Zudena

Zudena (udenafil) is an oral drug employed in the symptomatic treatment of erectile dysfunction (ED) in men. A tablet of Zudena taken 15-30 minutes before attempting sexual activity permits to engage in a satisfactory sexual intercourse, removing such signs of ED as inability to achieve or maintain penile hardness.

Zudena is the newest addition to the class of oral drugs used in ED, being a valuable compliment to tablets with well-established and universally recognized brand names like Viagra, Cialis, Levitra and, most recently, Stendra (or Spedra). Zudena active substance udenafil was originally developed by the Korean pharmaceutical company Dong-A Pharmaceutical Co., Ltd in 2011 and has been approved for the use within its country of origin since then. The patient-years of safe and fruitful use, as well as numerous clinical trials, give grounds to say that Zudena is an important contribution to the world of men’s sexual health pharmaceuticals, as it features unique pharmacokinetic profile that combines the benefits of the two flagman drugs in ED therapy, Viagra (sildenafil) and Cialis (tadalafil).

The benefits of Zudena, a novelty ED drug, as compared to existing ED drugs, are:

• shorter onset time than that of Cialis
• longer duration time than that of Viagra, Levitra and Stendra
• efficacy in daily therapy
• increased clinical tolerance during daily use as compared to Cialis
• milder side effects

Zudena active substance is udenafil, an agent developed and approved for use in ED patients in Korea in 2011. Udenafil belongs to the same class of phosphodiesterase type 5 inhibitors as sildenafil (Viagra) and other drugs in this cluster, but differs from them in terms of its onset and duration of action times, as well as PDE selectivity ratio. These pharmacokinetic characteristics make udenafil a unique substance featuring strong competitive points in comparison to every other ED drug on the market. Trials in various ethnicity groups are required for udenafil to be approved for the international use, but the data available today and the safety of its application in the country of its origin within the scope of 8 years are giving grounds to believe that it is only a matter of time before the substance gets FDA approval.

A dose of Zudena depends on the chosen dosing regimen: whether the drug is administered as an on-demand or once-daily solution. In the course of trials, the efficacy and safety of udenafil as a daily treatment agent was established at doses 25mg, 50mg and 75mg over the course of 12 week trial. Owing to this, Zudena can be seen as a beneficial alternative to Cialis Daily taken at the dose of 2.5mg or 5mg, since, due to its higher PDE11 selectivity profile, Zudena is better tolerated than tadalafil by a certain subset of patients with accentuated sensitivity to phosphodiesterase subtype inhibition.

Based on clinical efficacy and tolerance established by the physician, patients are prescribed the following doses of Zudena: 25mg, 50mg, 75mg, 100mg, 200mg and 300mg. The lower end of dosing has shown comparatively poor on-demand efficacy in placebo-controlled studies, while doses starting of udenafil 100mg and 200mg yielded results of 88.8% and 92.4% respectively. Controversially, the doses from the lower range (udenafil 25-75mg) were found efficient in daily dosing regimens.

The dose of Zudena should be established by the attending healthcare provider who is well informed about the patient’s clinical history and current health condition. The dose is determined based on severity of ED, individual response towards udenafil and the tolerance of the substance patient’s sexual habits and personal preferences, general state of health and presence of comorbid health conditions, and some other factors as determined by prescriber. The maximal dose recommended by doctor should in no event be superseded. In case of overdosing, inform your prescriber immediately and ask for further instructions.

Adults take 100 mg once a day, about 30 minutes to 12 hours before the expected sexual activity. The maximum recommended dose is once a day. Increase to 200mg should be carefully considered after confirming the adverse reaction to 100mg. This medicine can be taken independently of the meal.

No dosage adjustment is required in older male patients (65 years old or older)

Zudena is used in men with ED. Erectile dysfunction refers to the inability, constant or recurrent, to obtain or maintain an erection that allows intercourse. The psychological causes are frequent (guilt, anxiety, shame, fear), but one must also consider a physiological cause and consult a doctor, possibly a urologist. The common mistake is to believe that everything is going on in the head. Men with diabetes and heart disease, as well as smokers, are particularly prone to sexual dysfunction. A depression is often accompanied by erectile dysfunction. Also note that some medications, antidepressant type, tranquillizers, medications for heart disorders, can interfere with the mechanism of erection.

In case of erectile dysfunction different solutions can be proposed. Among the most common: drugs (phosphodiesterase type 5 inhibitors) are nowadays very often prescribed. There are many dosage forms of these drugs that help men with erectile dysfunction.

Udenafil and tadalafil share a common clinical property of being effective in daily dosing regimen. However, in clinical trials udenafil has shown a better safety margin in patients with poor tolerance towards tadalafil. This can be explained by selective inhibition of PDE11 subtype which is more potent in udenafil (according to this source, the selectivity ratio for udenafil is 96 as compared to 7.1 for tadalafil). In practice, this allows for a safer daily use of udenafil.

Udenafil has a shorter action onset compared to tadalafil, but also a shorter duration of action. Tadalafil is compatible with alcohol and its pharmacokinetics is not affected by fatty meals, while udenafil acts best when taken in a fasted state and its compatibility with alcohol is poor.

Udenafil is currently only approved in Korea, while tadalafil is approved by FDA and is prescribed by practitioners almost worldwide.

