Efficacy of once-a-day terazosin in benign prostatic hyperplasia: a randomized, double-blind placebo-controlled clinical trial

Scoping Review of Randomized Trials With Discontinuation of Medicines in Older Adults

OBJECTIVES

To map the randomized trial evidence describing the feasibility of discontinuing active medications with potential adverse effects in older patients.

DESIGN

Scoping review with systematic search of PubMed, Embase, and Cochrane Library.

SETTING AND PARTICIPANTS

Randomized trials investigating discontinuation of a single medicine or medicine class in patients with mean age ≥65 years.

METHODS

We extracted trial characteristics including study design and assessed bias. As proxies for the "feasibility of discontinuation," we extracted the "dropout rate" and "disease recurrence rate."

RESULTS

We identified 40 trials investigating discontinuation of symptomatic (n = 26), preventive (n = 6), or both preventive and symptomatic medicines (n = 8) against psychiatric (n = 10), neurologic (n = 9), musculoskeletal (n = 8), cardiovascular (n = 5), respiratory (n = 4), and urologic diseases (n = 4). Five discontinuation designs were used, 75% (30/40) of trials were placebo-controlled, and 48% (19/40) of trials had bias disfavoring discontinuation. The dropout rate was similar between the discontinuation group and the continuation group in 79% of the trials (30/38), whereas disease recurrence was similar in 72% (23/32) of the trials. In 42% (13/31) of trials reporting both dropout rate and disease recurrence rate, the differences between groups were statistically insignificant and less than 10%; these trials investigated discontinuation of cholinesterase inhibitors for Alzheimer's disease in various settings (n = 3), alendronate for osteoporosis (n = 3), glucosamine for osteoarthritis, lithium as adjunct for unipolar depression, statins for cardiovascular disease in patients with limited life expectancy, droxidopa for neurogenic orthostatic hypotension, tamsulosin for lower urinary tract symptoms, sertraline for major depressive episode, and fentanyl patch for low back or osteoarthritis pain.

CONCLUSIONS AND IMPLICATIONS

We identified 40 randomized trials using a variety of designs investigating discontinuation of both symptomatic and preventive medicines in older patients. Discontinuation of medicines seems feasible for most of the investigated medicines. This scoping review can guide clinical practice and future trials on deprescribing.

Discontinuation of alpha-blocker therapy in men with lower urinary tract symptoms: a systematic review and meta-analysis

OBJECTIVES

We aimed to synthesise the available data for the effect of stopping alpha-blocker therapy among men with lower urinary tract symptoms. The focus was on symptom, uroflowmetry and quality of life outcomes, but we also reviewed the adverse events (AEs) and the number of patients who restarted therapy.

DATA SOURCES

We searched MEDLINE/PubMed, EMBASE/Ovid and The Cochrane Central Register of Controlled Trials from inception to May 2018.

ELIGIBILITY CRITERIA

We selected studies regardless of study design in which men were treated with an alpha-blocker for at least 3 months and in which the effects of alpha-blocker discontinuation were subsequently studied. Only controlled trials were used for the primary objective.

DATA EXTRACTION AND SYNTHESIS

Two reviewers independently extracted data and assessed the risk of bias for the controlled studies only using the Cochrane Collaboration's tool for assessing risk of bias. Data were pooled using random-effects meta-analyses.

RESULTS

We identified 10 studies (1081 participants) assessing the primary objective. Six studies (733 participants) assessed differences in AEs between continuation and discontinuation, and six studies (501 participants) reported the numbers of subjects that restarted treatment after discontinuation. No studies in primary care were identified. After discontinuing monotherapy, symptom scores increased and peak flow rates decreased at 3 and 6 months, but not at 12 months; however, neither parameter changed when alpha-blockers were stopped during combination therapy. Small differences in post-void residual volumes and quality of life scores were considered clinically irrelevant. We also found that 0%-49% of patients restarted after stopping alpha-blocker therapy and that AEs did not increase with discontinuation.

CONCLUSIONS

Discontinuing alpha-blocker monotherapy leads to a worsening compared with continuing therapy. Discontinuing the alpha-blocker after combination therapy had no significant effects on outcomes in either the short or long term. Discontinuation may be appropriate for the frail, elderly or those with concomitant illness or polypharmacy. However, studies in primary care are lacking.

PROSPERO REGISTRATION NUMBER

CRD42016032648.

Nocturia: The circadian voiding disorder

Nocturia is a prevalent condition of waking to void during the night. The concept of nocturia has evolved from being a symptomatic aspect of disease associated with the prostate or bladder to a form of lower urinary tract disorder. However, recent advances in circadian biology and sleep science suggest that it might be important to consider nocturia as a form of circadian dysfunction. In the current review, nocturia is reexamined with an introduction to sleep disorders and recent findings in circadian biology in an attempt to highlight the importance of rediscovering nocturia as a problem of chronobiology.

ZnO/rGO nanocomposite/carbon paste electrode for determination of terazosin in human serum samples

Terazosin (TR) is used for the treatment of symptoms of an enlarged prostate.

Comparative effectiveness of oral drug therapies for lower urinary tract symptoms due to benign prostatic hyperplasia: a systematic review and network meta-analysis

INTRODUCTION

Lower urinary tract symptoms (LUTS) due to benign prostatic hyperplasia (BPH) are common in elder men and a number of drugs alone or combined are clinically used for this disorder. But available studies investigating the comparative effects of different drug therapies are limited. This study was aimed to compare the efficacy of different drug therapies for LUTS/BPH with network meta-analysis.

MATERIALS AND METHODS

An electronic search of PubMed, Cochrane Library and Embase was performed to identify randomized controlled trials (RCTs) comparing different drug therapies for LUTS/BPH within 24 weeks. Comparative effects were calculated using Aggregate Data Drug Information System. Consistency models of network meta-analysis were created and cumulative probability was used to rank different therapies.

RESULTS

A total 66 RCTs covering seven different therapies with 29384 participants were included. We found that α-blockers (ABs) plus phosphodiesterase 5 inhibitors (PDE5-Is) ranked highest in the test of IPSS total score, storage subscore and voiding subscore. The combination therapy of ABs plus 5α-reductase inhibitors was the best for increasing maximum urinary flow rate (Qmax) with a mean difference (MD) of 1.98 (95% CI, 1.12 to 2.86) as compared to placebo. ABs plus muscarinic receptor antagonists (MRAs) ranked secondly on the reduction of IPSS storage subscore, although monotherapies including MRAs showed no effect on this aspect. Additionally, PDE5-Is alone showed great effectiveness for LUTS/BPH except Qmax.

