Background and Preliminary Data
The treatment of prostate cancer results in several known sexual dysfunctions/risks,
including erectile dysfunction, orgasmic dysfunction, ejaculatory dysfunction, penile
curvature (Peyronie's disease), and reduced penile length. Although all forms of prostate
cancer treatment are associated with many of these changes, prostatectomy currently has
the most data available on sexual function outcomes. Among the dysfunctions, erectile
dysfunction has remained a very challenging adverse effect without effective preventative
therapies. Specifically, prior randomized controlled trials evaluating the efficacy of
PDE5 inhibitors (vardenafil and tadalafil) have failed to demonstrate improved erectile
function preservation post-operatively.
Recently, out team conducted a single-center randomized, controlled trial evaluating the
efficacy of a novel penile traction therapy (PTT) device, RestoreX at preventing penile
length loss post-prostatectomy. In addition to meeting the primary outcome of achieving
improved penile length compared to controls, the study unexpectedly demonstrated
improvements in erectile function in the treatment group compared to controls. Results
were also consistent with two other prior randomized, controlled trials, one of which
demonstrated improved erectile function in men with Peyronie's Disease and the other in
men with diabetes mellitus (unpublished).
As these findings represent the first known therapy which resulted in preserved erectile
function post-prostatectomy, we sought to perform a larger, multi-center study in an
attempt to confirm or refute findings.
Investigational Device
RestoreX is a PTT device developed by PathRight Medical using technology licensed from
the Mayo Clinic. The device is classified as class I (orthotic) and does not require
clinical trials to prove safety or efficacy. Mayo Clinic has previously performed 3
randomized controlled trials which have confirmed the safety of the device as well as
efficacy in improving erectile function and penile length in various cohorts of men.
The device has two functional aspects. The first is the ability to provide direct
traction on the penis. The second is the ability to provide counter-bending forces, to
treat conditions such as Peyronie's disease (bent penis). In the current study, only the
direct traction aspects of the device will be utilized.
Study Rationale
PTT with Restorex has been shown to improve erectile function in several clinical
scenarios, including in men with Peyronie's disease, men with diabetes mellitus
(unpublished), and post-prostatectomy. As no therapy has ever been shown to improve
erectile function or prevent loss of erectile function post-prostatectomy, we felt that
there was significant clinical value in performing a large, multi-center, randomized,
controlled trial to affirm or refute the efficacy of Restorex PTT in preserving erectile
function post-prostatectomy.
Potential Benefits
There are several anticipated benefits to using PTT following prostatectomy. As loss of
penile length results in several issues including loss of sexual function, cosmetic
concerns, and difficulty in maintaining hygiene (incontinence resulting in yeast
infections), the ability to maintain or restore length post-prostatectomy may mitigate
these issues. Our team has previously demonstrated that Restorex PTT significantly
improved penile length post-prostatectomy. Although this is an anticipated beneficial
effect of therapy, we will not be specifically evaluating this outcome in the current
study.
In addition to improved penile length, our prior investigations have demonstrated
preserved erectile function in men who received PTT with Restorex post-prostatectomy
compared to controls. And among all patients in the three prior randomized, controlled
trials evaluating Restorex, no significant or long-term adverse events were reported,
highlighting the safety of the therapy.
Anticipated Duration of the Clinical Investigation
The overall study will be scheduled for 3 years, to permit adequate time for enrollment
and follow-up. The intervention phase will include 5 months of randomized treatment (for
the treatment arm), and 3 months of open label treatment (for all arms).