Androderm

2.1 Dosing Information

Prior to initiating ANDRODERM, confirm the diagnosis of hypogonadism by ensuring that serum testosterone concentrations have been measured in the morning on at least two separate days and that these serum testosterone concentrations are below the normal range.

The recommended starting dose is one ANDRODERM 4 mg/day system (not two 2 mg/day systems) applied nightly for 24 hours, delivering approximately 4 mg of testosterone per day.  To ensure proper dosing, approximately 2 weeks after starting therapy, the early morning serum testosterone concentration should be measured following system application the previous evening. Serum concentrations outside the range of 400 - 930 ng/dL require increasing the daily dose to 6 mg (i.e., one 4 mg/day and one 2 mg/day system) or decreasing the daily dose to 2 mg (i.e., one 2 mg/day system), maintaining nightly application.

Patients currently maintained on ANDRODERM 2.5 mg/day, 5 mg/day, and 7.5 mg/day may be switched to the 2 mg/day, 4 mg/day, and 6 mg/day dosage using the following schema:

• Patients using 2.5 mg daily may be switched to 2 mg/day systems at the next scheduled dose.
  
• Patients using 5 mg daily may be switched to 4 mg/day systems at the next scheduled dose.
  
• Patients using 7.5 mg daily may be switched to 6 mg (2 mg/day and 4 mg/day systems) at the next scheduled dose.

To ensure proper dosing, approximately 2 weeks after switching therapy, the early morning serum testosterone concentration should be measured following system application the previous evening.

The adhesive side of the ANDRODERM system should be applied to a clean, dry area of the skin on the back, abdomen, upper arms, or thighs. Avoid application over bony prominences or on a part of the body that may be subject to prolonged pressure during sleep or sitting (e.g., the deltoid region of the upper arm, the greater trochanter of the femur, and the ischial tuberosity). DO NOT APPLY TO THE SCROTUM. The sites of application should be rotated, with an interval of 7 days between applications to the same site. The area selected should not be oily, damaged, or irritated.

The system should be applied immediately after opening the pouch and removing the protective release liner. The system should be pressed firmly in place, making sure there is good contact with the skin, especially around the edges.

The patient should avoid swimming, showering, or washing the administration site for a minimum of 3 hours after application [see  Clinical Pharmacology (12.3)].

Mild skin irritation may be ameliorated by treatment of the affected skin with over-the-counter topical hydrocortisone cream applied after system removal. Applying a small amount of 0.1% triamcinolone acetonide cream to the skin under the central drug reservoir of the ANDRODERM system has been shown to reduce the incidence and severity of skin irritation.

8.1 Pregnancy

Risk Summary

ANDRODERM is contraindicated in pregnant women. Testosterone is teratogenic and may cause fetal harm when administered to a pregnant woman based on data from animal studies and its mechanism of action [see Contraindications ( 4) and Clinical Pharmacology ( 12.1)]. Exposure of a female fetus to androgens may result in varying degrees of virilization. In animal developmental studies, exposure to testosterone in utero resulted in hormonal and behavioral changes in offspring and structural impairments of reproductive tissues in female and male offspring. These studies did not meet current standards for nonclinical development toxicity studies. Data

Animal Data

In developmental studies conducted in rats, rabbits, pigs, sheep and rhesus monkeys, pregnant animals received intramuscular injection of testosterone during the period of organogenesis. Testosterone treatment at doses that were comparable to those used for testosterone replacement therapy resulted in structural impairments in both female and male offspring. Structural impairments observed in females included increased ano-genital distance, phallus development, empty scrotum, no external vagina, intrauterine growth retardation, reduced ovarian reserve, and increased ovarian follicular recruitment. Structural impairments seen in male offspring included increased testicular weight, larger seminal tubular lumen diameter, and higher frequency of occluded tubule lumen. Increased pituitary weight was seen in both sexes.

Testosterone exposure in utero also resulted in hormonal and behavioral changes in offspring. Hypertension was observed in pregnant female rats and their offspring exposed to doses approximately twice those used for testosterone replacement therapy.

8.2        Lactation

Risk Summary

ANDRODERM is not indicated for use in women.

8.3 Females and Males of Reproductive Potential

Infertility

Testicular abnormalities have been identified during use of ANDRODERM [see Adverse Reactions ]. Reduced fertility is observed in some men taking testosterone replacement therapy. Testicular atrophy, subfertility, and infertility have also been reported in men who abuse anabolic androgenic steroids [see Drug Abuse and Dependence ]. With either type of use, the impact on fertility may be irreversible.