CONCLUSIONS

Based on our novel findings, combination therapy, especially ABs plus PDE5-Is, is recommended for short-term treatment for LUTS/BPH. There was also evidence that PDE5-Is used alone was efficacious except on Qmax. Additionally, it should be cautious when using MRAs. However, further clinical studies are required for longer duration which considers more treatment outcomes such as disease progression, as well as basic research investigating mechanisms involving PDE5-Is and other pharmacologic agents alleviate the symptoms of LUTS/BPH.

Changes in peak urinary flow and voiding efficiency in men with signs and symptoms of benign prostatic hyperplasia during once daily tadalafil treatment

OBJECTIVE

To determine, by post hoc analysis, the effects of tadalafil (a long-acting phosphodiesterase 5 inhibitor) on peak urinary flow (Q(max)), bladder capacity, voiding efficiency and the obstructive symptoms of benign prostatic hyperplasia (BPH) in men with lower urinary tract symptoms secondary to BPH (BPH-LUTS), compared with placebo.

PATIENTS AND METHODS

After a 4-week placebo run-in period, 1058 men with BPH-LUTS were randomly allocated to receive once daily treatment with placebo or tadalafil (2.5, 5, 10, or 20 mg) for 12 weeks. Uroflowmetry, postvoid residual volume (PVR), and BPH symptom score measurements were assessed throughout the trial.

RESULTS

Increases in Q(max) were numerically greater for tadalafil (2.5, 5, 10, and 20 mg with percentage changes of 15%, 16%, 17%, 22%, respectively) vs placebo (12%), but did not reach statistical significance. Age, baseline Q(max), erectile dysfunction history, sexual activity, and previous alpha-blocker therapy significantly influenced the Q(max) response. Tadalafil was not associated with significant changes in PVR. Tadalafil had its greatest effects on bladder capacity and voiding efficiency in men with a Q(max) of <10 mL/s at baseline, but these changes were not significantly different from placebo responses. Tadalafil treatment significantly improved the IPSS obstructive subscores (tadalafil 2.5, 5, 10, 20 mg with percentage changes of 24%, 31%, 33%, 33%, respectively) vs placebo (13%).

CONCLUSIONS

Once daily tadalafil did not significantly change Q(max) or voiding efficiency compared with placebo in men with BPH-LUTS, although there were dose-dependent improvements. No subgroups were identified where tadalafil or placebo treatment had a deleterious effect on Q(max). Despite these minimal changes in uroflowmetric measures, tadalafil was associated with clinically meaningful and statistically significant improvements in the obstructive symptoms of BPH.

Effects of branded versus generic terazosin hydrochloride in adults with benign prostatic hyperplasia: a randomized, open-label, crossover study in Taiwan

BACKGROUND

Terazosin is an alpha1-selective adrenoceptor blocking agent that has been reported in many clinical trials to be an effective choice for the treatment of benign prostatic hyperplasia (BPH). To improve cost-effectiveness, the development of an effective and well-tolerated generic formulation is needed.

OBJECTIVE

The aim of this study was to compare the efficacy and tolerability of branded versus generic terazosin hydrochloride in adult patients with symptomatic BPH in Taiwan.

METHODS

This randomized, open-label, 2-sequence, 2-period crossover study was conducted at the Urological Clinic, National Cheng Kung University Medical Center, Taman, Taiwan. Men newly diagnosed with symptomatic BPH who had not previously received treatment for BPH were recruited between August 2002 and April 2006. Patients were randomly assigned to 1 of 2 treatment sequences. Group A received generic terazosin during period 1 (6 weeks) and branded terazosin in period 2 (6 weeks); group B received the branded drug during period 1 and the generic during period 2. The 2 study periods were separated by a 1-week washout period. All treatments were given by mouth once daily (bedtime) at an initial dosage of 2 mg/d for the first 2 weeks. At the week-2 study visit in each treatment period, the dosage could be increased to 4 mg/d or decreased to 1 mg/d based on each patient's response and experience of adverse effects (AEs), based on the opinion of the investigator. Efficacy variables included the total score on the International Prostate Symptom Scale (IPSS), a 7-item instrument used to assess objective lower urinary tract symptoms, including quality of life. IPSS was measured at baseline and weeks 2 and 6 of each treatment period, and maximal and mean uroflow rates, measured at baseline and week 6. Tolerability was assessed at each time point using physical examination, including vital signs; laboratory analysis; and spontaneous reporting.

RESULTS

Fifty-three patients were randomized; 43 were included in the efficacy analysis (mean [SD] age, group A, 64.5 [7.7] years and group B, 62.9 [8.2] years; mean [SD] weight, group A, 66.4 [7.2] kg and group B, 67.1 [8.9] kg; all patients were Taiwanese). At 2 and 6 weeks, no significant between-product differences were found in mean (SD) decreases from baseline in IPSS total score (generic, 2.46 [0.84] and 2.46 [1.00], respectively; branded, 1.56 [0.60] and 2.87 [0.71]). At week 6, the between-product difference in mean increase from baseline in maximal uroflow rate was nonsignificant (generic, 2.36 [0.90] mL/s; branded, 2.03 [0.62] mL/s). A total of 86 treatment-emergent AEs were reported (45 with the generic drug; 41 with the branded drug), all of which were considered by the investigator as nonserious except for 1 case of acute epididymitis, which occurred with the generic drug. The most common AEs reported with the generic and branded formulations were dizziness (7/48 [14.6%] and 10/50 [20.0%], respectively) and peripheral edema (1/48 [2.1%] and 3/50 [6.0%]). No significant differences in the prevalences of AEs were found between the 2 treatments.

CONCLUSION

In this group of Taiwanese patients with symptomatic BPH, the efficacy and tolerability of generic terazosin were similar to those of branded terazosin.

