© The Canadian Journal of Urology™; 19(Supplement 1); October 2012
Address correspondence to Dr. Jack Barkin, Department of
Surgery, University of Toronto, 404-960 Lawrence Avenue
West, Toronto, Ontario M6A 3B5 Canada
Emerging therapies: what’s new is old and
what’s old is new
Jack Barkin, MD,
1
Christine Folia, PharmD
2
1
Department of Surgery, University of Toronto, Humber River Regional Hospital, Toronto, Ontario Canada
2
Agro Health Associates In., Burlington, Ontario, Canada
BARKIN J, FOLIA C. Emerging therapies: what’s
new is old and what’s old is new.
Can J Urol
2012;19
(
Suppl 1):49-53.
Researchers are constantly seeking ways to improve
existing drugs, drug mechanisms of activity, find new
indications for old drugs or to develop new drugs to treat
urological diseases and conditions. In Canada, tadalafil in
a 5 mg daily dosage (old drug), and a new drug, silodosin,
have recently become available to treat patients who have
benign prostatic hyperplasia (BPH) with lower urinary
tract symptoms (LUTS). In clinical studies, silodosin has
shown promise as a treatment for ureteral stones, whereas
it has shown conflicting results as a potential treatment
for prostatitis. Two new therapies have emerged for
treating overactive bladder (OAB): Mirabegron (not yet
available in Canada) and fesoterodine (newly introduced
in the marketplace). New therapies—denosumab (to
prevent skeletal events) and abiraterone acetate and
enzalutamide—were recently approved to treat certain
patients with advanced prostate cancer. With the advent
of new therapies to treat urological diseases, in many
cases, primary management of the patient is often shifted
from the urologist to the family physician, and sometimes
moved from the oncologist to the urologist.
KeyWords:
indications, ED/LUTS, silodosin, cialis,
abiraterone, denosumab, enzalutamide, fesoterodine
these drugs were being tested as a potential treatment
for angina. However, it became evident that they were
more effective for treating erectile dysfunction (ED), and
that is their current approved primary indication.
1,2
The
evolution of the use of this class of drugs did not stop
here. As predicted
1
and reported
3
elsewhere, one of the
PDE-5 inhibitors (daily tadalafil) has nowbeen approved
for men with ED and lower urinary tract symptoms
(
LUTS). However, first-line therapy for men with small
prostates and LUTS remains an alpha blocker.
4
The current article reviews some of the published
data about new drugs for old conditions and new, non-
approved (but trial-suggested) uses for older approved
drugs.
Introduction
In the evolution of drug development there are often
surprises where an investigator might serendipitously
discover that the indication a drug is primarily being
tested for will not be the therapeutic area for which
the drug will ultimately be determined to be most
effective. A very good example is in the development
of phosphodiesterase-type 5 (PDE-5) inhibitors. Initially,
becauseof theirknownimpactonnitricoxidemetabolism,
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