FINCAR Tablet Ref.[50462] Active ingredients: Finasteride

Effects on Prostate Specific Antigen (PSA) and the Use of PSA in Prostate Cancer Detection

In clinical studies, finasteride reduced serum PSA concentration by approximately 50% within six months of treatment. This decrease is predictable over the entire range of PSA values in patients with symptomatic BPH, although it may vary in individuals.

For interpretation of serial PSAs in men taking finasteride, a new PSA baseline should be established at least six months after starting treatment and PSA monitored periodically thereafter. Any confirmed increase from the lowest PSA value while on finasteride may signal the presence of prostate cancer and should be evaluated, even if PSA levels are still within the normal range for men not taking a 5α reductase inhibitor. Non-compliance with finasteride therapy may also affect PSA test results. To interpret an isolated PSA value in patients treated with finasteride for six months or more, PSA values should be doubled for comparison with normal ranges in untreated men. These adjustments preserve the utility of PSA to detect prostate cancer in men treated with finasteride.

Finasteride may also cause decreases in serum PSA in the presence of prostate cancer.

The ratio of free to total PSA (percent free PSA) remains constant even under the influence of finasteride. If clinicians elect to use percent free PSA as an aid in the detection of prostate cancer in men undergoing finasteride therapy, no adjustment to its value appears necessary.

Increased Risk of High-Grade Prostate Cancer

Men aged 55 and over with a normal digital rectal examination and PSA ≤3.0 ng/mL at baseline taking finasteride 5 mg/day in the 7-year Prostate Cancer Prevention Trial (PCPT) had an increased risk of Gleason score 8-10 prostate cancer (finasteride 1.8% vs placebo 1.1%). Similar results were observed in a 4-year placebo-controlled clinical trial with another 5α-reductase inhibitor (dutasteride) (1% dutasteride vs 0.5% placebo). 5αreductase inhibitors may increase the risk of development of high-grade prostate cancer. Whether the effect of 5α-reductase inhibitors to reduce prostate volume, or study-related factors, impacted the results of these studies has not been established.

Exposure of Women – Risk to Male Foetus

Women should not handle crushed or broken FINCAR tablets when they are pregnant or may potentially be pregnant because of the possibility of absorption of finasteride and the subsequent potential risk to the male foetus. FINCAR tablets are coated and will prevent contact with the active ingredient during normal handling, provided that the tablets have not been broken or crushed.

Pediatric Patients and Women

FINCAR is not indicated for use in pediatric patients or women.

Effect on Semen Characteristics

Treatment with finasteride for 24 weeks to evaluate semen parameters in healthy male volunteers revealed no clinically meaningful effects on sperm concentration, mobility, morphology or pH. A 0.6 mL (22.1%) median decrease in ejaculate volume, with a concomitant reduction in total sperm per ejaculate, was observed. These parameters remained within the normal range and were reversible upon discontinuation of therapy with an average time to return to baseline of 84 weeks.

Consideration of Other Urological Conditions

Prior to initiating treatment with finasteride, consideration should be given to other urological conditions that may cause similar symptoms. In addition, prostate cancer and BPH may coexist. Patients with large residual urinary volume and/or severely diminished urinary flow should be carefully monitored for obstructive uropathy. These patients may not be candidates for finasteride therapy.

Finasteride is generally well tolerated; adverse reactions usually have been mild and transient.

4-Year Placebo-Controlled Study (PLESS)

In PLESS, 1,524 patients treated with finasteride and 1,516 patients treated with placebo were evaluated for safety over a period of 4 years. The most frequently reported adverse reactions were related to sexual function. 3.7% (57 patients) treated with finasteride and 2.1% (32 patients) treated with placebo discontinued therapy as a result of adverse reactions related to sexual function, which are the most frequently reported adverse reactions.

Table 3 presents the only clinical adverse reactions considered possibly, probably or definitely drugrelated by the investigator, for which the incidence on finasteride was ≥1% and greater than placebo over the 4 years of the study. In years 2–4 of the study, there was no significant difference between treatment groups in the incidences of impotence, decreased libido and ejaculation disorder.

Table 3. Drug-related adverse experiences:

^* Combined years 2–4
N=1,524 and 1,516, finasteride vs placebo, respectively

Phase III Studies and 5-Year Open Extensions

The adverse experience profile in the 1-year, placebo-controlled, Phase III studies, the 5-year open extensions, and 4-year PLESS were similar.