Improved high-performance liquid chromatographic analysis of terazosin in human plasma

A simple, sensitive and reproducible high-performance liquid chromatography (HPLC) method was developed for the determination of terazosin in human plasma. The method involves a one-step single solvent extraction procedure using dichloromethane with a 0.25 ml plasma sample. Recovery values were all greater than 90% over the concentration range 0.25-100 ng/ml. Terazosin was found to adsorb to glass or plastic tubes, but this could be circumvented by using disposable plastic tubes. Also, rinsing the injector port with methanol after each injection helped to prevent any carry-over effect. The internal standard, prazosin, did not exhibit this problem. The method has a quantification limit of 0.25 ng/ml. The within- and between-day coefficient of variation and accuracy values were all less than 7% over the concentration range 0.25-100 ng/ml and hence the method is suitable for use in pharmacokinetic studies of terazosin.

[Prostatic benign hypertrophy: review of effectiveness, tolerance, and impact on quality of life of prolonged treatment with alfuzosin]

OBJECTIVES

To evaluate the effectiveness of Alfuzosin in terms of long term effect in BHP patients. To analyze the effectiveness according to the observer, the treatment compliance and the tolerance of alfuzosin, and specifically, cardiovascular and sexually adverse events. Also, to define the clinical profile of the BPH patients that spontaneously seek medical treatment in Spain.

DESIGN OF THE STUDY

Observational, descriptive, multicentric and 6-month retrospective study. DATA SOURCES AND COLLECTION: From the patient reports of BPH patients treated with alfuzosin during more than 6 months, data gathered were, along with usually anamnesic data and physical exploration (age, symptoms, blood pressure, e.g.), those related to treatment response, effectiveness, compliance and tolerance of Alfuzosin in the first and second quarter. Data of the 1635 patients initially recruited were considered to define the clinical profile of this population. Effectiveness and tolerance analysis were undertaken with the 911 patients who followed the treatment during the 6-month study.

RESULTS

After 6 months of treatment an improvement of the mean intensity of each of the urinary symptoms were statistically significant (p < 0.005). Also, the mean score of each of the analyzed variables and of the I-PSS global score were reduced significantly (p < 0.005). After 6 months of treatment the effectiveness evaluated by the observer was good or very good for the 88.5% of the patients. Treatment compliance was very good; from the 911 patients finishing the study, 96.4% continued with the initially prescribed treatment. Just 16 patients (3%) developed adverse events; measures undertaken were to modify the dosage or to interrupt the treatment (2 cases). The specific study of cardiovascular adverse events showed a mild reduction in the systolic (142 mmHg versus 137.86 mmHg) and diastolic blood pressure (83.53 mmHg) versus 80.72 mmHg), and the heart rate (76.80 l/m versus 76.04 l/m). The mean score of sexual life showed an improvement in all the items studied, although very slight.

CONCLUSIONS

The usefulness, effectiveness and tolerance of a long term treatment with alfuzosin in HPB patients was confirmed. Alfuzosin is considered a first choice treatment in patients with the clinical profile described.

Tamsulosin for the treatment of benign prostatic hypertrophy

OBJECTIVE

To review the information necessary to assess the efficacy and safety of tamsulosin compared with other adrenergic antagonists for treatment of symptomatic benign prostatic hyperplasia.

DATA SOURCES

A search was conducted of Cumulated Index Medicus, January 1993-August 1999, which was restricted to human trials and English-language journals.

STUDY SELECTION AND DATA EXTRACTION

Efficacy studies were included if the design was randomized and included a control group. Drug safety was assessed using data from any patient series or controlled study.

DATA SYNTHESIS

Tamsulosin, a uroselective alpha1A-adrenergic receptor antagonist, relaxes smooth muscle in the prostate and bladder neck, thereby enhancing bladder emptying. In randomized, controlled clinical trials using standardized instruments, tamsulosin improves obstructive voiding symptoms by at least 25% in 65-80% of patients with symptomatic benign prostatic hyperplasia. Tamsulosin also improves peak urinary flow rate by 1.4-3.6 mL/sec in various studies and reduces post-void residual urine volume. The usual dosage of tamsulosin was 0.4 or 0.8 mg orally once a day in the studies performed in the US and Europe; daily doses of 0.1-0.4 mg were used in studies performed in Japan. The beneficial effects of tamsulosin on voiding symptoms, peak urinary flow rate, and bladder emptying appear to be dose-related, up to a ceiling dose of 0.4 mg. The most common adverse effects are headache, asthenia, dizziness, and rhinitis-like complaints. Retrograde or delayed ejaculation occurs in 4.5-14.0% of patients and has required discontinuation of treatment in a minority of these patients. At the usual dose of 0.4-0.8 mg/d, tamsulosin does not appear to significantly reduce blood pressure, increase heart rate, or cause first-dose syncope; therefore, dosage titration is not necessary when initiating treatment. Use of nifedipine, enalapril, atenolol, furosemide, or digoxin does not require dosage modification when tamsulosin is initiated concomitantly; hypotension has not been reported with combined use of tamsulosin and these commonly used agents.

CONCLUSIONS

Tamsulosin is an improvement over other alpha-adrenergic antagonists for the management of symptoms of benign prostatic hyperplasia. It is a more convenient alternative that does not require initial dosage titration, has a fast onset of action, and has a low potential to cause hypotension when used alone or in combination with commonly used antihypertensive agents. It is more costly than some of the other second-generation alpha-adrenergic antagonists.

Terazosin in benign prostatic hyperplasia: effects on blood pressure in normotensive and hypertensive men

OBJECTIVE

To determine the effects of terazosin on blood pressure and on antihypertensive therapy when used in managing benign prostatic hyperplasia (BPH).

PATIENTS AND METHODS

Safety data from a large, multinational study were analysed retrospectively. Normotensive and hypertensive patients received escalating dosages of terazosin for 10 weeks and were maintained on 5 or 10 mg daily doses for 16 weeks (single-blind period). After the initial treatment period, only men having sufficient improvements in International Prostate Symptom Score (> or = 30%) and in peak flow rate (> or = 10%) were randomly assigned to continue terazosin or to receive placebo for 24 weeks (double-blind period).

RESULTS

In hypertensive patients, terazosin reduced systolic blood pressure (SBP) and diastolic blood pressure (DBP) during the single-blind period; these clinically significant reductions were maintained in patients receiving terazosin during the double-blind period. However, in normotensive and controlled hypertensive patients terazosin produced no clinically significant mean changes in SBP or DBP during either study period. Terazosin did not adversely affect patients receiving concomitant antihypertensive medication.

CONCLUSION

Terazosin is a safe treatment for BPH in normotensive and hypertensive men, including men who are already taking additional antihypertensive drugs.

