Jerusalem based Teva Pharmaceutical Industries Ltd., has announced the U.S. launch of generic equivalents to GlaxoSmithKline’s Avodart (dutasteride) capsules, 0.5 mgs. Dutasteride is a medication used to treat symptoms of benign prostatic hyperplasia (BPH), AKA “enlarged prostate” or benign prostatic obstruction — a condition typically afflicting men of middle age and up.
Teva was first to file and expects to be the exclusive supplier of generic dutasteride in the U.S. for several weeks. GlaxoSmithKline’s annual sales in the United States of Avodart (dutasteride) capsules amounted to approximately $467 million as of July 2015, according to IMS data.
The National Institute of Diabetes and Digestive and Kidney Diseases describes BPH as non-cancerous enlargement prostate gland, noting that the prostate goes through two main growth periods as a man ages. The first occurs early in puberty, when the prostate doubles in size, with the second growth phase of growth beginning around age 25 and continuing throughout most of the rest of a mans life. Benign prostatic hyperplasia typically occurs during the second growth phase, and is the most common prostate problem for men older than age 50.
As the prostate enlarges, the gland presses against and pinches the urethra — the tube that carries urine from the bladder to outside of the body. The bladder wall gradually becomes thicker, and eventually may weaken with the bladder losing its ability to empty completely and retaining some urine. Narrowing of the urethra and urinary retention cause many of the problems associated with BPH.
Why some men develop benign prostatic hyperplasia is not well understood; however, it occurs mainly in older men so the cause may be related to aging as the amount of active testosterone in the blood diminishes leaving a higher proportion of estrogen, with some studies suggesting that BPH may occur when the higher levels of estrogen within the prostate increase activity of substances that promote prostate cell growth.
Another theory focuses on dihydrotestosterone (DHT), a male hormone that plays a role in prostate development and growth. The NIDDK notes that some research has indicated that even with a drop in blood testosterone levels, older men continue to produce and accumulate high levels of DHT in the prostate, and it is speculated that this accumulation of DHT may encourage prostate cells to continue growing, since it has been observed that that men who do not produce DHT do not develop BPH. Dutasteride is a 5 alpha-reductase enzyme inhibitor that works by lowering production of dihydrotestosterone.
The NIDDK estimates that in 2010, as many as 14 million men in the United States had lower urinary tract symptoms suggestive of BPH, which affects about 50 percent of men between the ages of 51 and 60 and up to 90 percent of men older than 80.
Men with the following factors are more likely to develop benign prostatic hyperplasia:
• Age 40 years and older
• Family history of benign prostatic hyperplasia
• Medical conditions such as obesity, heart and circulatory disease, and type 2 diabetes
• Lack of physical exercise
• Erectile dysfunction
Lower urinary tract symptoms suggestive of BPH may include:
• Urinary frequency – urination eight or more times a day
• Urinary urgency-the inability to delay urination
• Trouble starting a urine stream
• A weak or an interrupted urine stream
• Dribbling at the end of urination
• Nocturia — frequent urination during periods of sleep
• Urinary retention
• Urinary incontinence – the accidental loss of urine
• Pain after ejaculation or during urination
• Urine that has an unusual color or smell
While symptoms of BPH most often derive from a bladder overworked from trying to pass urine through a partially blocked urethra the size of the prostatic enlargement does not always determine blockage severity or intensity of symptoms. Some men with greatly enlarged prostates have little blockage and few symptoms, while others who have minimally enlarged prostates experience greater blockage and more symptoms. Fewer than half of all men with benign prostatic hyperplasia have lower urinary tract symptoms.
Sometimes men may not become aware that they have urethral blockage until they cannot urinate — a condition, called acute urinary retention that can for example result from taking over-the-counter cold or allergy medications that contain decongestants, such as pseudoephedrine and oxymetazoline. A potential side effect of these medications is that they may prevent the bladder neck from relaxing and releasing urine. Medications containing antihistamines, such as diphenhydramine, can also weaken the contraction of bladder muscles and cause urinary retention, difficulty urinating, and painful urination. Urinary retention from partial urethra blockage may also be associated with alcohol consumption, cold temperatures, or long periods of inactivity.
Complications of benign prostatic hyperplasia may include:
• Acute urinary retention
• Chronic, or long lasting, urinary retention
• Blood in the urine
• Urinary tract infections (UTIs)
• Bladder damage
• Kidney damage
• Bladder stones
While most men with BPH do not develop these complication, kidney damage in particular can be a serious health threat when it occurs. Symptoms of benign prostatic hyperplasia also can signal more serious conditions, including prostate cancer.
Dutasteride As Therapy For BPH
According to the National Institutes of Health’s U.S. National Library of Medicine, dutasteride is used alone or with another medication (tamsulosin [Flomax]) to treat benign prostatic hyperplasia (BPH; enlargement of the prostate gland). dutasteride is used to treat symptoms of BPH and may reduce the chance of developing acute urinary retention. Dutasteride may also decrease the chance that prostate surgery will be needed. Dutasteride is in a class of medications called 5-alpha reductase inhibitors that works by blocking production of a natural substance that enlarges the prostate.
Consequently, Dutasteride capsules are indicated as a treatment for symptomatic BPH in men to: improve symptoms, reduce the risk of acute urinary retention and reduce the risk of the need for BPH-related surgery. Dutasteride capsules in combination with the alpha adrenergic antagonist, tamsulosin, are indicated for the treatment of symptomatic BPH in men with an enlarged prostate. Dutasteride capsules are not approved for the prevention of prostate cancer.
Headquartered in Israel, Teva Pharmaceutical Industries Ltd. is claimed to be the worlds largest producer of generic medicines, with its portfolio of generic products covering nearly every therapeutic area. Tevas net revenues in 2014 amounted to $20.3 billion. For more information, visit:
Teva Pharmaceutical Industries Ltd.
The National Institute of Diabetes and Digestive and Kidney Diseases
National Institutes of Health
U.S. National Library of Medicine