FAQs
Efficacy
- How is RAPAFLO® different from other alpha-blockers?
- How fast does RAPAFLO® relieve symptoms?
- Does RAPAFLO® work on all BPH symptoms?
- Will RAPAFLO® work in my older BPH patients (>65 years)?
- Can RAPAFLO® work in patients with larger prostates?
- Does the symptom relief last?
Safety
- Can RAPAFLO® be used safely with other antihypertensive agents?
- Can RAPAFLO® be used safely with PDE5 inhibitors?
- What are the most common side effects of RAPAFLO®?
Dosing
- How is RAPAFLO® dosed?
- Does the dose need to be adjusted in patients with renal or hepatic impairment?
Answers for Efficacy Questions
How is RAPAFLO® different from other alpha-blockers?
RAPAFLO® has a unique selectivity profile, which is reflected in its excellent clinical
profile. RAPAFLO® has a high affinity for α1A
receptors of the prostate, urethra, and bladder neck and base, which control smooth
muscle contraction in these tissues, and a relatively low affinity for α1B
receptors of the vasculature.9 In addition, RAPAFLO®
is highly tissue selective and its concentration in the prostate tissue is 200-fold
that in the aorta.27 RAPAFLO® provides rapid relief
of urine flow obstruction and BPH symptoms that is thought to be due to its high
affinity for the receptors that control these processes, and is associated with
a low incidence of orthostatic and vasodiliatory effects due to its very low affinity
for the alpha-adrenergic receptors that control vasodilation. In addition, RAPAFLO®
has only a moderate affinity for α1D receptors.
These receptors may play a role in bladder overactivity via mechanisms outside the
bladder as well as in smooth muscle contraction in the nasal cavity.26,28 Click here to see a
video of how RAPAFLO® works
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How fast does RAPAFLO® relieve symptoms?
In clinical trials, RAPAFLO® improved urine flow rate within 2 to 6 hours2,3 of taking the first dose and started relieving irritative and obstructive BPH symptoms starting within just 3 to 4 days.3
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Does RAPAFLO® work on all BPH symptoms?
RAPAFLO® has a significant impact on both obstructive and irritative BPH symptoms.
In two large randomized clinical trials involving more than 900 patients, RAPAFLO®
therapy resulted in significant reductions not only in the total IPSS score but
also on the Irritative and Obstructive Symptom subscores.3 Patients experienced significant reductions in IPSS irritative
and obstructive subscores starting within 3 to 4 days3, and these reductions were sustained throughout the Phase 3 studies.3,10
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Will RAPAFLO® work in my older BPH patients (>65 years)?
Of the patients treated with RAPAFLO® in the two pivotal clinical trials, 207 (44.4%)
were >65 years of age, and 60 (12.9%) were >75 years of age.2
Significant IPSS reductions versus baseline were observed in both younger and older
patients. There were no clinically meaningful differences with respect to IPSS reductions
or Qmax increases between patients <65 years and >65 years or between those <75
years and >75 years in controlled clinical trials.9
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Can RAPAFLO® work in patients with larger prostates?
Prostate size does not necessarily correlate with the severity of BPH symptoms. In clinical trials of RAPAFLO®, the baseline IPSS scores were 21.2 and 21.5. In fact, in patients whose baseline IPSS was ≥20 the IPSS reductions were even greater than those seen in the overall study population (-7.8 vs -6.4).2
In addition, in a post-hoc analysis of clinical trial data, RAPAFLO® was shown to
provide significant improvements in symptoms, regardless of prostate volume.9
In this analysis, prostate volume was estimated based on
PSA concentration. Patients with prostate volume ≥30 mL (n = 350) had numerically
greater reductions in IPSS than those with smaller prostates (n = 100), but this
difference was not statistically significant.9
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Does the symptom relief last?
In clinical trials, RAPAFLO® therapy resulted in significant IPSS reductions at
each time point studied—day 3-4, day 7, day 14, day 28, and day 84,9 demonstrating
its rapid onset and sustained efficacy. So, RAPAFLO® provided rapid and sustained relief of BPH symptoms.
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Answers for Safety Questions
Can RAPAFLO® be used safely with other antihypertensive agents?
