MacroChem Corporation announced today that it is closing enrollment of new patients into a pivotal phase 3 trial for Topiglan®, the company's topical gel that may enable tens of millions of men who cannot or will not take Viagra® on option for the treatment of erectile dysfunction ("ED").
Planned as a trial of about 400 patients, the MacroChem study attracted
more than 700 couples to 30 academic and private clinics nationwide. More than
500 couples will have passed the stringent qualifications necessary to assure
the degree of the man's disorder and the partner's willingness to cooperate
with the protocol reporting requirements. Each study participant was required
to have an inability to routinely obtain intercourse-competent erections
before being given either a placebo or drug-containing gel for the balance of
"We believe that the success in recruiting so many patients from excellent
U.S. centers around the U.S. demonstrates the inherent attractiveness of
Topiglan as an alternative to oral ED drugs, and the recruitment expertise of
our clinical trial specialists, Gretchen Taintor and Judith Whitman," noted
Paul Schechter, MD, PhD, vice president of drug development and regulatory
affairs at MacroChem.
"We're optimistic that many patients who complete this trial will elect to
enroll in our open-label extension, where patients may receive up to six
months of free Topiglan doses," he said.
Topligen is a gel that is rubbed on penis just before intercourse.
It is different from Viagra and all the investigational drugs for
erectile dysfunction currently in Phase 3 - the last phase of drug development
before FDA review -- because it's not a tablet or capsule -- it's a gel
applied to the glans of the penis immediately before intercourse.
The active ingredient in the gel is alprostadil, a synthetic version of a hormone-like substance proven to safely induce erection when injected into the penis or inserted as a suppository deep into the urethra with a catheter. The gel also contains SEPA®, MacroChem's patented drug-absorption-enhancing excipient. Phase 2 trials suggest that SEPA will take alprostadil through the skin and into the penile arteries that engorge the penis with blood when a man is sexually stimulated.
Last month, Vidyya brought you news of the successful second phase of the drug's study from the the peer-review journal Urology. The results detailed the phase 2 office-based trial of Topiglan® among patients with moderate to severe erectile dysfunction, including many who had been unsuccessfully using Viagra®. In that population of difficult patients, Topiglan was almost six times more effective in inducing erections judged intercourse competent than placebo.
The active ingredient in Topiglan -- alprostadil -- differs from the
active ingredient in Viagra and other Viagra-class investigational drugs in
that it is delivered only to the penis, and appears to exert all of its
effects there. Even when injected into the penis, alprostadil is not
associated with headaches, disturbed vision, or other side effects reported
with Viagra and investigational Viagra-class drugs.
And most important for the more than 6 million American men with angina,
and millions more who have serious heart disease but don't know it,
alprostadil doesn't interact with the nitrate drugs they must carry in case
they experience exertional chest pains, or to which they might be exposed if
they should experience a heart attack. A joint committee of the American Heart
Association and the American College of Cardiology -- the nation's two leading
heart-disease medical societies -- has issued a consensus document stipulating
that patients taking or at risk of taking these heart drugs should never take