Cardiovascular Safety of Tamsulosin Modified Release in the Fasted and Fed State in Elderly Healthy Subjects

Development and optimization of a tamsulosin nanostructured lipid carrier loaded with saw palmetto oil and pumpkin seed oil for treatment of benign prostatic hyperplasia

Benign prostatic hyperplasia (BPH) is a nonmalignant growth of the prostate tissue and causes urinary tract symptoms. To provide effective treatment, tamsulosin (TM), saw palmetto oil (SP), and pumpkin seed oil (PSO) were combined and fabricated a nanostructured lipid carrier (NLC) as TM-S/P-NLC using experimental design. The purpose was to enhance the permeation and therapeutic activity of TM; combining TM with SP and PSO in an NLC generates a synergistic activity. An optimized TM-S/P-NLC was obtained after statistical analysis, and it had a particle size, percentage of entrapment efficiency, and steady-state flux of 102 nm, 65%, and 4.5 μg/cm².min, respectively. Additionally, the optimized TM-S/P-NLC had spherical particles with a more or less uniform size and a stability score of 95%, indicating a high level of stability. The in vitro release studies exhibited the optimized TM-S/P-NLC had the maximum release profile for TM (81 ± 4%) as compared to the TM-NLCs prepared without the addition of S/P oil (59 ± 3%) or the TM aqueous suspension (30 ± 5%). The plasma TM concentration–time profile for the TM-S/P-NLC and the marketed TM tablets indicated that when TM was supplied in a TM-S/P-NLC, the pharmacokinetic profile of the drug was improved. Simultaneously, in vivo therapeutic efficacy studies also showed favorable results for the TM-S/P-NLC in terms of the prostate weight and prostate index following treatment of BPH. Based on the findings of present study, we suggest that in the future, the TM-S/P-NLC could be a novel drug delivery system for treating BPH.

Evaluation of the pharmacokinetics and food effects of a novel formulation tamsulosin 0.4 mg capsule compared with a 0.2 mg capsule in healthy male volunteers

Tamsulosin, an alpha-1 adrenoreceptor antagonist, has been used as a primary option for medical treatment of benign prostate hyperplasia. An open-label, single-dose, randomized, three-treatment, three-period, three sequence crossover study was conducted to evaluate the pharmacokinetics (PKs) of 0.2 and 0.4 mg tamsulosin hydrochloride (HCl) in the fed versus the fasted state. Subjects were randomly assigned to three sequences and received one of the following treatments at each period: tamsulosin HCl 0.2 or 0.4 mg in the fed state with a high-fat meal, or tamsulosin HCl 0.4 mg in the fasted state. Blood samples for the PK analysis were collected at pre-dose and up to 48 h post-dose. The PK parameters were calculated by a non-compartmental method. The geometric mean ratio (GMR) and its 90% confidence intervals (CIs) of the plasma maximum concentration (C_max) and area under concentration curve from time zero to last measurable concentration (AUC_last) were calculated. Twenty-two subjects completed the study. The systemic exposure of tamsulosin 0.4 mg decreased approximately 9% in the fed state compared to the fasted state, and the time to reach peak concentration was slightly delayed in the fed state. The dose normalized GMR and its 90% CIs of C_max and AUC_last for 0.2 and 0.4 mg tamsulosin in the fed state were within 0.8 and 1.25 range. Systemic exposure of tamsulosin was decreased in the fed condition compared to the fasted condition. Linear PK profiles were observed between 0.2 and 0.4 mg tamsulosin in the fed state.

Trial Registration

ClinicalTrials.gov Identifier: NCT02529800.

Effects of CYP2D6 and CYP3A5 genetic polymorphisms on steady-state pharmacokinetics and hemodynamic effects of tamsulosin in humans

PURPOSE

Tamsulosin is one of the most potent drugs currently available to treat benign prostatic hyperplasia. Cytochrome P450 (CYP) 2D6 and CYP3A are the two major enzymes responsible for tamsulosin metabolism. The purpose of this study was to evaluate the effects of CYP2D6 and CYP3A5 genetic polymorphisms on the pharmacokinetics and hemodynamic effects of tamsulosin in humans.