How to select patients suitable for transurethral microwave thermotherapy: a systematic evaluation of potentially predictive variables

OBJECTIVE

To identify clinical variables useful in predicting outcome after transurethral microwave thermotherapy (TUMT) of the prostate with Prostasoft v. 2.0.

PATIENTS AND METHODS

Thirty-eight men with symptomatic benign prostatic hyperplasia (BPH) were treated with TUMT using the Prostatron device with the low-energy (v. 2.0) software. Before and 6 months after treatment symptoms were evaluated using the Madsen-Iversen (M-I) symptom score, a clinical examination and suprapubic pressure-flow measurement, free urinary peak flow rate (Qmax) and determination of post-void residual urine volume (PVR). Bladder outlet obstruction was assessed from urodynamic pressure-flow studies using the classification of Abrams and Griffiths, the obstruction grading of Schäfer, and calculation of other published factors, e.g. the urethral resistance, an obstruction index and the detrusor adjusted mean passive urethral resistance factor (DAMPF). Categories of M-I score (total, irritative and obstructive), PVR and Qmax were investigated to determine whether any could predict the outcome after low-energy TUMT. The values after treatment and changes in Qmax, M-I score and PVR were used as efficacy variables.

RESULTS

Variables describing infravesical obstruction had predictive characteristics that may be useful in selecting patients for TUMT v. 2.0 and significantly better results were obtained in patients with a low to moderate obstruction as graded using the DAMPF classification of obstruction. The results also indicated that patients with a high irritative M-I score or a Qmax of 7-14 mL/s were those who fared best after TUMT.

CONCLUSIONS

Variables expressing the obstruction grade seem to be useful in predicting outcome after TUMT (v. 2.0). Patients with a high obstruction index are probably unsuitable for TUMT (v. 2.0).

Influence of prostate size on terazosin efficacy

BACKGROUND

While the rationale for the use of alpha1-adrenoreceptor antagonists in the treatment of bladder outlet obstruction is well established, not all patients have either objective or subjective improvement. The aim of this study was to evaluate the influence of prostatic size on the changes of peak flow rate, average flow rate and residual urine in symptomatic BPH patients undergoing terazosin treatment.

METHODS

Thirty-five patients with symptomatic BPH received terazosin, 5 mg once a day for 3 weeks after a 2-week dose escalation period. Peak and average flow rates as well as residual urine were assessed before and after treatment. The patients were stratified in 3 groups by prostate size, which was estimated by transabdominal ultrasonography and a digital rectal examination.

RESULTS

The baseline characteristics for age, peak flow rate and average flow rate did not vary between the 3 groups, however, the pretreatment volume of residual urine was greater in patients with large prostate adenomas. Terazosin treatment resulted in significant changes in flow rate and residual urine, however, changes in flow rates were not influenced by prostate size, while a marked decrease in residual urine was found in patients with large prostates.

CONCLUSION

Patients treated with terazosin obtained similar improvement in peak and average uroflow, independent of the size of the prostate.

Treatment of benign prostatic hyperplasia. A pharmacoeconomic perspective

Men with moderate symptoms of benign prostatic hyperplasia (BPH) are the best candidates for medical treatment, while surgery is usually indicated for patients with severe symptoms. Men with mild symptoms do not usually need treatment, but they might be re-evaluated annually if desirable. Finasteride, which produces selective hormonal deprivation, is now established as a well tolerated drug for the long term medical therapy of BPH. Recent studies suggest that finasteride is most effective in men with large prostates (> 40 ml), and the drug should probably be reserved for these patients. alpha-Blockers work in men with small or large prostates, and their rapid onset of action facilitates the identification of responders. alpha-Blockers are more effective than finasteride during the first year of treatment, but only finasteride induces regression of the prostate and offers increased efficacy over time. Even if drug therapy reduces the need for prostate surgery, the total economic cost of BPH treatment is likely to rise because of the increasing application of medical treatment. The magnitude of this increase depends largely on what percentage of the male population embark on long term therapy, at what age treatment is started, and how successful it is. At present, the answers to these questions are largely unknown. The personal economic expenses for men who begin long term medical therapy will probably be an important factor in deciding how common drug treatment for BPH will become in the future. For many men, the main benefit of drug treatment will be the relief of urinary symptoms, but whether this improvement is substantial enough to improve their overall quality of life has not yet been clearly demonstrated in controlled studies.

A multicenter, randomized, double-blind, placebo-controlled study to evaluate the safety and efficacy of terazosin in the treatment of benign prostatic hyperplasia

OBJECTIVES

This study was designed to evaluate the safety and efficacy of the selective alpha 1-adrenoceptor blocker terazosin in the treatment of benign prostatic hyperplasia (BPH).

METHODS

Two hundred twenty-four patients aged 50 to 80 years, who had a diagnosis of BPH based on medical history, physical examination, and digital palpation, were recruited from 11 different sites between January 1992 and January 1994. The study consisted of a screening phase, a placebo phase, a double-blind dose-titration phase, and a double-blind maintenance phase.

RESULTS

Of the patients recruited, 164 entered the double-blind phase and of these 134 were evaluable. Only 11 patients withdrew because of an adverse event, 7 in the terazosin and 4 in the placebo group. Compared to placebo, terazosin significantly increased peak and mean urine flow rates without significantly affecting voided volume or postvoid residual volume. It significantly improved both the obstructive and irritative symptoms associated with BPH. Fifty-one patients from the terazosin group reported a total of 120 adverse events compared with 83 reported by 42 patients in the placebo group. The majority of these events were mild to moderate. Seventeen terazosin-treated patients reported hypotension-related adverse events and 4 withdrew from the study. However, concurrent treatment with antihypertensive agents did not affect the blood pressure response of the terazosin group.

CONCLUSIONS

Overall, this study showed terazosin to be safe and effective in relieving the signs and symptoms of BPH and should be considered as a treatment alternative.

Does anamnestic symptom evaluation or clinical examination give enough information to evaluate the severity of obstruction in benign prostatic hyperplasia?

In this study we have investigated 70 men fulfilling the usual criteria accepted for transurethral resection of the prostate (TURP). The anamnestic evaluation included the Madsen-Iversen symptom score and a quality of life questionnaire. The clinical examination included suprapubic pressure flow measurement, free urinary flow, the determination of residual urine and the ultrasound evaluation of the size of the prostate. The clinical data were correlated with the grade of obstruction according to Schäfer calculated from the pressure/flow studies. No correlation was found between the grade of obstruction and anamnestic symptom data, the size of the prostate or residual urine. A slight correlation was found between the Schäfer grade of obstruction and the flow curve pattern or peak flow.