In clinical trials of RAPAFLO®, approximately one-third of patients were on concomitant
antihypertensive medications,2* including ACE inhibitors, calcium channel
blockers, ARBs, and beta-blockers. (The use of other alpha-blockers was not permitted
in the study protocol). Patients taking concomitant antihypertensive medications
with RAPAFLO® did not experience a significant increase in the incidence of syncope,
dizziness, or orthostasis.2 RAPAFLO®, a uniquely selective
alpha-blocker, is associated with a low rate of orthostatic hypotension and dizziness.
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Can RAPAFLO® be used safely with PDE5 inhibitors?
In a study in 24 healthy subjects aged 45 to 78 years who were taking RAPAFLO® with
tadalafil or sildenafil at maximum doses, there were no events of symptomatic orthostasis
or dizziness. Patients taking RAPAFLO® with a single maximum dose of sildenafil (Viagra® 100 mg)
or tadalafil (Cialis® 20 mg) did not experience any clinically meaningful
decreases in blood pressure.2,21*
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What are the most common side effects of RAPAFLO®?
The most common treatment-emergent adverse event was retrograde ejaculation (28.1%), which
led to discontinuation in 2.8% of patients.2 Other
adverse events occurring in >2% of patients included dizziness (3.2%), orthostatic
hypotension (2.6%), diarrhea (2.6%), nasopharyngitis (2.4%), headache (2.4%), and
nasal congestion (2.1%).2
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Answers for Dosing Questions
How is RAPAFLO® dosed?
The recommended dose of RAPAFLO® is 8 mg orally once daily with a meal.2
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Does the dose need to be adjusted in patients with renal or hepatic impairment?
No dosage adjustment is required in patients with mild renal impairment (CCr 50-80 mL/min) or mild or moderate hepatic impairment.2
In patients with moderate renal impairment (CCr 30-50 mL/min), the dose should be reduced to 4 mg once daily.2
RAPAFLO® is contraindicated in patients with severe hepatic or renal impairment.2
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- Fenter TC, Naslund MJ, Shah MB, et al. The cost of treating the 10 most prevalent diseases in men 50 years of age or older. Am J Manag Care. 2006;12(4 suppl):S90-S98.
- RAPAFLO® (silodosin) Capsules full Prescribing Information, November 2009.
- Marks LS, Gittelman MC, Hill LA, Volinn W, Hoel G. Rapid efficacy of the highly selective α1A-adrenoceptor antagonist silodosin in men with signs and symptoms of benign prostatic hyperplasia: pooled results of 2 phase 3 studies. J Urol. 2009;181:2634-2640.
- National Institute of Diabetes and Digestive and Kidney Diseases. Prostate enlargement: benign prostatic hyperplasia. NIH Publication No. 07-3012. June 2006.
- Bruskewitz RC. Quality of life and sexual function in patients with benign prostatic hyperplasia. Rev Urol. 2003;5:72-80.
- Roberts RO, Jacobsen SJ, Rhodes T, et al. Natural history of prostatism: impaired health status in men with lower urinary tract symptoms. J Urol. 1997;157:1711-1717.
- http://www.dictionary.com
- Atlas of Human Anatomy, Frank H. Netter, MD, Ciba-Geigy Corporation, Summit, NJ, 1989.
- Data on file, Watson Laboratories, Inc.
- Marks LS, Gittelman MC, Hill LA, Volinn W, Hoel G. Silodosin in the treatment of the signs and symptoms of benign prostatic hyperplasia: a 9-month, open-label extension study. Urology. 2009;74:1318-1322.
- Agency for Healthcare Quality and Research (U.S. Dept Health and Human Services): Quick Tips When Talking With Your Doctor. Available at: http://www.ahrq.gov/consumer/quicktips/doctalk.htm. Accessed July 28, 2010.
- American Urological Association. AUA guideline on management of benign prostatic hyperplasia (2003). Chapter 1: Diagnosis and treatment recommendations. J Urol. 2003;170:530-547.
- Fagelman E, Lowe FC. Herbal medications in the treatment of benign prostatic hyperplasia (BPH). Urol Clin N Am. 2002;29:23-29, vii.
- National Institute on Aging: Talking With Your Doctor: A Guide For Older People. NIH Publication No. 05-3452. August 2005 (Reprinted April 2010). Available at: http://www.nia.nih.gov/NR/rdonlyres/90DF996C-DF5F-4245-B7CA-B2E1B993D8C7/0/TWYD_0521_web.pdf. Accessed July 29, 2010.
- Medline Plus Medical Encyclopedia from NIH: Enlarged Prostate. Available at: http://www.nlm.nih.gov/medlineplus/ency/article/000381.htm. Accessed July 29, 2010.
