XENICAL Capsule Ref.[10625] Active ingredients: Orlistat

5.1 Drug Interactions and Decreased Vitamin Absorption

XENICAL may interact with concomitant drugs including cyclosporine, levothyroxine, warfarin, amiodarone, antiepileptic drugs, and antiretroviral drugs [see Drug Interactions (7)].

Data from a XENICAL and cyclosporine drug interaction study indicate a reduction in cyclosporine plasma levels when XENICAL was coadministered with cyclosporine. Therefore, XENICAL and cyclosporine should not be simultaneously coadministered. To reduce the chance of a drug-drug interaction, cyclosporine should be taken at least 3 hours before or after XENICAL in patients taking both drugs. In addition, in those patients whose cyclosporine levels are being measured, more frequent monitoring should be considered.

Patients should be strongly encouraged to take a multivitamin supplement that contains fat-soluble vitamins to ensure adequate nutrition because XENICAL has been shown to reduce the absorption of some fat-soluble vitamins and beta-carotene [see Dosage and Administration (2), and Adverse Reactions (6.1)]. In addition, the levels of vitamin D and beta-carotene may be low in obese patients compared with non-obese subjects. The supplement should be taken once a day at least 2 hours before or after the administration of XENICAL, such as at bedtime.

Weight-loss may affect glycemic control in patients with diabetes mellitus. A reduction in dose of oral hypoglycemic medication (e.g., sulfonylureas) or insulin may be required in some patients [see Clinical Studies (14)].

5.2 Liver Injury

There have been rare postmarketing reports of severe liver injury with hepatocellular necrosis or acute hepatic failure in patients treated with XENICAL, with some of these cases resulting in liver transplant or death. Patients should be instructed to report any symptoms of hepatic dysfunction (anorexia, pruritus, jaundice, dark urine, light-colored stools, or right upper quadrant pain) while taking XENICAL. When these symptoms occur, XENICAL and other suspect medications should be discontinued immediately and liver function tests and ALT and AST levels obtained.

5.3 Increases in Urinary Oxalate

Some patients may develop increased levels of urinary oxalate following treatment with XENICAL. Cases of oxalate nephrolithiasis and oxalate nephropathy with renal failure have been reported. Monitor renal function when prescribing XENICAL to patients at risk for renal impairment and use with caution in those with a history of hyperoxaluria or calcium oxalate nephrolithiasis.

5.4 Cholelithiasis

Substantial weight loss can increase the risk of cholelithiasis. In a clinical trial of XENICAL for the prevention of type 2 diabetes, the rates of cholelithiasis as an adverse event were 2.9% (47/1649) for patients randomized to XENICAL and 1.8% (30/1655) for patients randomized to placebo.

5.5 Miscellaneous

Organic causes of obesity (e.g., hypothyroidism) should be excluded before prescribing XENICAL.

Patients should be advised to adhere to dietary guidelines [see Dosage and Administration (2)]. Gastrointestinal events [see Adverse Reactions (6.1)] may increase when XENICAL is taken with a diet high in fat (>30% total daily calories from fat). The daily intake of fat should be distributed over three main meals. If XENICAL is taken with any one meal very high in fat, the possibility of gastrointestinal effects increases.

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

Commonly Observed (based on first year and second year data)

Gastrointestinal (GI) symptoms were the most commonly observed treatment-emergent adverse events associated with the use of XENICAL in the seven double-blind, placebo-controlled clinical trials and are primarily a manifestation of the mechanism of action. (Commonly observed is defined as an incidence of ≥5% and an incidence in the XENICAL 120 mg group that is at least twice that of placebo.)

Table 2. Commonly Observed Adverse Events:

^* Treatment designates XENICAL three times a day plus diet or placebo plus diet
^† Oily discharge may be clear or have a coloration such as orange or brown.

In general, the first occurrence of these events was within 3 months of starting therapy. Overall, approximately 50% of all episodes of GI adverse events associated with XENICAL treatment lasted for less than 1 week, and a majority lasted for no more than 4 weeks. However, GI adverse events may occur in some individuals over a period of 6 months or longer.

Discontinuation of Treatment

In controlled clinical trials, 8.8% of patients treated with XENICAL discontinued treatment due to adverse events, compared with 5.0% of placebo-treated patients. For XENICAL, the most common adverse events resulting in discontinuation of treatment were gastrointestinal.