Doxazosin--an alpha-1 receptor blocking agent in the long-term management of benign prostatic hyperplasia (Part One)

This is a controlled efficacy study with doxazosin (4 mg/day) in the long-term management of 64 ambulatory patients with benign prostatic hyperplasia (BPH). Doxazosin was given for 72 weeks and is being continued. Twenty-three controls were treated with prazosin (Minipress-4 mg/day) for 24 weeks, after which the results were similar in both the doxazosin (group 1) and prazosin (group 2) patients. Maximal and mean urethral flow increased by 44.8% and 43.5%, retention volume fell by 72.0% and 74.5%, obstructive symptoms decreased by 89.6% and 92.8% and irritation was alleviated by 81.6% and 85.0% in groups 1 and 2, respectively. Global score improved by 81.5% in group 1 and by 93.0% in group 2. Both doxazosin and prazosin produced good and similar therapeutic results. Doxazosin has the advantage of more convenient dosing (once daily) and unlike prazosin it does not produce orthostatic blood pressure falls; it is less toxic and better tolerated.

Long-term efficacy and safety of terazosin in patients with benign prostatic hyperplasia. Terazosin Research Group

OBJECTIVES

To evaluate long-term efficacy and safety of terazosin, a selective alpha 1 blocker, in the treatment of benign prostatic hyperplasia (BPH).

METHODS

This was a long-term (42 months), open-label, multicenter study with patients evaluated at 1- to 6-month intervals. Twenty-three outpatient clinics throughout the United States and Canada participated in the study. A total of 494 men with symptomatic BPH, lacking absolute indications for surgery, were enrolled in this study; 298 were transferred into the study from randomized, placebo-controlled studies of terazosin and 196 had no prior terazosin therapy. Terazosin was given starting at 1 mg/d and titrated upward until symptoms were relieved or a maximum dose of 20 mg/d was achieved, whichever came first.

RESULTS

Peak urinary flow rates at all visits were significantly higher than baseline values, with mean improvements ranging from 1.0 to 4.0 mL/s. At 3 months, 40% of patients exhibited a 30% or greater improvement in peak flow rate; this improvement was maintained through 42 months. Boyarsky symptom scores improved significantly at all visits; mean total score improved by at least 4.0 points (40%) at all visits beyond 3 months. The most common adverse events resulting in premature termination from the study were dizziness (6.7%), asthenia (3.8%), and somnolence (2.0%).

CONCLUSIONS

This study suggests that terazosin is well tolerated and effective in longterm treatment of patients with BPH.

Long-term treatment of benign prostatic hyperplasia with alfuzosin: a 24-30 month survey. BPHALF Group

OBJECTIVE

To address the long-term results of alfuzosin, an alpha 1-antagonist, in patients with benign prostatic hyperplasia (BPH).

PATIENTS AND METHODS

A 6-month, placebo-controlled study involving 518 patients was followed by two successive one-year, open extensions. Only centres who wished to continue the trial participated in the extensions; 131 patients entered the first extension, with 50 continuing into the second year extension. The results of the second year follow-up are presented here.

RESULTS

Depending on their initial randomization to either the placebo or alfuzosin arm, patients were treated with alfuzosin for 24 (n = 50) or 30 months (n = 22). The data collected on those 50 patients in comparison to baseline confirmed that the clinical efficacy observed in short/medium-term studies was maintained. A clinically significant improvement in urinary symptoms was observed; the Boyarsky score decreased from 8.7 (+/- 0.3) at baseline to 5.2 (+/- 0.3) at 24 months, with no deterioration in the objective parameters. In patients treated for 30 months (n = 22), symptomatic assessment and urodynamic parameters remained stable, indicating the sustained effectiveness of therapy. No serious or unexpected side-effect related to long-term exposure to alfuzosin was observed. No complications associated with BPH occurred. Two patients (4%) reported dizziness, neither of whom withdrew from the study. In this population, where 40% of patients were receiving concomitant cardiovascular therapy, no clinically significant change in standing systolic blood pressure, diastolic blood pressure or heart rate was apparent between baseline data and those at 24 months.

CONCLUSION

These data demonstrate the usefulness of long-term treatment with alfuzosin in patients with uncomplicated, moderate BPH.

A three month double-blind study of doxazosin as treatment for benign prostatic bladder outlet obstruction

OBJECTIVE

To evaluate the efficacy and tolerability of doxazosin in the treatment of bladder outflow obstruction resulting from benign prostatic hyperplasia (BPH).

PATIENTS AND METHODS

One-hundred and thirty-five patients with symptomatic urodynamically confirmed obstructive BPH were treated for 12 weeks with either doxazosin (67 patients) or placebo (68 patients) after an initial 2 week baseline evaluation. The main outcome measures were urodynamic and symptomatic evaluation for efficacy. Blood pressure and adverse events were monitored.

RESULTS

Data were obtained in 122 patients (60 doxazosin, 62 placebo). Doxazosin produced increases in both mean and maximum urinary flow rates of 1.01 ml/s and 3.2 ml/s respectively, compared with 0.21 ml/s and 2.2 ml/s on placebo. The increase in mean flow rate was statistically significant (P = 0.04), while that for maximum flow rate approached significance (P = 0.09). The maximum subtracted voiding pressure was substantially reduced (P = 0.007) and 19 of 53 (36%) patients had an increase in maximum flow rate of 50% or more compared with 9 of 54 (17%) on placebo (P = 0.024). Twelve weeks' therapy with doxazosin resulted in significant improvements (compared with placebo) in: hesitancy (doxazosin 26 of 46, placebo 11 of 43; P = 0.003), impaired urinary stream (doxazosin 31 of 55, placebo 16 of 48; P = 0.019) nocturia (doxazosin 22 of 56, placebo 10 of 54; P = 0.017) and urgency (doxazosin 27 of 45, placebo 16 of 42; P = 0.041). Frequency improved with doxazosin therapy (doxazosin 26 of 59, placebo 15 of 55; P = 0.062). Adverse events, most frequently dizziness and headache, were usually mild and transient and led to a discontinuation of doxazosin therapy in one patient. No clinically significant changes in sexual function or blood pressure were seen.