- Shvartzman P, Borkan JM, Stoliar L, et al. Second-hand prostatism: effects of prostatic symptoms on spouses’ quality of life, daily routines and family relationships. Family Pract. 2001;18:610-613.
- Kuritzky L. A primary care physician’s perspective on benign prostatic hyperplasia. Rev Urol. 2003;5(suppl 5):S42-S48.
- Wolters R, et al: Lower urinary tract symptoms: social influence is more important than symptoms in seeking medical care. BJU Int. 2002;90:655–661.
- Rosen RC, Giuliano F, Cason CC. Sexual dysfunction and lower urinary tract symptoms (LUTS) associated with benign prostatic hyperplasia (BPH). Eur Urol. 2005;47:824–837.
- Ponholzer A, Madersbacher S. Lower urinary tract symptoms and erectile dysfunction; links for diagnosis, management and treatment. Int J Impot Res. 2007;19:544-550.
- MacDiarmid SA, Hill LA, Volinn W, Hoel G. Lack of pharmacodynamic interaction of silodosin, a highly selective α1a-adrenoceptor antagonist, with the phosphodiesterase-5 inhibitors sildenafil and tadalafil in healthy men. Urology. 2010;75:520-525.
- Marks LS. Reply to editorial comment. Urology. 2009;74:1323-1324.
- Schwinn DA, Roehrborn CG. α1-Adrenoceptor subtypes and lower urinary tract symptoms. Int J Urol. 2008;15:193-199.
- Straus SM, Kors JA, De Bruin ML, et al. Prolonged QTc interval and risk of sudden cardiac death in a population of older adults. J Am Coll Cardiol. 2006;47:362-367.
- Carbone DJ, Hodges S. Medical therapy for benign prostatic hyperplasia: sexual dysfunction and impact on quality of life. Int J Impot Res. 2003;15:299-306.
- Nomiya M, Yamaguchi O. A quantitative analysis of mRNA expression of alpha 1 and beta-adrenoceptor subtypes and their functional roles in human normal and obstructed bladders. J Urol. 2003;170(2 Pt 1):649-653.
- Murata S, Taniguchi T, Takahashi M, et al. Tissue selectivity of KMD-3213, an α1-adrenoreceptor antagonist, in human prostate and vasculature. J Urol. 2000;164:578-583.
- Stafford-Smith M, Bartz R, Wilson K, et al. Alpha-adrenergic mRNA subtype expression in the human nasal turbinate. Can J Anesth. 2007;54:549-555.
- Wei JT, Calhoun E, Jacobsen SJ. Urologic Diseases in America Project: benign prostatic hyperplasia. J Urol. 2008;179(5 Suppl.):S75-S80.
- Issa MM, Regan T. Medical therapy for benign prostatic hyperplasia—present and future impact. Am J Manag Care. 2007;13:S4-S9.
- Berry SJ, Coffey DS, Walsh PC, et al. The development of human benign prostatic hyperplasia with age. J Urol. 1984;132:474.
- Nickel JC. Comparison of clinical trials with finasteride and dutasteride. Rev Urol. 2004;6 Suppl 9:S31-39.
- Hernández C, Estivill E, Prieto M, et al. Nocturia in Spanish patients with lower urinary tract symptoms suggestive of benign prostatic hyperplasia (LUTS/BPH). Curr Med Res Opin. 2008;24:1033-1038.
RAPAFLO® is indicated for the treatment of the signs and symptoms of benign prostatic hyperplasia (BPH). RAPAFLO® is not indicated for the treatment of hypertension.
RAPAFLO® is contraindicated in patients with severe renal impairment (CCr <30 mL/min), severe hepatic impairment (Child-Pugh score ≥10), and with use of strong CYP3A4 inhibitors. Postural hypotension with or without symptoms (eg, dizziness) may develop when beginning treatment with RAPAFLO®. As with all alpha-blockers, there is a potential for syncope. Patients should be warned of the possible occurrences of such events and should avoid situations where injury could result. RAPAFLO® should be used with caution in patients with moderate renal impairment. Patients should be assessed to rule out the presence of prostate cancer prior to starting treatment with RAPAFLO®. Patients planning cataract surgery should inform their ophthalmologist that they are taking RAPAFLO®.
The most common side effects are retrograde ejaculation, dizziness, diarrhea, orthostatic hypotension, headache, nasopharyngitis, and nasal congestion.