Other Adverse Clinical Events

The following table lists other treatment-emergent adverse events from seven multicenter, double-blind, placebo-controlled clinical trials that occurred at a frequency of ≥2% among patients treated with XENICAL 120 mg three times a day and with an incidence that was greater than placebo during year 1 and year 2, regardless of relationship to study medication.

Table 3. Other Treatment-Emergent Adverse Events From Seven Placebo-Controlled Clinical Trials:

– None reported at a frequency ≥2% and greater than placebo
^* Treatment designates XENICAL 120 mg three times a day plus diet or placebo plus diet

Table 4 illustrates the percentage of adult patients on XENICAL and placebo who developed a low vitamin level on two or more consecutive visits during 1 and 2 years of therapy in studies in which patients were not previously receiving vitamin supplementation.

Table 4. Incidence of Low Vitamin Values on Two or More Consecutive Visits (Nonsupplemented Adult Patients With Normal Baseline Values – First and Second Year):

^* Treatment designates placebo plus diet or XENICAL plus diet

Table 5 illustrates the percentage of adolescent patients on XENICAL and placebo who developed a low vitamin level on two or more consecutive visits during the 1-year study.

Table 5. Incidence of Low Vitamin Values on Two or More Consecutive Visits (Pediatric Patients With Normal Baseline Values^*):

^* All patients were treated with vitamin supplementation throughout the course of the study
^† Treatment designates placebo plus diet or XENICAL plus diet

In the 4-year XENDOS study, the general pattern of adverse events was similar to that reported for the 1- and 2-year studies with the total incidence of gastrointestinal-related adverse events occurring in year 1 decreasing each year over the 4-year period.

In clinical trials in obese diabetic patients, hypoglycemia and abdominal distension were also observed.

Pediatric Patients

In clinical trials with XENICAL in adolescent patients ages 12 to 16 years, the profile of adverse reactions was generally similar to that observed in adults.

The following adverse reactions have been identified during postapproval use of XENICAL. 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 XENICAL exposure.

• Rare cases of increase in transaminases and in alkaline phosphatase and hepatitis that may be serious have been reported. There have been reports of hepatic failure observed with the use of XENICAL in postmarketing surveillance, with some of these cases resulting in liver transplant or death [see Warnings and Precautions (5.2)].
• Rare cases of hypersensitivity have been reported with the use of XENICAL. Signs and symptoms have included pruritus, rash, urticaria, angioedema, bronchospasm and anaphylaxis. Very rare cases of bullous eruption have been reported.
• Rare cases of leukocytoclastic vasculitis have been reported. Clinical signs include palpable purpura, maculopapular lesions, or bullous eruption.
• Acute oxalate nephropathy after treatment with XENICAL has been reported in patients with or at risk for renal disease [see Warnings and Precautions (5.3)].
• Pancreatitis has been reported with the use of XENICAL in postmarketing surveillance. No causal relationship or physiopathological mechanism between pancreatitis and obesity therapy has been definitively established.
• Lower gastrointestinal bleeding has been reported in patients treated with XENICAL. Most reports are nonserious; severe or persistent cases should be investigated further.

7.1 Cyclosporine

Data from a XENICAL and cyclosporine drug interaction study indicate a reduction in cyclosporine plasma levels when XENICAL was coadministered with cyclosporine. XENICAL and cyclosporine should not be simultaneously coadministered. Cyclosporine should be administered 3 hours after the administration of XENICAL [see Dosage and Administration (2), and Warnings and Precautions (5.1)].

7.2 Fat-soluble Vitamin Supplements and Analogues

Data from a pharmacokinetic interaction study showed that the absorption of beta-carotene supplement is reduced when concomitantly administered with XENICAL. XENICAL inhibited absorption of a vitamin E acetate supplement. The effect of XENICAL on the absorption of supplemental vitamin D, vitamin A, and nutritionally-derived vitamin K is not known at this time [see Clinical Pharmacology (12.3), and Warnings and Precautions (5.1)].

7.3 Levothyroxine

Hypothyroidism has been reported in patients treated concomitantly with XENICAL and levothyroxine postmarketing. Patients treated concomitantly with XENICAL and levothyroxine should be monitored for changes in thyroid function. Administer levothyroxine and XENICAL at least 4 hours apart [see Dosage and Administration (2)].