METHODS

Twenty-nine male subjects were enrolled and their CYP2D6 (*2,*4,*5,*10,*14,*21,*41, and *xN) and CYP3A5 (*5) genotypes were screened. Tamsulosin was administered daily for 6 days to assess its steady-state pharmacokinetics and hemodynamic effects according to CYP2D6 and CYP3A5 genotypes.

RESULTS

CYP2D6 group 3 (with genotype *10/*10 or *5/*10) exhibited higher plasma levels than CYP2D6 group 1 (with genotype *1/*1,*1/*2,*1/*2xN, or *2/*10xN) or CYP2D6 group 2 (with genotype *1/*10,*1/*41, or *2/*5) (trough concentrations for groups 1, 2, and 3: 1.3, 1.8, and 3.8 ng/mL, respectively [P < 0.001]; peak concentrations for groups 1, 2, 3: 8.3, 10.0, and 13.8 ng/mL, respectively [P < 0.005]). Similarly, CYP2D6 genotypes influenced the hemodynamic effects of tamsulosin based on systolic and diastolic blood pressures. However, the CYP3A5*3 polymorphism did not affect tamsulosin plasma levels and its hemodynamic effects.

CONCLUSION

The CYP2D6 but not the CYP3A5 genetic polymorphisms affected the pharmacokinetics and the hemodynamic effects of tamsulosin.

Efficacy and Safety of a Fixed-Dose Combination Therapy of Tamsulosin and Tadalafil for Patients With Lower Urinary Tract Symptoms and Erectile Dysfunction: Results of a Randomized, Double-Blinded, Active-Controlled Trial

BACKGROUND

Phosphodiesterase type 5 inhibitors and α-adrenergic blocking agents (α-blockers) are widely used for the treatment of erectile dysfunction (ED) and lower urinary tract symptoms (LUTS) associated with benign prostatic hyperplasia (BPH).

AIMS

To assess the efficacy and safety of fixed-dose combinations (FDCs) of tamsulosin and tadalafil compared with tadalafil monotherapy in patients with comorbid BPH-associated LUTS and ED.

METHODS

A randomized, double-blinded, active-controlled trial was conducted of 510 men with BPH-associated LUTS and ED. Patients were treated with FDCs of tamsulosin 0.4 mg plus tadalafil 5 mg (FDC 0.4/5 mg), tamsulosin 0.2 mg plus tadalafil 5 mg (FDC 0.2/5 mg), or tadalafil 5 mg for a 12-week treatment period. For a subsequent 12-week extension period, the patients were administered FDC 0.4/5 mg.

OUTCOMES

The primary outcomes were changes from baseline in total International Prostate Symptom Score (IPSS) and International Index of Erectile Function erectile function domain (IIEF-EF) score at week 12 to prove superiority and non-inferiority of FDCs compared with tadalafil 5 mg. The safety assessments were adverse reactions, laboratory test results, and vital signs at week 24.

RESULTS

The mean changes in total IPSS and IIEF-EF scores were -9.46 and 9.17 for FDC 0.4/5 mg and -8.14 and 9.49 for tadalafil 5 mg, respectively, which indicated superiority in LUTS improvement (P = .0320) and non-inferiority in ED treatment with FDC 0.4/5 mg compared with tadalafil 5 mg. However, the results from FDC 0.2/5 mg failed to demonstrate superiority in LUTS improvement. No clinically significant adverse events regarding the investigational products were observed during the 24-week period.

CLINICAL IMPLICATIONS

The FDC 0.4/5 mg is the first combined formulation of an α-blocker and a phosphodiesterase type 5 inhibitor that offers benefits in patient compliance and as add-on therapy in patients with comorbid BPH-associated LUTS and ED.

STRENGTHS AND LIMITATIONS

The study clearly demonstrated the advantage of FDC 0.4/5 mg. The main advantage of FDC 0.4/5 mg was the enhanced efficacy on BPH-associated LUTS comorbidity with ED, the lower incidence of side effects, and the simplification and convenience of therapy, which led to better overall patient compliance. However, the lack of a tamsulosin monotherapy control group was a limitation of this study.