In comparison with sildenafil, udenafil has a shorter onset of action (Zudena starts producing its effect ca 30 minutes after the intake, while sildenafil take ca 60 minutes to start acting). The duration of action for udenafil is longer and stretches to 11-13 hours, while for sildenafil this parameter is 4-6 hours. Clinical tolerance of udenafil is reportedly higher than that of sildenafil. Sildenafil is not approved for daily therapy, while udenafil has proven efficacy in daily use. The effects of both agents are inhibited and delayed by simultaneous intake of fatty meals and alcohol.

Udenafil is only approved by Korean healthcare authorities; sildenafil is approved by FDA and is on prescription registry in the majority of countries.

The following subsets of patients should be treated with caution:

• Patients with anomalous penile deformities (angulation, penile tissue proliferation, or peronei)
• Patients with a status of persistent fever (sickle cell disease, multiple myelopathy, leukemia)
• Patients with liver dysfunction (GOT, GPT greater than 3 times the upper limit of normal) or patients with renal impairment (blood creatinine> 2.5 mg / dl) should be administered according to the doctor’s discretion. Safety and efficacy have not been studied in patients with liver failure or renal failure.
• Patients receiving CYP450 3A4 inhibitor (ketoconazole, itraconazole, erythromycin) (increased plasma concentration was observed, so caution should be taken such as initial dose adjustment)
• Patients with proliferative diabetic retinopathy
• Patients with hemorrhagic or active peptic ulcer
• The safety and efficacy of unregulated diabetic patients has not been studied.
• Patients receiving alpha-blockers (in the case of the same series of similar drugs, some patients may report hypotensive symptoms when used in combination with an alpha-blocker.)

The patient to be treated with this drug should examine and test the previous history to diagnose erectile dysfunction and potential risk. The use of this drug should be limited to patients requiring clinical treatment based on such objective diagnosis.

Since sexual activity involves the risk of heart disease, you should pay attention to cardiovascular conditions before starting treatment. This drug shows blood pressure lowering effect by vasodilating action, so it can enhance blood pressure lowering effect of nitrate or nitric oxide donor.

Patients who have experienced cerebral infarction, cerebral hemorrhage, or myocardial infarction within the last 6 months should not be administered. When they are administered to patients with a previous history of cerebral infarction, cerebral hemorrhage, or myocardial infarction.

This drug is not an aphrodisiac or tincture enhancer, so it cannot be used for treatment of erectile dysfunction patients.

No studies have been conducted in patients with spinal cord injury, radical prostatectomy or radical pelvic surgery, patients with low sexual desire, patients receiving chemotherapy, or patients taking anticoagulants.

Clinical trials have reported dizziness and blurred vision due to the use of this drug, so be careful when driving or operating the machine.

If a sudden loss of vision occurs in the patient’s eye (one or both eyes), the physician should advise and medical attention to discontinue use of PDE5 inhibitors, including this drug. These symptoms may be a sign of non-arteritic anterior ischemic optic neuropathy (NAION), which may be the cause of visual loss, including permanent visual loss, it has been reported rarely and has a potential interrelationship with the administration of PDE5 inhibitors. Whether these adverse events are directly linked to the administration of PDE5 inhibitors or other factors has not been determined.

The physician should inform the patient that the risk of administration of vasodilators such as PDE5 inhibitors may be increased in patients who have already experienced non-arterial anterior ischemic neuropathy in one eye.

If sudden hearing loss or hearing loss (possibly accompanied by tinnitus and dizziness) occurs, the physician should advise the patient to discontinue the use of PDE5 inhibitors, including this drug, and seek immediate medical attention.

Zudena should not be administered to the following patients.

• Patients who show hypersensitivity reactions to NSAIDs or the excipients contained in NSAIDs
• Patients taking nitrate or nitric oxide donors regularly or intermittently
• Patients whose sex is not recommended, including cardiovascular disease (eg, severe cardiovascular disease such as unstable angina or severe heart failure)
• Patients with a history of stroke, myocardial infarction or coronary artery bypass surgery within the last 6 months
• patients with hypotension below 90 / 50mmHg or patients with uncontrolled hypertension above 170 / 100mmHg, patients with uncontrolled arrhythmia
• Hereditary degenerative retinal disease already known, including pigmented retinitis
• Patients with severe hepatic dysfunction or renal failure
• Patients taking indinavir or ritonavir as HIV protease inhibitors as potent CYP450 3A4 inhibitors
• Patients taking other erectile dysfunction drugs (Safety and efficacy of this drug in combination with other erectile dysfunction drugs have not been studied and should not be used in combination with other erectile dysfunction drugs)
• atients with congenital QT prolongation syndrome or patients receiving drugs that increase QT interval
• Patients under the age of 18

Zudena was administered to 589 patients. Adverse events were usually transient and mostly mild to moderate in severity. The most common adverse reactions were facial flushing and headache. Patients were given up to 200mg once daily, and the type and frequency of adverse events were significantly increased over 100mg.

The following are adverse reactions reported in clinical trials.

Adverse events reported in further clinical trials cannot rule out the causative relationship between the drug and the causal relationship, and adverse events not identified in pre-market clinical studies may include headache, cold or numbness, palpitations, vertigo, narcolepsy, Diarrhea, difficulty breathing during exercise, coughing, nasal bleeding, increased erection, hypotension, and the like.