Dutasteride and tamsulosin are to treat benign prostatic hyperplasia. Studies show that when
given together, there is more improvement in symptoms than either drug alone. In this study,
we are looking to see if 2 different formulations of tamsulosin in our combination capsules
are the same after 7 days of dosing as the US commercial tamsulosin and dutasteride.
- Healthy as determined by a responsible physician, based on a medical evaluation
including medical history, physical examination, laboratory tests and cardiac
monitoring. A subject with a clinical abnormality or laboratory parameters outside the
reference range for the population being studied may be included only if the
Investigator and the GSK Medical Monitor agree that the finding is unlikely to
introduce additional risk factors and will not interfere with the study procedures.
Subjects with orthostasis at screening should be excluded from enrollment.
- Males between 18 and 45 years of age (inclusive).
- Male subjects must agree to use one of the contraception methods. This criterion must
be followed from the time of the first dose of study medication until follow-up from
- Body weight </ 55 kg and BMI within the range 19.0 - 30.0 kg/m2 (inclusive).
- Capable of giving written informed consent, which includes compliance with the
requirements and restrictions listed in the consent form.
- QTcB or QTcF < 450 msec.
- Subjects must agree not to donate blood and blood products for 6 months after the last
dose of study medication.
- The subject has a positive pre-study drug/alcohol screen. A minimum list of drugs that
will be screened for include amphetamines, barbiturates, cocaine, opiates,
cannabinoids and benzodiazepines.
- Slow metabolizer for CYP2D6 as determined by screening PGx analysis.
- A positive pre-study Hepatitis B surface antigen or positive Hepatitis C antibody
result within 3 months of screening.
- A positive test for HIV antibody.
- History of regular alcohol consumption within 6 months of the study defined as:
- An average weekly intake of >14 drinks/week. One drink is equivalent to: 12 g
alcohol = 5 ounces (150 mL) of wine or 12 ounces (360 mL) of beer or 1.5 ounces (45
mL) of 80 proof distilled spirits.
- The subject has participated in a clinical trial and has received an investigational
product within the following time period prior to the first dosing day in the current
study: 30 days, 5 half-lives or twice the duration of the biological effect of the
investigational product (whichever is longer).
- Exposure to more than four new chemical entities within 12 months prior to the first
- Use of prescription or non-prescription drugs, including vitamins, herbal and dietary
supplements (including St John's Wort) within 7 days (or 14 days if the drug is a
potential enzyme inducer) or 5 half-lives (whichever is longer) prior to the first
dose of study medication and until collection of the final PK sample from the study,
unless in the opinion of the Investigator and GSK Medical Monitor the medication will
not interfere with the study procedures or compromise subject safety.
- History of sensitivity to any of the study medications, or components thereof,
including sulfonamides, or a history of drug or other allergy that, in the opinion of
the investigator or GSK Medical Monitor, contraindicates their participation.
- History of postural hypotension, dizziness, poor hydration, vertigo, vaso-vagal
reactions or any other signs and symptoms of orthostasis, which in the opinion of the
investigator could be exacerbated by tamsulosin and result in putting the subject at
risk of injury.
- Orthostatic hypotension at screening, defined as a reduction in systolic blood
pressure of 20 mmHg or more and/or a reduction in diastolic blood pressure of 10 mmHg
or more for standing vs. supine measurements.
- Where participation in the study would result in donation of blood or blood products
in excess of 500 mL within a 56 day period.
- Unwillingness or inability to follow the procedures outlined in the protocol.
- History of sensitivity to heparin or heparin-induced thrombocytopenia.
- Consumption of red wine, seville oranges, grapefruit, grapefruit juice or cruciferous
vegetables (watercress, broccoli, cabbage, Brussels sprouts) from 7 days prior to the
first dose of study medication and until collection of the final PK sample in the