7.4 Anticoagulants including Warfarin

Vitamin K absorption may be decreased with XENICAL. Reports of decreased prothrombin, increased INR and unbalanced anticoagulant treatment resulting in change of hemostatic parameters have been reported in patients treated concomitantly with XENICAL and anticoagulants. Patients on chronic stable doses of warfarin or other anticoagulants who are prescribed XENICAL should be monitored closely for changes in coagulation parameters [see Clinical Pharmacology (12.3)].

7.5 Amiodarone

A pharmacokinetic study, where amiodarone was orally administered during orlistat treatment, demonstrated a reduction in exposure to amiodarone and its metabolite, desethylamiodarone [see Clinical Pharmocology (12.3)]. A reduced therapeutic effect of amiodarone is possible. The effect of commencing orlistat treatment in patients on stable amiodarone therapy has not been studied.

7.6 Antiepileptic Drugs

Convulsions have been reported in patients treated concomitantly with orlistat and antiepileptic drugs. Patients should be monitored for possible changes in the frequency and/or severity of convulsions.

7.7 Antiretroviral Drugs

Loss of virological control has been reported in HIV-infected patients taking orlistat concomitantly with antiretroviral drugs such as atazanavir, ritonavir, tenofovir disoproxil fumarate, emtricitabine, and with the combinations lopinavir/ritonavir and emtricitabine/efavirenz/tenofovir disoproxil fumarate. The exact mechanism for this is unclear, but may include a drug-drug interaction that inhibits systemic absorption of the antiretroviral drug. HIV RNA levels should be frequently monitored in patients who take XENICAL while being treated for HIV infection. If there is a confirmed increase in HIV viral load, XENICAL should be discontinued.

Pregnancy Category X

XENICAL is contraindicated during pregnancy, because weight loss offers no potential benefit to a pregnant woman and may result in fetal harm. A minimum weight gain, and no weight loss, is currently recommended for all pregnant women, including those who are already overweight or obese, due to the obligatory weight gain that occurs in maternal tissues during pregnancy. No embryotoxicity or teratogenicity was seen in animals that received orlistat at doses much higher than the recommended human dose. 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 of maternal weight loss to the fetus.

Animal Data

Reproduction studies were conducted in rats and rabbits at doses up to 800 mg/kg/day. Neither study showed embryotoxicity or teratogenicity. This dose is 23 and 47 times the daily human dose calculated on a body surface area (mg/m²) basis for rats and rabbits, respectively.

It is not known if XENICAL is present in human milk. Caution should be exercised when XENICAL is administered to a nursing woman.

Safety and effectiveness in pediatric patients below the age of 12 have not been established.

The safety and efficacy of XENICAL have been evaluated in obese adolescent patients aged 12 to 16 years. Use of XENICAL in this age group is supported by evidence from adequate and well-controlled studies of XENICAL in adults with additional data from a 54-week efficacy and safety study and a 21-day mineral balance study in obese adolescent patients aged 12 to 16 years. Patients treated with XENICAL in the 54-week efficacy and safety study (64.8% female, 75% Caucasians, 18.8% Blacks, and 6.3% Other) had a mean reduction in BMI of 0.55 kg/m² compared with an average increase of 0.31 kg/m² in placebo-treated patients (p=0.001). In both adolescent studies, adverse effects were generally similar to those described in adults and included fatty/oily stool, oily spotting, and oily evacuation. In a subgroup of 152 XENICAL and 77 placebo patients from the 54-week study, changes in body composition measured by DEXA were similar in both treatment groups with the exception of fat mass, which was significantly reduced in patients treated with XENICAL compared to patients treated with placebo (-2.5 kg vs -0.6 kg, p=0.033). Because XENICAL can interfere with the absorption of fat-soluble vitamins, all patients should take a daily multivitamin that contains vitamins A, D, E, K, and beta-carotene. The vitamin supplement should be taken at least 2 hours before or after XENICAL [see Dosage and Administration (2), Warnings and Precautions (5.1), and Clinical Pharmacology (12.3)] .

Plasma concentrations of orlistat and its metabolites M1 and M3 were similar to those found in adults at the same dose level. Daily fecal fat excretions were 27% and 7% of dietary intake in XENICAL and placebo treatment groups, respectively.

Clinical studies of XENICAL did not include sufficient numbers of patients aged 65 years and older to determine whether they respond differently from younger patients [see Clinical Studies (14)].

As with any weight-loss agent, the potential exists for abuse of XENICAL in inappropriate patient populations (e.g., patients with anorexia nervosa or bulimia). See Indications and Usage (1) for recommended prescribing guidelines.