Tadalafil (Page 9 of 11)

14.2 Tadalafil for Once Daily Use for ED

The efficacy and safety of tadalafil for once daily use in the treatment of erectile dysfunction has been evaluated in 2 clinical trials of 12-weeks duration and 1 clinical trial of 24-weeks duration, involving a total of 853 patients. Tadalafil, when taken once daily, was shown to be effective in improving erectile function in men with erectile dysfunction (ED).

Tadalafil was studied in the general ED population in 2 randomized, multicenter, double-blinded, placebo-controlled, parallel-arm design, primary efficacy and safety studies of 12- and 24-weeks duration, respectively. One of these studies was conducted in the United States and one was conducted in centers outside the U.S. An additional efficacy and safety study was performed in ED patients with diabetes mellitus. Tadalafil was taken once daily at doses ranging from 2.5 to 10 mg. Food and alcohol intake were not restricted. Timing of sexual activity was not restricted relative to when patients took tadalafil.

Results in General ED Population — The primary U.S. efficacy and safety trial included a total of 287 patients, with a mean age of 59 years (range 25 to 82 years). The population was 86% White, 6% Black, 6% Hispanic, and 2% of other ethnicities, and included patients with ED of various severities, etiologies (organic, psychogenic, mixed), and with multiple co-morbid conditions, including diabetes mellitus, hypertension, and other cardiovascular disease. Most (>96%) patients reported ED of at least 1-year duration.

The primary efficacy and safety study conducted outside the U.S. included 268 patients, with a mean age of 56 years (range 21 to 78 years). The population was 86% White, 3% Black, 0.4% Hispanic, and 10% of other ethnicities, and included patients with ED of various severities, etiologies (organic, psychogenic, mixed), and with multiple co-morbid conditions, including diabetes mellitus, hypertension, and other cardiovascular disease. Ninety-three percent of patients reported ED of at least 1-year duration.

In each of these trials, conducted without regard to the timing of dose and sexual intercourse, tadalafil demonstrated clinically meaningful and statistically significant improvement in erectile function, as measured by the EF domain of the IIEF questionnaire and Questions 2 and 3 of the SEP diary (see Table 17). When taken as directed, tadalafil was effective at improving erectile function.

In the 6 month double-blind study, the treatment effect of tadalafil did not diminish over time.

Table 17: Mean Endpoint and Change from Baseline for the Primary Efficacy Variables in the Two Tadalafil for Once Daily Use Studies

	Study H a				Study I b
	Placebo	Tadalafil 2.5 mg	Tadalafil 5 mg		Placebo	Tadalafil 5 mg
	(N=94)	(N=96)	(N=97)	p-value	(N=54)	(N=109)	p-value
EF Domain Score
Endpoint	14.6	19.1	20.8		15.0	22.8
Change from baseline	1.2	6.1 c	7.0 c	<.001	0.9	9.7 c	<.001
Insertion of Penis (SEP2)
Endpoint	51%	65%	71%		52%	79%
Change from baseline	5%	24% c	26% c	<.001	11%	37% c	<.001
Maintenance of Erection (SEP3)
Endpoint	31%	50%	57%		37%	67%
Change from baseline	10%	31% c	35% c	<.001	13%	46% c	<.001

^a Twenty-four-week study conducted in the U.S.

^b Twelve-week study conducted outside the U.S.

^c Statistically significantly different from placebo.

Efficacy Results in ED Patients with Diabetes Mellitus — Tadalafil for once daily use was shown to be effective in treating ED in patients with diabetes mellitus. Patients with diabetes were included in both studies in the general ED population (N=79). A third randomized, multicenter, double-blinded, placebo-controlled, parallel-arm design trial included only ED patients with type 1 or type 2 diabetes (N=298). In this third trial, tadalafil demonstrated clinically meaningful and statistically significant improvement in erectile function, as measured by the EF domain of the IIEF questionnaire and Questions 2 and 3 of the SEP diary (see Table 18).

Table 18: Mean Endpoint and Change from Baseline for the Primary Efficacy Variables in a Tadalafil for Once Daily Use Study in ED Patients with Diabetes

	Placebo	Tadalafil 2.5 mg	Tadalafil 5 mg
	(N=100)	(N=100)	(N=98)	p-value
EF Domain Score
Endpoint	14.7	18.3	17.2
Change from baseline	1.3	4.8 a	4.5 a	<.001
Insertion of Penis (SEP2)
Endpoint	43%	62%	61%
Change from baseline	5%	21% a	29% a	<.001
Maintenance of Erection (SEP3)
Endpoint	28%	46%	41%
Change from baseline	8%	26% a	25% a	<.001

^a Statistically significantly different from placebo.

14.3 Tadalafil 5 mg for Once Daily Use for Benign Prostatic Hyperplasia (BPH)

The efficacy and safety of tadalafil for once daily use for the treatment of the signs and symptoms of BPH was evaluated in 3 randomized, multinational, double-blinded, placebo-controlled, parallel-design, efficacy and safety studies of 12 weeks duration. Two of these studies were in men with BPH and one study was specific to men with both ED and BPH [see Clinical Studies ( 14.4)]. The first study (Study J) randomized 1,058 patients to receive either tadalafil 2.5 mg, 5 mg, 10 mg or 20 mg for once daily use or placebo. The second study (Study K) randomized 325 patients to receive either tadalafil 5 mg for once daily use or placebo. The full study population was 87% White, 2% Black, 11% other races; 15% was of Hispanic ethnicity. Patients with multiple co-morbid conditions such as diabetes mellitus, hypertension, and other cardiovascular disease were included.