CONCLUSION

Doxazosin was well-tolerated and produced both urodynamic and symptomatic improvement in men with BPH, thereby providing a satisfactory alternative to existing drugs with the additional benefit of once daily dosage.

Effect of terazosin on urine storage and voiding in the aging male with prostatism

Patients in a private practice, evaluated for prostatism due to benign prostatic hypertrophy were offered the options of medical treatment with the alpha blocker terazosin, surgical treatment, or continued observation. Nineteen men accepted terazosin treatment and are the subjects of the present series. They were treated over a mean period of 8 months, the longest treatment lasting over 22 months. Dosage was started at 1 mg/d and increased as tolerated to 2, 5, and 10 mg/d over the test period. Extensive testing including invasive urodynamics, multiple voiding diaries, and symptoms scores at each dosage level was carried out. We found that flow rates increased moderately from baseline in a dose dependent fashion. At the 10 mg/d dosage some patients achieved flow rates in the low normal range. Patients on treatment documented a decrease in the number of voidings per day, a decrease in nocturia, an increase in bladder capacity and the volume of each voiding. On the other hand, patients frequently did not appreciate changes in their voiding patterns, as reflected in their responses to the symptom questionnaires. We could not demonstrate significant changes in bladder pressures on cystometry either during filling or voiding. Our data suggested that terazosin may well have a direct effect on the fundus of the aging bladder to increase capacity, and, through the well-known relationship between voided volume and flow rate, increase urinary flow rate.

Long-term treatment of benign prostatic hyperplasia with alfuzosin: a 12-18 month assessment. BPHALF Group

In order to assess the efficacy and safety of alfuzosin, an alpha-1 blocker, in symptomatic patients with benign prostatic hyperplasia (BPH), 131 patients who had completed a 6-month placebo-controlled trial conducted on parallel groups entered a 12-month open study; 122 patients were treated with alfuzosin for 12 months and 56 patients for 18 months. After 12 months, all obstructive and irritative symptoms assessed according to the Boyarsky scale were significantly improved, as were peak flow rates in obstructed patients and mean flow rates and residual urine in the whole population. Voiding symptoms showed sustained improvement after treatment for 12 to 18 months. Only 5.3% of patients experienced vasodilatory side effects, none of which led to withdrawal from the study. No side effect related to long-term administration was reported. Alfuzosin has a beneficial effect on voiding symptoms in patients with BPH and can be safely used in long-term administration.

Automatic integrated circuit card system for recording 24-hour uroflowmetry

A new system for obtaining accurate and stable urine flow data was developed, in which patients have a key role in recording their own urinary flow data. Flow curves and urination data are recorded on an integrated circuit card, which the patient carries in a pocket. Before urinating, the patient inserts the card into the system. Urination data are recorded automatically. The card can record up to 14 days worth of urination data. A personal computer then calculates and prints all of the flow curves including maximum flow rate, average flow rate, voided volume, duration time, hesitation time, and date and time of urination. This system is useful for detecting subtle changes in urination patterns. Typical circadian rhythms for urination can also be recorded. With this integrated circuit card system the clinical course under alpha-blocker administration could be precisely monitored.

Randomized discontinuation trials: utility and efficiency

The randomized discontinuation trial (RDT) is a two-phase trial. In phase I all patients are openly treated with the medication being evaluated. In phase II, those who have responded are randomly assigned to continue the same treatment or switch to placebo. Usually, non-compliers and "adverse reactors" identified in phase I are excluded from phase II. To investigate the value of this design, we reviewed the advantages and limitations of discontinuation studies, and compared the RDT design to the classic randomized clinical trial design in terms of clinical utility and efficiency (sample size). A computer model was used to study the efficiency of the two designs under a broad range of assumptions. The RDT design is particularly useful in studying the effect of long-term, non-curative therapies, especially when the clinically important effect is relatively small, and the use of placebo should be minimized for ethical or feasibility reasons. However, its use is limited if the objective of an investigation is to estimate the magnitude of absolute treatment effects and toxic effects in the source population, or to evaluate a potentially curative treatment. Our results indicate that selecting responders prior to randomization has a very strong effect on the relative efficiency of the trial. Further improvement may be achieved by excluding non-compliers and adverse reactors. Under the assumptions tested in our model, the sample size required in phase II of an RDT was only 20-50% of that in a classic trial.

Medical treatment of benign prostatic hyperplasia: 5 alpha-reductase inhibitors and alpha-adrenergic antagonists

Benign prostatic hyperplasia (BPH), a nonmalignant neoplasm of the prostatic epithelial and stromal tissue, occurs commonly in elderly men. The "gold standard" of care for symptomatic BPH has been and remains transurethral resection of the prostate. This operation, however, like any surgical procedure, has associated morbidity and imposes an appreciable expense on the health-care system; therefore, enthusiasm for the development of medical therapies for the management of symptomatic BPH has been substantial. Currently, practicing physicians have two types of medications for the treatment of symptomatic BPH: 5 alpha-reductase inhibitors and alpha-adrenergic antagonists. The former drugs inhibit the conversion of testosterone to the potent prostatic androgen dihydrotestosterone. As a result, the androgenic stimulation to the prostate gland is suppressed, and the size of the prostate is decreased by approximately 25%. In some patients, this outcome decreases the mechanical obstruction of the prostatic urethra and improves micturition. alpha-Adrenergic antagonists decrease the smooth muscle tone of the bladder neck, prostatic adenoma, and prostatic capsule. After these structures have been relaxed, resistance to urine flow through the prostatic urethra can be decreased, and obstructive voiding symptoms can be resolved. Although two distinctly different mechanisms are involved, both types of medications are effective for treating BPH. Thus, in 1993, transurethral resection of the prostate is no longer the only available therapeutic option. With the advent of medical therapies, internists and primary-care physicians will have more involvement in the care of patients with BPH than previously. Therefore, urologists and nonurologists must work together to serve the needs of patients with prostatism.