8.4 Pediatric Use

Safety and efficacy of ANDRODERM have not been established in males <18 years of age. Improper use may result in acceleration of bone age and premature closure of epiphyses.

8.5 Geriatric Use

There have not been sufficient numbers of geriatric patients involved in controlled clinical studies utilizing ANDRODERM to determine whether efficacy in those over 65 years of age differs from younger patients. Additionally, there are insufficient long-term safety data in geriatric patients utilizing ANDRODERM to assess a potential incremental risk of cardiovascular disease and prostate cancer.

8.6 Renal Impairment

No studies were conducted in patients with renal impairment.

8.7 Hepatic Impairment

No studies were conducted in patients with hepatic impairment.

5.1 Worsening of Benign Prostatic Hyperplasia and Potential Risk of Prostate Cancer

• Monitor patients with benign prostatic hyperplasia (BPH) for worsening of signs and symptoms of BPH.
  
• Patients treated with androgens may be at increased risk for prostate cancer. Evaluate patients for prostate cancer prior to initiating treatment. It is appropriate to re-evaluate patients 3 to 6 months after initiation of treatment, and then in accordance with prostate cancer screening practices [see Contraindications (4)].

5.2 Polycythemia

Increases in hematocrit, reflective of increases in red blood cell mass, may require lowering or discontinuation of testosterone. Check hematocrit prior to initiating testosterone treatment. It is appropriate to re-evaluate the hematocrit 3 to 6 months after starting testosterone treatment, and then monitor annually. Discontinue testosterone therapy if the hematocrit becomes elevated. Testosterone therapy may be restarted when the hematocrit decreases to an acceptable level. An increase in red blood cell mass may increase the risk of thromboembolic events.

5.3 Venous Thromboembolism

There have been postmarketing reports of venous thromboembolic events, including deep vein thrombosis (DVT) and pulmonary embolism (PE), in patients using testosterone products such as ANDRODERM. Evaluate patients who report symptoms of pain, edema, warmth and erythema in the lower extremity for DVT and those who present with acute shortness of breath for PE. If a venous thromboembolic event is suspected, discontinue treatment with ANDRODERM and initiate appropriate workup and management [see Adverse Reactions (6.2)].

5.4 Cardiovascular Risk

Long term clinical safety trials have not been conducted to assess the cardiovascular outcomes of testosterone replacement therapy in men. To date, epidemiologic studies and randomized controlled trials have been inconclusive for determining the risk of major adverse cardiovascular events (MACE) such as non-fatal myocardial infarction, non-fatal stroke, and cardiovascular death, with the use of testosterone compared to non-use. Some studies, but not all, have reported an increased risk of MACE in association with use of testosterone replacement therapy in men. Patients should be informed of this possible risk when deciding whether to use or to continue to use ANDRODERM.

5.5 Abuse of Testosterone and Monitoring of Serum Testosterone Concentrations

Testosterone has been subject to abuse, typically at doses higher than recommended for the approved indication and in combination with other anabolic androgenic steroids. Anabolic androgenic steroid abuse can lead to serious cardiovascular and psychiatric adverse reactions [see Drug Abuse and Dependence (9)].

If testosterone abuse is suspected, check serum testosterone concentrations to ensure they are within therapeutic range. However, testosterone levels may be in the normal or subnormal range in men abusing synthetic testosterone derivatives. Counsel patients concerning the serious adverse reactions associated with abuse of testosterone and anabolic androgenic steroids. Conversely, consider the possibility of testosterone and anabolic androgenic steroid abuse in suspected patients who present with serious cardiovascular or psychiatric adverse events.

5.6 Use in Women

Due to lack of controlled studies in women and potential virilizing effects, ANDRODERM is not indicated for use in women [see  Contraindications (4) and Use in Specific Populations ( 8.1, 8.3)].

5.7 Potential for Adverse Effects on Spermatogenesis

At large doses of exogenous androgens, including ANDRODERM, spermatogenesis may be suppressed through feedback inhibition of pituitary follicle-stimulating hormone (FSH) that could lead to adverse effects on semen parameters including reduction of sperm count.