CONCLUSION

The FDC 0.4/5 mg therapy was safe, well tolerated, and efficacious, indicating that combination therapy could provide clinical benefits for patients with BPH-associated LUTS complaints and ameliorate the comorbidity of ED. Kim SW, Park NC, Lee SW, et al. Efficacy and Safety of a Fixed-Dose Combination Therapy of Tamsulosin and Tadalafil for Patients With Lower Urinary Tract Symptoms and Erectile Dysfunction: Results of a Randomized, Double-Blinded, Active-Controlled Trial. J Sex Med 2017;14:1018-1027.

Interactions between medications employed in treating benign prostatic hyperplasia and food - A short review

Benign prostatic hyperplasia (BPH) is the most common disease in elderly men. BPH symptoms include frequent urination, urgent tenesmus and urination at night, a weak and interrupted urine flow and a sense of incomplete emptying of the bladder. Alpha- 1 adrenergic receptor antagonists and 5 α-reductase inhibitors form the most important groups of medications employed in BPH. Appropriately managed BPH patients shall be subject to counselling on interactions between agents belonging to these groups, and on particular components of the food they have. The present review has been aimed at assessing potential effects of consumed food, alcohol and fruit juices on the pharmacokinetics and pharmacodynamics of medications for benign prostatic hyperplasia. The authors reviewed the English PubMed database covering the years 1991-2015. Additionally, a digital version of Stockley Drugs Interaction and other electronic databases such as drugs.com and Medscape were also researched; characterisation charts for particular medical products were also analyzed. Pharmacokinetics of extended-release forms of alfuzosin, doxazosin, tamsulosin and silodosin is well known to be food-sensitive. Alfuzosin, tamsulosin and silodosin due to their likely interaction with grapefruit juice and citrus fruits, may intensify adverse effects of the drugs. Alpha-1 adrenergic receptor antagonists are known to interact with alcohol, leading to orthostatic hypotension. For 5 alpha-reductase inhibitors, such as finasteride, or dutasteride, the pharmacokinetic effect due to consumed food is of no clinical importance and thus they may be taken regardless of meals. As in general grapefruit juice and alcohol tend to significantly affect the efficacy and safety of the applied drug therapy, it is highly advisable to be knowledgeable on the subject in order to educate patients.

Effects of alpha1-adrenoceptor antagonist (tamsulosin) on incident of ejaculation and semen quality in the goat

Male temporary contraception is occasionally required in some animals. Alpha1-adrenoceptor antagonist (tamsulosin) can cause ejaculation disorder. Two sets of Latin square were applied to six male goats to received either normal saline, dimethylsulphoxide or tamsulosin (179.8 nmol kg(-1) ) at 1-week interval. Semen collection and libido scoring were undertaken at 3, 6 and 24 h post-injection. For ejaculated semen, its quality was evaluated. Physiological measurements including body temperature, respiration and heart rates were measured before injection and at 30 min before semen collection. The results showed that libido score and physiological changes were not affected by treatments and time periods. Anejaculation was observed in 11 (91.7%), 5 (41.7%) and 1 (8.3%) males at 3, 6 and 24 h post-tamsulosin injection respectively. The incidence returned to normal when compared with control groups at 24 h. The percentages of motile and live spermatozoa at 6 h post-tamsulosin injection were significantly lower (P < 0.05) than that of normal saline group. At 24 h post-injection, there were no significant differences of all semen parameters among treatments. This study demonstrated that tamsulosin had temporary effects on ejaculation and semen quality without reducing sex desire and physiological functions in male goats.

Effects of strong CYP2D6 and 3A4 inhibitors, paroxetine and ketoconazole, on the pharmacokinetics and cardiovascular safety of tamsulosin

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT

Tamsulosin metabolism involves both CYP2D6 and 3A4. However, data on potential drug-drug interactions between tamsulosin and inhibitors of CYP2D6 and 3A4 are limited and information on potential pharmacodynamic consequences of such pharmacokinetic interactions is missing.

