Combodart (dutasteride+tamsulosin) for benign prostatic hyperplasia
Combodart is a combination tablet containing an alpha-blocker (tamsulosin) and an alpha-reductase inhibitor (dutasteride). It is indicated for treatment of moderate to severe symptoms of benign prostatic hyperplasia (BPH). In patients with enlarged prostate, a marginally better symptomatic effect was seen for the combination tablet compared to its two active substances in monotherapy.
The largest advantage to combining dutasteride and tamsulosin appears to be the fact that an immediate symptomatic effect is achieved. This is due to the immediate effect of the alpha-blocker, whereas the full effect of the alpha-reductase inhibitor is first achieved after 9-12 months. The largest disadvantage is a significantly increased number of side effects, where erectile dysfunction is the most common. In addition, there is a markedly greater risk of “Floppy Iris Syndrome” when using tamsulosin, compared to other alpha-blockers.
The effect of Combodart has not been proven better than other combinations of alpha-blockers (alfuzosine, doxazosin) and alpha-reductase inhibitors (finasteride), but is 2-4 times more expensive. This should be considered up against a possible compliance-related advantage of taking one tablet instead of two.
The opinion of IRF: The combination therapy should be limited to patients with enlarged prostate who do not achieve a sufficient symptom relief by monotherapy. When this is the case, a combination of finasteride and doxazosin is, at the moment, the most rational choice when considering effect, side effects, price and compliance. The symptomatic effect should be re-evaluated continuously, and a change over to monotherapy with an alpha-reductase inhibitor could be considered after 9-12 months.
Combodart was marketed on June 14th, 2010.
The Institute for Rational Pharmacotherapy, September 1st, 2010.