5.8 Hepatic Adverse Effects

Prolonged use of high doses of orally active 17-alpha-alkyl androgens (methyltestosterone) has been associated with serious hepatic adverse effects (peliosis hepatis, hepatic neoplasms, cholestatic hepatitis, and jaundice). Peliosis hepatis can be a life-threatening or fatal complication. Long-term therapy with intramuscular testosterone enanthate has produced multiple hepatic adenomas. ANDRODERM is not known to cause these adverse effects.

5.9 Edema

Androgens, including ANDRODERM, may promote retention of sodium and water. Edema, with or without congestive heart failure, may be a serious complication in patients with pre-existing cardiac, renal, or hepatic disease [see Adverse Reactions (6)].

5.10 Gynecomastia

Gynecomastia may develop and persist in patients being treated with androgens, including ANDRODERM, for hypogonadism.

5.11 Sleep Apnea

The treatment of hypogonadal men with testosterone may potentiate sleep apnea in some patients, especially those with risk factors such as obesity and chronic lung disease.

5.12 Lipids

Changes in serum lipid profile may require dose adjustment or discontinuation of testosterone therapy.

5.13 Hypercalcemia

Androgens, including ANDRODERM, should be used with caution in cancer patients at risk of hypercalcemia (and associated hypercalciuria). Regular monitoring of serum calcium concentrations is recommended in these patients.

5.14 Decreased Thyroxine-Binding Globulin

Androgens, including ANDRODERM, may decrease concentrations of thyroxine-binding globulins, resulting in decreased total T4 serum concentration and increased resin uptake of T3 and T4. Free thyroid hormone concentration remains unchanged and there is no clinical evidence of thyroid dysfunction.

5.15 Magnetic Resonance Imaging (MRI)

Skin burns have been reported at the application site in patients wearing an aluminized transdermal system during a magnetic resonance imaging scan (MRI). Because ANDRODERM contains aluminum, it is recommended to remove the system before undergoing an MRI. 

6.1 Clinical Trials Experience

Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared with rates in the clinical trials of another drug and may not reflect the rates observed in practice.

Table 1 shows the adverse reactions that were reported by > 3% of 36 hypogonadal men who were treated with ANDRODERM 2 mg/day, 4 mg/day, or 6 mg/day for 28 days. Of note, all hypogonadal men studied had been stable users of topical testosterone replacement products prior to the study and there was no washout period between therapies. Furthermore, there was only one subject titrated to 6 mg/day and he withdrew from the study prematurely. 

Other less common adverse reactions reported by < 3% of patients included: application site erythema, application site exfoliation, chills, diarrhea, fatigue, gastroesophageal reflux disease, hemarthrosis, hematuria, headache, polyuria, and prostatitis. The overall incidence of application site reactions of any kind was 28% (10 subjects with 13 adverse reactions).

No serious adverse reactions to ANDRODERM 2 mg/day and 4 mg/day were reported during the clinical trial.

Table 2 shows the adverse reactions that were reported in > 3% of 122 patients in clinical studies with ANDRODERM dosage strengths of 2.5 mg/day, 5 mg/day, and 7.5 mg/day. The most common adverse reactions reported were application site reactions. Transient mild to moderate erythema was observed at the site of application in the majority of patients at some time during treatment. The overall incidence of application site reactions of any kind was 48% (59 subjects with 107 adverse reactions).

The following reactions occurred in less than 3% of patients: rash, gastrointestinal bleeding, fatigue, body pain, pelvic pain, hypertension, peripheral vascular disease, increased appetite, accelerated growth, anxiety, confusion, decreased libido, paresthesia, thinking abnormalities, vertigo, acne, bullae at application site, mechanical irritation at application site, rash at application site, contamination of application site, prostate carcinoma, dysuria, hematuria, impotence, urinary incontinence, urinary tract infection, and testicular abnormalities.

6.2 Postmarketing Experience

The following adverse reactions have been identified during postapproval use of ANDRODERM. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure.

Cardiovascular Disorders:

Myocardial infarction, stroke [see Warnings and Precautions (5.4)]

Vascular Disorders:
Venous thromboembolism [see Warnings and Precautions (5.3)]

7.1 Insulin

Changes in insulin sensitivity or glycemic control may occur in patients treated with androgens. In diabetic patients, the metabolic effects of androgens may decrease blood glucose and, therefore, insulin requirement.

7.2 Oral Anticoagulants

Changes in anticoagulant activity may be seen with androgens. More frequent monitoring of INR and prothrombin time is recommended in patients taking anticoagulants, especially at the initiation and termination of androgen therapy.