The primary efficacy endpoint in the two studies that evaluated the effect of tadalafil for the signs and symptoms of BPH was the International Prostate Symptom Score (IPSS), a four week recall questionnaire that was administered at the beginning and end of a placebo run-in period and subsequently at follow-up visits after randomization. The IPSS assesses the severity of irritative (frequency, urgency, nocturia) and obstructive symptoms (incomplete emptying, stopping and starting, weak stream, and pushing or straining), with scores ranging from 0 to 35; higher numeric scores representing greater severity. Maximum urinary flow rate (Q _max ), an objective measure of urine flow, was assessed as a secondary efficacy endpoint in Study J and as a safety endpoint in Study K.

The results for BPH patients with moderate to severe symptoms and a mean age of 63.2 years (range 44 to 87) who received either tadalafil 5 mg for once daily use or placebo (N=748) in Studies J and K are shown in Table 19 and Figures 5 and 6, respectively.

In each of these 2 trials, tadalafil 5 mg for once daily use resulted in statistically significant improvement in the total IPSS compared to placebo. Mean total IPSS showed a decrease starting at the first scheduled observation (4 weeks) in Study K and remained decreased through 12 weeks.

Table 19: Mean IPSS Changes in BPH Patients in Two Tadalafil for Once Daily Use Studies

	Study J			Study K
	Placebo	Tadalafil 5 mg		Placebo	Tadalafil 5 mg
	(N=205)	(N=205)	p-value	(N=164)	(N=160)	p-value
Total Symptom Score (IPSS)
Baseline	17.1	17.3		16.6	17.1
Change from Baseline to Week 12	-2.2	-4.8	<.001	-3.6	-5.6	.004

Figure 5: Mean IPSS Changes in BPH Patients by Visit in Study J

Figure 6: Mean IPSS Changes in BPH Patients by Visit in Study K

In Study J, the effect of tadalafil 5 mg once daily on maximum urinary flow rate (Q _max ) was evaluated as a secondary efficacy endpoint. Mean Q _max increased from baseline in both the treatment and placebo groups (tadalafil 5 mg: 1.6 mL/sec, placebo: 1.2 mL/sec); however, these changes were not significantly different between groups.

In Study K, the effect of tadalafil 5 mg once daily on Q _max was evaluated as a safety endpoint. Mean Q _max increased from baseline in both the treatment and placebo groups (tadalafil 5 mg: 1.6 mL/sec, placebo: 1.1 mL/sec); however, these changes were not significantly different between groups.

Efficacy Results in Patients with BPH initiating Tadalafil and Finasteride – Tadalafil for once daily use initiated together with finasteride was shown to be effective in treating the signs and symptoms of BPH in men with an enlarged prostate (>30 cc) for up to 26 weeks. This additional double-blinded, parallel-design study of 26 weeks duration randomized 696 men to initiate either tadalafil 5 mg with finasteride 5 mg or placebo with finasteride 5 mg. The study population had a mean age of 64 years (range 46 to 86). Patients with multiple co-morbid conditions such as erectile dysfunction, diabetes mellitus, hypertension, and other cardiovascular disease were included.

Tadalafil with finasteride demonstrated statistically significant improvement in the signs and symptoms of BPH compared to placebo with finasteride, as measured by the total IPSS at 12 weeks, the primary study endpoint (see Table 20). Key secondary endpoints demonstrated improvement in total IPSS starting at the first scheduled observation at week 4 (Tadalafil -4, placebo -2.3: p<.001) and the score remained decreased through 26 weeks (Tadalafil -5.5, placebo -4.5; p=.022). However, the magnitude of the treatment difference between placebo/finasteride and tadalafil/finasteride decreased from 1.7 points at Week 4 to 1 point at Week 26, as shown in Table 20 and in Figure 7. The incremental benefit of tadalafil beyond 26 weeks is unknown.

Table 20: Mean Total IPSS Changes in BPH Patients in a Tadalafil for Once Daily Use Study Together with Finasteride

		Placebo and finasteride 5 mg		Tadalafil 5mg and finasteride 5 mg	Treatment difference
	n	(N=350) a	n	(N=345) a		p-value b
Total Symptom Score (IPSS)
Baseline c	349	17.4	344	17.1
Change from Baseline to Week 4b	340	-2.3	330	-4.0	-1.7	<.001
Change from Baseline to Week 12b	318	-3.8	317	-5.2	-1.4	.001
Change from Baseline to Week 26b	295	-4.5	308	-5.5	-1.0	.022

^a Overall ITT population.
^b Mixed model for repeated measurements. ^c Unadjusted mean.

Figure 7: Mean Total IPSS Changes By Visit in BPH Patients Taking Tadalafil for Once Daily Use Together With Finasteride

In the 404 patients who had both ED and BPH at baseline, changes in erectile function were assessed as key secondary endpoints using the EF domain of the IIEF questionnaire. Tadalafil with finasteride (N=203) was compared to placebo with finasteride (N=201). A statistically significant improvement from baseline (tadalafil/finasteride 13.7, placebo/finasteride 15.1) was observed at week 4 (tadalafil/finasteride 3.7, placebo/finasteride -1.1; p<.001), week 12 (tadalafil/finasteride 4.7, placebo/finasteride 0.6; p<.001), and week 26 (tadalafil/finasteride 4.7, placebo/finasteride 0; p<.001).