Terazosin. A review of its pharmacodynamic and pharmacokinetic properties, and therapeutic potential in benign prostatic hyperplasia

Terazosin selectively antagonises alpha 1-adrenoceptor-mediated contraction of the prostate, prostatic capsule, proximal urethra and bladder base, and consequently reduces urethral pressure, bladder outlet resistance and urinary symptoms associated with symptomatic benign prostatic hyperplasia. The efficacy of terazosin is reflected in increases in peak urinary flow rate, and reductions in obstructive and irritative symptom scores compared with placebo, and reductions in residual urinary volume from baseline. Clinical improvements begin to occur within 2 weeks and have been sustained for up to 2 years. The most marked treatment effects tend to occur in patients with more severe pretreatment urinary flow abnormalities. The relatively long duration of action of terazosin, allowing once-daily administration, offers a potential clinical advantage over other alpha 1-adrenoceptor antagonists although formal compliance studies have not been reported. Terazosin is generally well tolerated, but caution is recommended at treatment initiation and when dosage adjustments are made due to an increased risk of postural hypotension and related adverse effects at these times; such a risk has also been observed with several other alpha 1-adrenoceptor antagonists. Although publication of clinical trial results with terazosin is still evolving, this drug shows promise in the treatment of patients with mild to moderate symptomatic benign prostatic hyperplasia for whom surgery is not absolutely indicated. Terazosin also shows promise as a nonsurgical treatment alternative in patients with severe symptoms who are unfit for surgery and also in those who are on long waiting lists for surgery.

Medical management of benign prostatic hyperplasia: a canine model comparing the in vivo efficacy of alpha-1 adrenergic antagonists in the prostate

Medical management of benign prostatic hyperplasia (BPH) is an alternative to surgical treatment of this disease. A major target for pharmacologic therapy is the alpha-1 adrenergic receptor, since activation of this receptor by endogenous catecholamines is thought to contribute to outlet obstruction. In the present study, we compared the potency of various alpha-1 adrenergic antagonists against epinephrine-induced contraction of the canine prostate. The drugs tested were dibenzyline, prazosin, terazosin and YM617. The rank order of potency, comparing inhibitory constants (Ki's), was found to be YM617 >> prazosin > terazosin > dibenzyline. This study is the first to compare all of these drugs directly in the prostate in vivo. The rank order of potency of the drugs is similar to the rank order of potency at other alpha-1 receptors. These results demonstrate that 1) our model is useful in confirming activity of drugs at the alpha-1 receptor and 2) the prostate alpha-1 receptor is similar to other alpha-1 receptors. Whether activity at the alpha-1 adrenergic receptor is a sufficient determinant of clinical efficacy of these drugs remains to be determined.

Placebo-controlled study of terazosin in the treatment of benign prostatic hyperplasia with 2-year follow-up

This randomised, placebo-controlled, double-blind study was performed to evaluate the efficacy and safety of once-a-day terazosin (10 mg/d) in ambulatory patients (n = 57) with benign prostatic hyperplasia (BPH). After a 4-week placebo lead-in and a 24-week treatment period with terazosin (with both phases being single-blind), 30 patients who responded to terazosin were randomly assigned to either the terazosin or placebo treatment group for 12 weeks. During the single-blind treatment period, the peak urine flow rate increased 54% from a baseline average of 7.76 ml/s to 11.92 ml/s after terazosin administration; the mean flow rate increased 55% from a baseline of 4.90 ml/s to 7.59 ml/s; and the residual volume decreased 56% from 93.1 ml to 40.7 ml. The mean obstructive symptom score, irritative symptom score and physician global assessment score improved by 68%, 34% and 27%, respectively. All these changes were significant when compared with baseline values. During the double-blind period, the improvement in all the variables was sustained in the terazosin group but not in the placebo group. Peak and mean urinary flow rates, and physician assessment showed significant differences at the end of the double-blind period. Adverse events occurred only during the single-blind period. The most frequently experienced events were headache (n = 6), asthenia (n = 3) and hypotension (n = 3). A follow-up study that initially included 12 patients showed no significant loss of improvement in symptoms and no change in urodynamic parameters with the 5 mg terazosin dose at 1 year. At 2 years, the 9 remaining patients showed sustained improvement and no signs of tachyphylaxis.

A randomized, placebo-controlled multicenter study of the efficacy and safety of terazosin in the treatment of benign prostatic hyperplasia

The clinical manifestations of benign prostatic hyperplasia (BPH) are related primarily to bladder outlet obstruction resulting from enlargement of the prostate gland. Transurethral prostatectomy is the most common treatment currently offered for BPH in the United States. The primary objective of the present randomized placebo controlled multicenter study was to determine the efficacy and safety of terazosin, a selective long-acting alpha 1-blocker, for the treatment of symptomatic BPH. A total of 285 men with symptomatic BPH was randomly assigned in equal proportions to receive placebo, or 2, 5 or 10 mg. terazosin administered once daily. Of the patients 237 completed the 4-week single-blind placebo lead-in and 12-week double-blind treatment periods. The primary outcome parameters were changes in peak and mean urinary flow rates, and changes in the Boyarsky symptom scores. All terazosin treatment groups exhibited significantly greater decreases in total Boyarsky symptom score than the placebo group. The 10 mg. terazosin group exhibited significantly greater increases in peak and mean urinary flow rates than the placebo group. The improvements in symptom scores and urinary flow rates did not reach a plateau within the dose range evaluated, suggesting that further efficacy may be achieved with doses of terazosin exceeding 10 mg. This study unequivocally demonstrates the safety and efficacy of terazosin for the treatment of BPH. Selective alpha 1-blockade is likely to gain widespread acceptance for the treatment of BPH due to its safety and efficacy.

Terazosin in the treatment of benign prostatic hyperplasia: a multicentre, placebo-controlled trial

The dynamic component of bladder outflow obstruction due to benign prostatic hyperplasia (BPH) has been shown to be modified by alpha 1 adrenergic receptors. Terazosin is an alpha 1 receptor-blocking agent with a long half-life permitting once-daily dosing. This drug was administered in a multicentre, randomised, placebo-controlled trial involving patients with symptomatic bladder outflow obstruction. Of 132 patients recruited for the study, 86 were randomised to receive placebo or terazosin, 81 completed the study, and 80 were considered eligible for efficacy analysis. All terazosin treatment groups showed dramatic improvement in obstructive symptoms when compared with the placebo group, but these differences were not statistically significant because of the small numbers of patients in each group. There were improvements in peak urinary flow rates, mean urinary flow rates, and residual urine volumes for the placebo and terazosin groups, but there were no statistically significant differences in the changes between the groups. Terazosin was well tolerated by patients in this study and may provide symptomatic relief in patients with BPH.