Medical Therapy of Prostatic Symptoms (MTOPS) study

In the MTOPS study, 3047 men with symptomatic BPH were randomized to receive finasteride 5 mg/day (n=768), doxazosin 4 or 8 mg/day (n=756), the combination of finasteride 5 mg/day and doxazosin 4 or 8 mg/day (n=786), or placebo (n=737) for 4 to 6 years. The incidence rates of drugrelated adverse experiences reported by ≥2% of patients in any treatment group in the MTOPS Study are listed in Table 4.

The individual adverse effects which occurred more frequently in the combination group compared to either drug alone were: asthenia, postural hypotension, peripheral edema, dizziness, decreased libido, rhinitis, abnormal ejaculation, impotence and abnormal sexual function (see Table 4). Of these, the incidence of abnormal ejaculation in patients receiving combination therapy was comparable to the sum of the incidences of this adverse experience reported for the two monotherapies.

Combination therapy with finasteride and doxazosin was associated with no new clinical adverse experience.

Four patients in MTOPS reported the adverse experience breast cancer. Three of these patients were on finasteride only and one was on combination therapy. The MTOPS Study was not specifically designed to make statistical comparisons between groups for reported adverse experiences. In addition, direct comparisons of safety data between the MTOPS study and previous studies of the single agents may not be appropriate based upon differences in patient population, dosage or dose regimen, and other procedural and study design elements.

Table 4. Incidence ≥2% in One or More Treatment Groups Drug-Related Clinical Adverse Experiences in MTOPS:

Doxazosin dose was achieved by weekly titration (1 to 2 to 4 to 8 mg). The final tolerated dose (4 mg or 8 mg) was administered at end-Week 4. Only those patients tolerating at least 4 mg were kept on doxazosin. The majority of patients received the 8-mg dose over the duration of the study.

Long-Term Data

High-Grade Prostate Cancer:

The PCPT trial was a 7-year randomized, double-blind, placebo-controlled trial 18,882 men >55 years with a normal digital rectal examination and a PSA ≤3.0 ng/mL were enrolled. The men received either finasteride 5 mg or placebo daily. Patients were evaluated annually with PSA and digital rectal exams. Biopsies were performed for elevated PSA, an abnormal digital rectal exam, or the end of study. The incidence of Gleason score 8–10 prostate cancer was higher in men treated with finasteride (1.8%) than in those treated with placebo (1.1%). In a 4-year placebo-controlled clinical trial with another 5 alpha-reductase inhibitor (dutasteride), similar results for Gleason score 8–10 prostate cancer were observed (1% dutasteride vs 0.5% placebo).

No clinical benefit has been demonstrated in patients with prostate cancer treated with finasteride.

Breast Cancer:

During the 4- to 6-year placebo- and comparator-controlled study that enrolled 3,047 men, there were four cases of breast cancer in men treated with finasteride but no cases in men not treated with finasteride. During the 4-year placebo-controlled study that enrolled 3,040 men, there were two cases of breast cancer in placebo-treated men, but no cases were reported in men treated with finasteride. During the 7-year placebo-controlled Prostate Cancer Prevention Trial (PCPT) that enrolled 18,882 men, there was 1 case of breast cancer in men treated with finasteride, and 1 case of breast cancer in men treated with placebo. The relationship between long-term use of finasteride and male breast neoplasia is currently unknown.

Sexual Function:

There is no evidence of increased sexual adverse experiences with increased duration of treatment with finasteride. New reports of drug-related sexual adverse experiences decreased with duration of therapy.

Cytochrome P450-Linked Drug Metabolizing Enzyme System

No drug interactions of clinical importance have been identified. Finasteride does not appear to affect the cytochrome P450-linked drug metabolizing enzyme system. Compounds that have been tested in man have included antipyrine, digoxin, propranolol, theophylline, and warfarin and no clinically meaningful interactions were found.

Other Concomitant Therapy

Although specific interaction studies were not performed, finasteride was concomitantly used in clinical studies with acetaminophen, acetylsalicylic acid, alpha-blockers, angiotensin-converting enzyme (ACE) inhibitors, analgesics, anti-convulsants, beta-adrenergic blocking agents, diuretics, calcium channel blockers, cardiac nitrates, HMG-CoA reductase inhibitors, non-steroidal antiinflammatory drugs (NSAIDs), benzodiazepines, H2 antagonists and quinolone anti-infectives without evidence of clinically significant adverse interactions.

Pregnancy Category X.

