The safety and efficacy of CAVERJECT Sterile Powder was investigated
in men with a diagnosis of erectile dysfunction due to psychogenic, vasculogenic,
neurogenic, and/or mixed etiology in two well-controlled studies (Study
1 and Study 2) and in one 6-month open-label study (Study 3).
Study 1: One hundred fifty-three men with a mean age of 53 years (range
23-69 years) were enrolled. The study had three phases: a 2.5 week double-blind,
in-office randomized crossover phase in which each man received placebo
or 2.5 mcg,
5 mcg, 7.5 mcg, or 10 mcg of CAVERJECT Sterile Powder; a 2 week open-label,
in-office dose-titration phase to identify the optimum home-use dose (the
latter dose was defined as a dose inducing an erection sufficient for penetration
and lasting
≤ 60 minutes); and a 4-week open-label, self-injection phase. In the double-blind
phase, each dose of CAVERJECT was significantly more effective than placebo
by clinical evaluation ("full penile rigidity") and by RigiScan criteria
(≥ 70% rigidity for at least 10 minutes); there was no response to placebo.
The percentage of responders increased with increasing doses of CAVERJECT.
The overall response in the dose-ranging phases was 76% (117/153) by clinical
evaluation and 51% (78/152) by RigiScan criteria. The optimum dose for self-injection
ranged from 1.25 to 65 mcg (median 20 mcg). Seventy-three percent of the
injections in 102 men who self-injected CAVERJECT resulted in satisfactory
intercourse. Seventy-five percent of the patients remained on the dose identified
during the dose-ranging phase; 17% and 8% of the patients slightly decreased
or increased the dose, respectively. The mean duration of erection per injection
was 70.8 minutes.
Study 2: Two hundred ninety-six men with a mean age of 53.8 years (range
21-74 years) were enrolled in this parallel-design, double-blind study.
The men were randomly assigned to one of five groups and received either
a single dose of placebo, 2.5 mcg, 5 mcg, 10 mcg, or 20 mcg of CAVERJECT
Sterile Powder. No patient responded to placebo. The differences in the
response rates in both the clinical and the RigiScan evaluations between
each of the doses of CAVERJECT and placebo were statistically significant.
There was also a statistically significant dose-response relationship with
higher clinical response rates and higher RigiScan response rates with increasing
doses of CAVERJECT (with exception of the 10-mcg dose). The mean duration
of erection after injection ranged from 12 minutes after the 2.5-mcg dose
to 44 minutes after the 20-mcg dose and the relationship was linear
(p = .025, linear regression analysis).
Study 3: The safety and efficacy of CAVERJECT Sterile Powder was evaluated
in a 6-month, open-label study in 683 men with a mean age of 58 years (range
20-79 years). The optimum dose of CAVERJECT was established by titration
in 89% of men (606/683). Four hundred seventy-one men (69%) completed the
6-month study. At the start of the study, the mean dose was 17.7 mcg of
CAVERJECT and at the end of the study it was 20.7 mcg. Eighty-seven percent
of the 13,762 injections of CAVERJECT, administered by self-injection by
the men in the study, resulted in satisfactory sexual activity. The mean
duration of erection was 67.5 minutes.
The formulation of alprostadil contained in CAVERJECT IMPULSE includes
the inactive excipient alpha cyclodextrin. This formulation was compared
with CAVERJECT Sterile Powder in 87 men in a single-blind, crossover study
designed to evaluate efficacy and safety. The doses used by the patients
in the study ranged from 2.5 mcg to 20 mcg and were the same for both formulations.
The efficacy of the two formulations was shown to be comparable, as assessed
by the 30-point erectile function (EF) domain score from the International
Index of Erectile Function (IIEF) and by a physician-assessment score for
erectile response. The mean EF domain scores for CAVERJECT Sterile Powder
and the formulation contained in CAVERJECT IMPULSE were 26.6 (SD=5.3) and
27.6 (SD=3.8), respectively. The mean physician's assessment scores for
CAVERJECT Sterile Powder and the formulation contained in CAVERJECT IMPULSE
were 2.6 (SD=0.6) and 2.7 (SD=0.5), respectively, based on a scale of 0
(no tumescence) to 3 (full rigidity).
