: per person per month; TNF: tumor necrosis factor.

^aFor patients who switched treatment within 24 months.

^bp Value generated through Kruskal–Wallis test.

^cThere were approximately 1% of patients with a pre-switch PPPM healthcare cost greater than $16,000; those values were top capped at $16,000, while post-switch PPPM healthcare costs were capped at $53,000 (top 1%). All other PPPM costs were recalculated based on the proportion spent and adjusted backward.

Data availability statement

Data for these analyses were made available to the authors through third-party license from Optum Clinformatics^® Data Mart, a commercial data provider in the United States. As such, the authors cannot make these data publicly available due to a data use agreement. Other researchers can access these data by purchasing a license through Optum Clinformatics^® Data Mart. Inclusion criteria specified in the Methods section would allow other researchers to identify the same cohort of patients used for these analyses. Interested parties may see https://www.optum.com/business/life-sciences/real-world-data/claims-data.html for more information on Optum Clinformatics^® Data Mart.