FINCAR is contraindicated for use in women who are or may become pregnant. Finasteride is a Type II 5α-reductase inhibitor that prevents conversion of testosterone to 5α-dihydrotestosterone (DHT), a hormone necessary for normal development of male genitalia. In animal studies, finasteride caused abnormal development of external genitalia in male fetuses. If this drug is used during pregnancy, or if the patient becomes pregnant while taking this drug, the patient should be apprised of the potential hazard to the male fetus.

Abnormal male genital development is an expected consequence when conversion of testosterone to 5α-dihydrotestosterone (DHT) is inhibited by 5α-reductase inhibitors. These outcomes are similar to those reported in male infants with genetic 5α-reductase deficiency. Women could be exposed to finasteride through contact with crushed or broken finasteride tablets or semen from a male partner taking finasteride. With regard to finasteride exposure through the skin, finasteride tablets are coated and will prevent skin contact with finasteride during normal handling if the tablets have not been crushed or broken. Women who are pregnant or may become pregnant should not handle crushed or broken finasteride tablets because of possible exposure of a male fetus. If a pregnant woman comes in contact with crushed or broken finasteride tablets, the contact area should be washed immediately with soap and water. With regard to potential finasteride exposure through semen, two studies have been conducted in men receiving finasteride 5 mg/day that measured finasteride concentrations in semen.

In an embryo-fetal development study, pregnant rats received finasteride during the period of major organogenesis (gestation days 6 to 17). At maternal doses of oral finasteride approximately 0.1 to 86 times the maximum recommended human dose (MRHD) of 5 mg/day (based on AUC at animal doses of 0.1 to 100 mg/kg/day) there was a dose-dependent increase in hypospadias that occurred in 3.6 to 100% of male offspring. Exposure multiples were estimated using data from nonpregnant rats. Days 16 to 17 of gestation is a critical period in male fetal rats for differentiation of the external genitalia. At oral maternal doses approximately 0.03 times the MRHD (based on AUC at animal dose of 0.03 mg/kg/day), male offspring had decreased prostatic and seminal vesicular weights, delayed preputial separation and transient nipple development. Decreased anogenital distance occurred in male offspring of pregnant rats that received approximately 0.003 times the MRHD (based on AUC at animal dose of 0.003 mg/kg/day). No abnormalities were observed in female offspring at any maternal dose of finasteride.

No developmental abnormalities were observed in the offspring of untreated females mated with finasteride treated male rats that received approximately 61 times the MRHD (based on AUC at animal dose of 80 mg/kg/day). Slightly decreased fertility was observed in male offspring after administration of about 3 times the MRHD (based on AUC at animal dose of 3 mg/kg/day) to female rats during late gestation and lactation. No effects on fertility were seen in female offspring under these conditions.

No evidence of male external genital malformations or other abnormalities were observed in rabbit fetuses exposed to finasteride during the period of major organogenesis (gestation days 6-18) at maternal oral doses up to 100 mg/kg/day, (finasteride exposure levels were not measured in rabbits). However, this study may not have included the critical period for finasteride effects on development of male external genitalia in the rabbit.

The fetal effects of maternal finasteride exposure during the period of embryonic and fetal development were evaluated in the rhesus monkey (gestation days 20-100), in a species and development period more predictive of specific effects in humans than the studies in rats and rabbits. Intravenous administration of finasteride to pregnant monkeys at doses as high as 800 ng/day (estimated maximal blood concentration of 1.86 ng/mL or about 143 times the highest estimated exposure of pregnant women to finasteride from semen of men taking 5 mg/day) resulted in no abnormalities in male fetuses. In confirmation of the relevance of the rhesus model for human fetal development, oral administration of a dose of finasteride (2 mg/kg/day or approximately 18,000 times the highest estimated blood levels of finasteride from semen of men taking 5 mg/day) to pregnant monkeys resulted in external genital abnormalities in male fetuses. No other abnormalities were observed in male fetuses and no finasteride-related abnormalities were observed in female fetuses at any dose.

Finasteride is not indicated for use in women. It is not known whether finasteride is excreted in human milk.

Finasteride is not indicated for use in paediatric patients. Safety and effectiveness in paediatric patients have not been established.

Of the total number of subjects included in 4-Year Placebo-Controlled Study (PLESS), 1480 and 105 subjects were 65 and over and 75 and over, respectively. No overall differences in safety or effectiveness were observed between these subjects and younger subjects, and other reported clinical experience has not identified differences in responses between the elderly and younger patients. No dosage adjustment is necessary in the elderly.

No dosage adjustment is necessary in patients with renal impairment.

Caution should be used in the administration of finasteride in those patients with liver function abnormalities, as finasteride is metabolized extensively in the liver.