A multicenter evaluation of the efficacy and duration of action of alcaftadine 0.25% and olopatadine 0.2% in the conjunctival allergen challenge model

Figures & data

Table 1 Demographics (intent-to-treat population)

Characteristic	Alcaftadine 0.25% n = 43	Olopatadine 0.2% n = 43	Placebo n = 41	All subjects n = 127	P value
Age					0.634
Mean ± SD	39.3 ± 12.4	37.0 ± 14.8	39.3 ± 12.3	38.5 ± 13.2
Min–max	15–64	12–74	14–61	12–74
Gender, n (%)					0.726
Male	12 (28)	10 (23)	13 (32)	35 (28)
Female	31 (72)	33 (77)	28 (68)	92 (72)
Ethnicity, n (%)					0.496
Hispanic or Latino	5 (11.6)	9 (20.9)	5 (12.2)	19 (15)
Not Hispanic or Latino	38 (88.4)	34 (79.1)	36 (87.8)	108 (85)
Race, n					0.316
African American	5	2	6	13
Caucasian	34	34	33	101
Other	4	7	2	13
Iris color, n					0.062
Blue	20	24	16	60
Brown	50	46	46	142
Hazel	4	12	6	22
Green	12	4	12	28
Gray	0	0	2	2

Abbreviations: min, minimum; max, maximum; P, probability level; SD, standard deviation.

Figure 1 Comparison of ocular itching scores at 16 hours (A) and at 24 hours (B) after instillation of treatment. Mean itching for placebo, alcaftadine 0.25%, and olopatadine 0.2% at 3, 5, and 7 minutes after allergen challenge.

Table 2 Summary of ocular itching results (intent-to-treat population): differences versus placebo in mean ocular itching scores following CAC for alcaftadine 0.25% and olopatadine 0.2% at 16 and 24 hours

Time point post-CAC	Visit 3			Visit 4
	Duration of action 16 hours following study treatment			Duration of action 24 hours following study treatment
	3 min	5 min	7 min	3 min	5 min	7 min
Active versus placebo
Alcaftadine-placebo	−1.53	−1.43	−1.13	−1.63	−1.35	−1.02
P value	<0.0001	<0.0001	<0.0001	<0.0001	<0.0001	<0.0001
Olopatadine-placebo	−1.14	−1.22	−1.08	−1.30	−1.03	−0.94
P value	<0.0001	<0.0001	<0.0001	<0.0001	<0.0001	<0.0001
Active versus active
Alcaftadine-olopatadine	−0.39	−0.20	−0.05	−0.33	−0.32	−0.08
P value	0.026	0.273	0.798	0.073	0.117	0.710

Abbreviations: CAC, conjunctival allergen challenge; min, minutes; P, probability level.

Figure 2 Reduction from baseline itch scores. A comparison of itch scores at visit 3 (16 hours; A) and at visit 4 (24 hours; B) with those from visit 2 (pretreatment baseline visit).

Figure 3 Comparison of minimal itch (scores < 1) data for placebo, alcaftadine 0.25%, and olopatadine 0.2% at 16 hours (A) and at 24 hours (B) after instillation of treatment.

Figure 4 Comparison of zero itch data for placebo, alcaftadine 0.25%, and olopatadine 0.2% at 16 hours (A) and 24 hours (B) after instillation of treatment.

Figure 5 Percent of total subject-reported itching scores in each treatment group (A–C).

Table 3 Secondary endpoint data for both visits expressed as difference scores

Time point post-CAC	Visit 3			Visit 4
	Duration of action 16 hours post study treatment			Duration of action 24 hours post study treatment
	7 min	15 min	20 min	7 min	15 min	20 min
Conjunctival redness
Alcaftadine 0.25%-placebo	−0.21	−0.26	−0.24	−0.34a	−0.22	−0.21
Olopatadine 0.2%-placebo	−0.33a	−0.30a	−0.25	−0.30a	−0.21	−0.28
Alcaftadine 0.25%-olopatadine 0.2%	0.11	0.04	0.01	−0.04	−0.01	0.07
Ciliary redness
Alcaftadine 0.25%-placebo	−0.43a	−0.30a	−0.28	−0.48a	−0.36a	−0.26
Olopatadine 0.2%-placebo	−0.45a	−0.32a	−0.29	−0.36a	−0.33	−0.28
Alcaftadine 0.25%-olopatadine 0.2%	0.02	0.02	0.01	−0.12	−0.03	0.02
Episcleral redness
Alcaftadine 0.25%-placebo	−0.22	−0.31	−0.16	−0.36a	−0.19	−0.22
Olopatadine 0.2%-placebo	−0.38a	−0.36a	−0.29	−0.45a	−0.33	−0.35
Alcaftadine 0.25%-olopatadine 0.2%	0.16	0.06	0.13	0.09	0.13	0.13
Chemosis
Alcaftadine 0.25%-placebo	−0.35a	−0.49a	−0.41a	−0.25a	−0.31a	−0.28a
Olopatadine 0.2%-placebo	−0.27a	−0.42a	−0.38a	−0.18	−0.25	−0.29
Alcaftadine 0.25%-olopatadine 0.2%	−0.08	−0.06	−0.02	−0.07	−0.05	0.01
Lid swelling
Alcaftadine 0.25%-placebo	−0.7a	−0.8a	−0.7a	−0.6a	−0.5a	−0.5a
Olopatadine 0.2%-placebo	−0.5a	−0.6a	−0.6a	−0.6a	−0.4a	−0.5a
Alcaftadine 0.25%-olopatadine 0.2%	−0.1	−0.2	−0.1	0.0	−0.1	0.0
Tearing
Alcaftadine 0.25%-placebo	−0.6a	−0.5a	−0.6a	−0.7a	−0.4a	−0.3
Olopatadine 0.2%-placebo	−0.4a	−0.3	−0.4	−0.6a	−0.3	−0.3
Alcaftadine 0.25%-olopatadine 0.2%	−0.1	−0.2	−0.2	−0.1	−0.1	0.0

Notes: Data are from the intent-to-treat population.

a P < 0.005 versus placebo using a two-sided t-test.

Abbreviations: CAC, conjunctival allergen challenge; min, minutes.