7.3 Corticosteroids

The concurrent use of testosterone with ACTH or corticosteroids may result in increased fluid retention and should be monitored, particularly in patients with cardiac, renal or hepatic disease.

7.4 Triamcinolone

• The topical administration of 0.1% triamcinolone cream to the skin under the central drug reservoir prior to the application of the ANDRODERM system did not significantly alter transdermal absorption of testosterone; however, the rate of complete adherence was lower.
  
• Pretreatment with triamcinolone ointment formulation significantly reduced testosterone absorption from the ANDRODERM system.

12.1 Mechanism of Action

Endogenous androgens, including testosterone and dihydrotestosterone (DHT), are responsible for the normal growth and development of the male sex organs and for maintenance of secondary sex characteristics. These effects include the growth and maturation of prostate, seminal vesicles, penis and scrotum; the development of male hair distribution, such as facial, pubic, chest and axillary hair; laryngeal enlargement; vocal cord thickening; and alterations in body musculature and fat distribution. Testosterone and DHT are necessary for the normal development of secondary sex characteristics.

Male hypogonadism, a clinical syndrome resulting from insufficient secretion of testosterone, has two main etiologies. Primary hypogonadism is caused by defects of the gonads, such as Klinefelter Syndrome or Leydig cell aplasia, whereas secondary hypogonadism is the failure of the hypothalamus (or pituitary) to produce sufficient gonadotropins (FSH, LH).

12.2 Pharmacodynamics

No specific pharmacodynamic studies were conducted using ANDRODERM.

12.3 Pharmacokinetics

Absorption

ANDRODERM delivers physiologic amounts of testosterone, producing circulating testosterone concentrations that approximate the normal concentration range (300 - 1030 ng/dL) seen in healthy men. ANDRODERM provides a continuous daily dose of testosterone in a self-contained transdermal system. Following ANDRODERM application, testosterone is continuously absorbed during the 24-hour dosing period with a median (range) Tmax of 8 (4-12) hours.

Distribution

Circulating testosterone is primarily bound in the serum to sex hormone-binding globulin (SHBG) and albumin. Approximately 40% of testosterone in plasma is bound to SHBG, 2% remains unbound (free) and the rest is bound to albumin and other proteins.

Metabolism

Testosterone is metabolized to various 17-keto steroids through two different pathways. The major active metabolites of testosterone are estradiol and dihydrotestosterone (DHT).

During steady-state pharmacokinetic studies in hypogonadal men treated with ANDRODERM, the average DHT:T and E2:T ratios were approximately 1:10 and 1:200, respectively.

Excretion

There is considerable variation in the half-life of testosterone as reported in the literature, ranging from 10 to 100 minutes. About 90% of a dose of testosterone given intramuscularly is excreted in the urine as glucuronic and sulfuric acid conjugates of testosterone and its metabolites; about 6% of a dose is excreted in the feces, mostly in the unconjugated form. Inactivation of testosterone occurs primarily in the liver.

Upon removal of the ANDRODERM systems, serum testosterone concentrations decrease with an apparent half-life of approximately 70 minutes. Hypogonadal concentrations are reached within 24 hours following system removal. There is no accumulation of testosterone during continuous treatment.

Effect of Showering

In a two-way crossover study, the effects of showering on the pharmacokinetics of total testosterone following a single application of ANDRODERM 4 mg/day were assessed in 16 hypogonadal males. Showering 3 hours after application of ANDRODERM increased Cavg by 0.5% and decreased Cmax by 0.4% respectively, as compared to not showering. The systemic exposure to ANDRODERM was similar following applications with or without showering 3 hours after application.

13.1 Carcinogenesis, Mutagenesis, Impairment of Fertility

Carcinogenesis

Testosterone has been tested by subcutaneous injection and implantation in mice and rats. In mice, the implant induced cervical-uterine tumors, which metastasized in some cases. There is suggestive evidence that injection of testosterone into some strains of female mice increases their susceptibility to hepatoma. Testosterone is also known to increase the number of tumors and decrease the degree of differentiation of chemically induced carcinomas of the liver in rats.

Mutagenesis

Testosterone was negative in the in vitro Ames and in the in vivo mouse micronucleus assays.

Impairment of Fertility

The administration of exogenous testosterone has been reported to suppress spermatogenesis in the rat, dog and non-human primates, which was reversible on cessation of the treatment.