WHAT THIS STUDY ADDS

This study provides information on the drug-drug interactions of tamsulosin with strong CYP2D6 and strong CYP3A4 inhibitors after single dose administration in healthy subjects.

AIM

To determine the effect of the strong CYP2D6 inhibitor paroxetine and strong CYP3A4 inhibitor ketoconazole on the pharmacokinetics and safety (orthostatic challenge) of tamsulosin.

METHODS

Two open-label, randomized, two-way crossover studies were conducted in healthy male volunteers (extensive CYP2D6 metabolizers).

RESULTS

Co-administration of multiple oral doses of 20 mg paroxetine once daily with a single oral dose of the 0.4 mg tamsulosin HCl capsule increased the adjusted geometric mean (gMean) values of C(max) and AUC(0,∞) of tamsulosin by factors of 1.34 (90% CI 1.21, 1.49) and 1.64 (90% CI 1.44, 1.85), respectively, and increased the terminal half-life (t(1/2) ) of tamsulosin HCl from 11.4 h to 15.3 h. Co-administration of multiple oral doses of 400 mg ketoconazole once daily with a single oral dose of the 0.4 mg tamsulosin increased the gMean values of C(max) and AUC(0,∞) of tamsulosin by a factor of 2.20 (90% CI 1.96, 2.45) and 2.80 (90% CI 2.56, 3.07), respectively. The terminal half-life was slightly increased from 10.5 h to 11.8 h. These pharmacokinetic changes were not accompanied by clinically significant alterations of haemodynamic responses during orthostatic stress testing.

CONCLUSION

The exposure to tamsulosin is increased upon co-administration of strong CYP2D6 inhibitors and even more so of strong 3A4 inhibitors, but neither PK alteration was accompanied by clinically significant haemodynamic changes during orthostatic stress testing.

Age, Comorbidity and Hypertensive Co-Medication do Not Affect Cardiovascular Tolerability of 10 Mg Alfuzosin Once Daily

PURPOSE

We assessed in real-life practice the impact of age, cardiovascular comorbidity and co-medication on the tolerability and efficacy of 10 mg alfuzosin OD in men with lower urinary tract symptoms suggestive of benign prostatic obstruction.

MATERIALS AND METHODS

A total of 6,523 men with a mean age of 64.7 years were enrolled in a 6-month open label study of 10 mg alfuzosin OD. They were stratified by age quartile (younger than 60, 60 to 64, 65 to 70 and older than 70 years), comorbidity (hypertension, ischemic heart disease and diabetes) and antihypertensive co-medication (diuretics, beta-blockers, angiotensin converting enzyme inhibitors, angiotensin II inhibitors and calcium channel antagonists).

RESULTS

Alfuzosin was effective and well tolerated. Despite an increased prevalence of cardiovascular comorbidity and antihypertensive co-medication with age changes in blood pressure did not significantly differ among age groups. In controls, ie those with no cardiovascular comorbidity or co-medication, alfuzosin produced minimal decreases in sitting systolic (mean -2.6 to -2.8 mm Hg) and diastolic (mean -1.7 to -1.8 mm Hg) blood pressure. In men with cardiovascular comorbidity mean decreases in systolic (-3.5 to 5.8 mm Hg) and diastolic (-2.0 to -3.3 mm Hg) blood pressure remained marginal. Of the 6,523 exposed patients 19.3% withdrew from the study, mainly for adverse events (6.4%) or a lack of efficacy (5.3%), while 229 (3.5%) experienced serious adverse events and 1,558 (23.9%) reported at least 1 treatment emergent adverse event. The most commonly reported adverse event was dizziness/postural dizziness (4.8%). Hypotension/postural hypotension was uncommon (0.7%). Age, cardiovascular comorbidity and antihypertensive co-medication had no impact on the safety profile of 10 mg alfuzosin OD.

CONCLUSIONS

Alfuzosin (10 mg) OD is effective and well tolerated, and it has marginal effects on blood pressure, including in elderly patients and those with hypertension, ischemic heart disease or diabetes and those receiving antihypertensive agents.