A 12-week placebo-controlled double-blind study of prazosin in the treatment of prostatic obstruction due to benign prostatic hyperplasia

A series of 93 normotensive patients with benign prostatic hyperplasia and maximum urinary flow rates < 15 ml/s, treated at 2 hospital centres using an identical protocol, was randomly assigned to receive a 12-week course of treatment with prazosin or placebo in a double-blind parallel group trial. A total of 75 patients completed the study and were suitable for the final analysis. Prazosin was administered orally in doses of 0.5 mg and then 1 mg twice daily for 4 days and 2 mg twice daily for the remainder of the trial. Patients on treatment with prazosin exhibited a significantly increased maximum urinary flow rate as compared with placebo, with a significant reduction in maximum voiding detrusor pressure. Prazosin therapy did not produce a significant effect on either frequency or standard parameters of detrusor instability. A double-blind overall assessment of drug efficacy and tolerance significantly favoured prazosin therapy. A total of 30 patients receiving prazosin and 28 receiving placebo reported varied adverse effects. Eighteen patients were excluded from the final analysis, 10 being withdrawn because of adverse effects, 7 on treatment with prazosin and 3 in the placebo group. In long-term usage oral prazosin was well tolerated and appeared to improve obstructed voiding in patients with benign prostatic hyperplasia.

Terazosin: a new alpha adrenoceptor blocking drug

Terazosin (Hytrin; Abbott Laboratories, North Chicago, IL) is a new, selective alpha 1-adrenoceptor blocking agent used on once-a-day basis for therapy of mild-to-moderate hypertension. Its pharmacologic properties are similar to those of prazosin. Terazosin however, differs from prazosin in that its water solubility is 25 times greater than that of prazosin and its elimination half-life is about three times that of prazosin. Greater water solubility facilitates intravenous formulation, and longer half-life allows once-daily administration of terazosin. Terazosin is effective in lowering blood pressure and has a beneficial effect on plasma lipid profile. The major advantage of terazosin compared with prazosin, however, is its long duration of action. Terazosin is safe and effective when used in combination with diuretics and other antihypertensive agents, and in the long-term treatment of patients with mild to moderate essential hypertension.

Urinary flow rates in patients with benign prostatic hypertrophy following treatment with alfuzosin. DUALF Group

In order to document further the onset of action of alfuzosin, a selective alpha-1 blocker, 93 symptomatic patients with benign prostatic hypertrophy were randomly allocated to a single oral dose of either alfuzosin 1.25 mg or 2.5 mg, or placebo, after a 1-week placebo lead-in period. The effects on flow rates were assessed 1 h 30 min after administration. Peak and mean flow rates were significantly increased in the alfuzosin groups, as compared with placebo, in a dose-dependent manner. After a single intake of placebo, the mean values of these 2 parameters showed little change. The effect on the cardiovascular system (heart rate and blood pressure) was mild. This study indicates that the action of alfuzosin is already present 1 h 30 min after administration.

The response to alpha blockade in benign prostatic hyperplasia is related to the percent area density of prostate smooth muscle

The objective of the present study was to determine whether the smooth muscle content of the prostate adenoma is related to the clinical response to terazosin, a long-acting selective alpha 1 blocker. Multiple random biopsies of the prostate were obtained from 26 male subjects with symptomatic benign prostatic hyperplasia (BPH) prior to initiating therapy with terazosin. Double immunoenzymatic staining and computer-assisted quantitative color image analysis were utilized to quantify the area density of smooth muscle, connective tissue, glandular epithelium, and glandular lumen. The clinical response to alpha blockade was based upon changes in peak urinary flow rate and the Boyarsky symptom score. A significant direct relationship was observed between the percent area density of smooth muscle and the percent change in peak urinary flow rate. A statistically significant correlation between the percent area density of smooth muscle and the percent change in Boyarsky symptom score was not observed. The percent area density of prostate smooth muscle in the subjects exhibiting a favorable clinical response was 38% greater than the nonresponders (P = 0.068). The clinical response to alpha blockade in BPH is related to the area density of prostate smooth muscle.

Alpha 1 blockers. Safe, effective treatment for hypertension

Alpha 1-adrenergic blocking agents, used alone or in combination with other medications, are efficacious in the management of hypertension. They are safe and well tolerated, and they offer unique advantages. Their mechanism of action in lowering blood pressure targets elevated peripheral vascular resistance, which is the principal hemodynamic abnormality of essential hypertension. The alpha 1 blockers maintain cardiac output and blood flow to vital organs, and they do not affect renin release. These agents have beneficial lipid and metabolic effects and can improve left ventricular hypertrophy, theoretically having a positive impact on cardiovascular morbidity and mortality. The only drug interaction identified with the alpha 1 blockers is an increased hypotensive effect when they are combined with other antihypertensive agents. A further advantage of the alpha 1 blockers is that, because of the widespread location of alpha 1 receptors, the agents offer potential benefit for a number of disease states, including benign prostatic hyperplasia. They also provide an especially useful antihypertensive choice for middle-aged and elderly patients.

The efficacy and safety of terazosin for the treatment of symptomatic BPH

At least 16 clinical investigations have documented the effectiveness of alpha blockade for BPH. In the present review, four clinical studies evaluating the efficacy and safety of terazosin, a selective long-acting alpha 1 blocker, for symptomatic BPH are reviewed. The unique features of these clinical investigations are: the study designs established detailed inclusion and exclusion criteria, the outcome assessments were based upon quantitative outcome parameters, large cohorts of homogeneous patients were enrolled, and appropriate statistical methods were utilized. The dose of terazosin was titrated to maximal doses ranging between 5-20 mg. Only four of the 163 patients developed orthostatic hypotension. Overall, the peak and mean uroflow rates increased 50% and 46%, respectively (P less than 0.001). The cumulative improvement in the mean obstructive, irritative, and total symptom scores was 67%, 35%, and 54%, respectively (P less than 0.001). The present review of terazosin in males with symptomatic BPH supports the following conclusions: (1) the dose of terazosin can be safely titrated to 10 mg in normotensive and hypertensive patients with symptomatic BPH; (2) the adverse events associated with doses of terazosin up to 10 mg are relatively mild and reversible; and (3) the improvements in the outcome parameters (symptom scores and urinary flow rates) are clinically and statistically significant. Although the ultimate role of terazosin for symptomatic BPH will be determined by multi-center randomized placebo-controlled studies, the present review provides further evidence that selective alpha 1 blockers are effective and safe for the treatment of symptomatic BPH.