Real-World Observational Study on the Characteristics and Treatment Patterns of Allergic Asthma Patients Receiving Omalizumab in Canada

Figures & data

Figure 1 Schematic representation of the study time frame with the purpose of each time period.

Table 1 Characteristics of the Study Cohort (N=1160) at Their Index Date

Characteristic	Descriptive Statistics
Age (y)	Mean (SD)	45.8 (15.2)
	Median (IQR)	47.0 (19.0)
	Minimum/Maximum	12/88
Characteristic	Category	n (%) of patients
Age group (y)	12–19	98 (8.4)
	20–34	137 (11.8)
	35–49	435 (37.5)
	50–64	363 (31.3)
	65 and older	127 (10.9)
Sex^a	Female	748 (64.7)
	Male	408 (35.3)
Province of residence^b	Ontario	733 (64.0)
	Quebec	290 (25.3)
	Alberta	58 (5.1)
	Atlantic provinces (NB, NL, NS, PEI)	38 (3.3)
	Prairies (SK, MB)	6 (0.5)
	British Columbia	20 (1.7)
Drug insurer	PDP	860 (74.1)
	ODBP	254 (21.9)
	RAMQ	46 (4.0)

Notes: ^aData on sex were missing for four patients and thus the above represents the sex for 1156 of 1160 patients. ^bProvince of residence was missing for 15 patients and thus the above represents the provincial distribution for 1145 of 1160 patients.

Abbreviations: IQR, interquartile range; MB, Manitoba; n, number; NB, New Brunswick; NL, Newfoundland and Labrador; NS, Nova Scotia; ODBP, Ontario Drug Benefit Plan; PDP, private drug plan; PEI, Prince Edward Island; RAMQ, Régie de l’Assurance Maladie du Québec; SD, standard deviation; SK, Saskatchewan; y, years.

Figure 2 Order and results of applying the algorithm’s inclusion and exclusion criteria in the IQVIA claims database to construct the study cohort.

Table 2 Analysis of Potential Predictors of Omalizumab Discontinuation Over a 3-Year Period Using the Cox Proportional Hazards Model (Multivariable Regression Method)

Variable	Category	Hazard Ratio (95% CI)	P-value
Sex	Female	1.00^a	n/a
	Male	1.03 (0.84,1.25)	0.80
Age group (y)	12–19	1.00^a	n/a
	20–34	1.75 (1.11, 2.76)	0.02
	35–64	1.29 (0.88, 1.90)	0.19
	65 and older	1.14 (0.68, 1.92)	0.62
Province of residence	Ontario	1.00^a	n/a
	Quebec	0.81 (0.63, 1.05)	0.11
	Alberta	1.20 (0.80, 1.80)	0.37
	Atlantic provinces (NB, NL, NS, PEI)	1.05 (0.60, 1.84)	0.87
	Prairies (SK, MB)	0.55 (0.08, 3.93)	0.55
	British Columbia	1.14 (0.54, 2.43)	0.74
Drug insurer	PDP	1.00^a	n/a
	ODBP	0.85 (0.63, 1.13)	0.26
	RAMQ	0.98 (0.59, 1.65)	0.95

Notes: ^aIndicates the reference variable in a particular variable group. Bolded values are statistically significant.

Abbreviations: CI, confidence interval; MB, Manitoba; n/a, not applicable; NB, New Brunswick; NL, Newfoundland and Labrador; NS, Nova Scotia; ODBP, Ontario Drug Benefit Plan; PDP, Private drug plan; PEI, Prince Edward Island; RAMQ, Régie de l’assurance maladie du Québec; SK, Saskatchewan; y, years.

Figure 3 Kaplan–Meier curve of omalizumab persistence and discontinuation.

Table 3 Use of Concurrent Medications Before, During, and After Omalizumab Usage for Patients Who Discontinued Omalizumab (n=433)

Concurrent Medication	Before Omalizumab Use	During Omalizumab Use	After Omalizumab Use
SABA	55.7%	59.1%	54.3%
ICS plus LABA	67.0%	61.9%	59.6%
ICS	33.5%	34.2%	28.9%
LAMA	20.1%	20.6%	19.2%
Xanthine	6.0%	6.9%	5.5%
LABA	5.8%	4.6%	3.9%
LTRA	39.7%	31.0%	26.3%
OCS	59.1%	48.7%	44.8%

Abbreviations: ICS, inhaled corticosteroid; LABA, long-acting β₂-agonist; LAMA, long-acting muscarinic antagonist; LTRA, leukotriene receptor antagonist; OCS, oral corticosteroid; SABA, short-acting β₂-agonist.

Table 4 Changes in the Percentage of Patients Using Concurrent Medications Before, During, and After Omalizumab Therapy for Patients Who Discontinued Omalizumab (n=433) Evaluated Using McNemar’s Test

Concurrent Medication	Before vs During		During vs After		Before vs After
	Difference (95% CI)	P-value	Difference (95% CI)	P-value	Difference (95% CI)	P-value
SABA	−3.46 (−8.43, 1.50)	0.21	4.85 (−0.23, 9.93)	0.08	1.39 (−3.18, 5.96)	0.62
LAMA	−0.46 (−3.46, 2.54)	0.88	1.38 (−1.68, 4.45)	0.46	0.92 (−2.21, 4.06)	0.67
Xanthine	−0.93 (−2.20, 0.35)	0.29	1.39 (−0.3, 3.07)	0.18	0.46 (−1.23, 2.16)	0.79
LABA	1.15 (−0.47, 2.78)	0.27	0.69 (−0.66, 2.05)	0.51	1.84 (−0.06, 3.76)	0.10
ICS/LABA	5.08 (0.86, 9.30)	0.02	2.31 (−1.83, 6.45)	0.33	7.39 (2.96, 11.82)	0.002
ICS	−0.69 (−4.66, 3.28)	0.82	5.31 (1.37, 9.25)	0.01	4.62 (0.30, 8.94)	0.047
LTRA	8.77 (5.14, 12.42)	<0.001	4.62 (1.02, 8.21)	0.02	13.39 (9.49, 17.29)	<0.001
OCS	10.39 (5.03, 15.75)	<0.001	3.93 (−1.20, 9.05)	0.16	14.32 (9.14, 19.50)	<0.001

Note: Bolded values are statistically significant.

Abbreviations: CI, confidence interval; ICS, inhaled corticosteroid; LABA, long-acting β₂-agonist; LAMA, long-acting muscarinic antagonist; LTRA, leukotriene receptor antagonist; OCS, oral corticosteroid; SABA, short-acting β₂-agonist.