Risedronate Sodium

1 INDICATIONS AND USAGE Risedronate sodium delayed-release tablets are bisphosphonate in a delayed-release formulation and is indicated for treatment of postmenopausal osteoporosis (1.1) Limitations of Use Optimal duration of use has not been determined. For patients at low-risk for fracture, consider drug discontinuation after 3 to 5 years of use (1.2). 1.1 Postmenopausal Osteoporosis Risedronate sodium delayed-release tablets are indicated for the treatment of osteoporosis in postmenopausal women. In postmenopausal women, risedronate sodium has been shown to reduce the incidence of vertebral fractures and a composite endpoint of nonvertebral osteoporosis-related fractures [ see Clinical Studies (14.1) ]. 1.2 Important Limitations of Use The optimal duration of use has not been determined. The safety and effectiveness of risedronate sodium delayed-release tablets for the treatment of osteoporosis are based on clinical data of one year duration. All patients on bisphosphonate therapy should have the need for continued therapy re-evaluated on a periodic basis. Patients at low-risk for fracture should be considered for drug discontinuation after 3 to 5 years of use. Patients who discontinue therapy should have their risk for fracture re-evaluated periodically.

2 DOSAGE AND ADMINISTRATION One 35 mg delayed-release tablet once-a-week (2.1) Instruct patients to: • Take risedronate sodium delayed-release tablets in the morning immediately following breakfast with at least 4 ounces of plain water (2.2) • Avoid lying down for 30 minutes after taking risedronate sodium delayed-release tablets (2.2) • Take supplemental calcium and vitamin D if dietary intake is inadequate (2.3) 2.1 Treatment of Postmenopausal Osteoporosis [ see Indications and Usage (1.1) ] The recommended regimen is: • one 35 mg delayed-release tablet orally, taken once-a-week [see Indications and Usage (1.1)] 2.2 Important Administration Instructions Instruct patients to do the following: • Take risedronate sodium delayed-release tablets in the morning immediately following breakfast. Risedronate sodium delayed-release tablets should be taken immediately following breakfast and not under fasting conditions because of a higher risk of abdominal pain if taken before breakfast when fasting. • Swallow risedronate sodium delayed-release tablets whole while in an upright position and with at least 4 ounces of plain water to facilitate delivery to the stomach. Avoid lying down for 30 minutes after taking the medication [ see Warnings and Precautions (5.2) ]. • Do not chew, cut, or crush risedronate sodium delayed-release tablets. 2.3 Recommendations for Calcium and Vitamin D Supplementation Instruct patients to take supplemental calcium and vitamin D if dietary intake is inadequate [ see Warnings and Precautions (5.3) ] and to take calcium supplements, antacids, magnesium-based supplements or laxatives, and iron preparations at a different time of the day as they interfere with the absorption of risedronate sodium delayed-release tablets. 2.4 Administration Instructions for Missed Doses If the once-weekly dose is missed, instruct patients to take one tablet on the morning after they remember and return to taking one tablet once-a-week, as originally scheduled on their chosen day. Patients should not take two tablets on the same day.

6 ADVERSE REACTIONS Most common adverse reactions (greater than 5%) include: diarrhea, influenza, arthralgia, back pain, and abdominal pain (6.1) Hypersensitivity reactions (angioedema, generalized rash, bullous skin reactions, Stevens-Johnson syndrome, and toxic epidermal necrolysis), and eye inflammation (iritis, uveitis) have been reported rarely (6.2) To report SUSPECTED ADVERSE REACTIONS, contact Sun Pharmaceutical Industries Inc. at 1-800-818-4555 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. 6.1 Clinical Studies 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 to rates in the clinical trials of another drug and may not reflect the rates observed in practice. Treatment of Postmenopausal Osteoporosis Once-a-Week Dosing with Risedronate Sodium Delayed-Release tablets The safety of risedronate sodium delayed-release 35 mg once-a-week in the treatment of postmenopausal osteoporosis was assessed in a 1-year, double-blind, multicenter study comparing risedronate sodium delayed-release 35 mg once-a-week to risedronate sodium immediate-release 5 mg daily in postmenopausal women 50 years of age or older. Risedronate sodium delayed-release was administered either at least 30 minutes before (N = 308) or immediately following (N = 307) breakfast, and risedronate sodium immediate-release 5 mg daily (N = 307) was administered at least 30 minutes before breakfast. Patients with pre-existing gastrointestinal disease and concomitant use of non-steroidal anti-inflammatory drugs, proton pump inhibitors, and H 2 antagonists were included in this clinical trial. All women received daily supplementation with 1000 mg of elemental calcium plus 800 to 1000 international units vitamin D. As treatment with risedronate sodium resulted in a significantly higher incidence of abdominal pain when administered before breakfast under fasting conditions, safety results that follow refer only to risedronate sodium delayed-release 35 mg once-a-week immediately following breakfast and risedronate sodium immediate-release 5 mg daily. The incidence of all-cause mortality was 0.0% in the risedronate sodium delayed-release 35 mg once-a-week group and 0.3% in the risedronate sodium immediate-release 5 mg daily group. The incidence of serious adverse reactions was 6.5% in the risedronate sodium delayed-release 35 mg once-a-week group and 7.2% in the risedronate sodium immediate-release 5 mg daily group. The percentage of patients who withdrew from the study due to adverse reactions was 9.1% in the risedronate sodium delayed-release 35 mg once-a-week group and 8.1% in the risedronate sodium immediate-release 5 mg daily group. The overall safety and tolerability profiles of the two dosing regimens were similar. Table 1 lists adverse reactions reported in greater than or equal to 2% of patients. Adverse reactions are shown without attribution of causality. Table 1 Adverse Reactions Occurring at a Frequency of greater than or equal to 2% in Either Treatment Group System Organ Class Preferred Term 35 mg Risedronate sodium Delayed-release Weekly N = 307% 5 mg Risedronate sodium Immediate-release Daily N = 307% Gastrointestinal disorders Diarrhea 8.8 4.9 Abdominal pain 5.2 2.9 Constipation 4.9 2.9 Vomiting 4.9 1.6 Dyspepsia 3.9 3.9 Nausea 3.6 3.9 Abdominal pain upper 2.9 2.3 Infections and infestations Influenza 7.2 6.2 Bronchitis 3.9 4.2 Upper respiratory tract infection 3.6 2.6 Musculoskeletal and connective tissue disorders Arthralgia 6.8 7.8 Back pain 6.8 5.9 Pain in extremity 3.9 2.3 Musculoskeletal pain 2.0 1.6 Muscle spasms 1.0 2.3 Nervous system disorders Dizziness 2.6 3.3 Headache 2.6 4.9 Acute Phase Reactions: Symptoms consistent with acute phase reaction have been reported with bisphosphonate use. The overall incidence of acute phase reaction was 2.3% in the risedronate sodium delayed-release 35 mg once-a-week group and 1.3% in the risedronate sodium immediate-release 5 mg daily group. These incidence rates are based on reporting of one or more pre-specified acute phase reaction-like symptoms within 3 days of the first dose and for a duration of 7 days or less. Gastrointestinal Adverse Reactions : Adverse reactions related to the upper gastrointestinal tract occurred in 16% of subjects treated with risedronate sodium delayed-release 35 mg once-a-week and 15% of subjects treated with risedronate sodium immediate-release 5 mg daily. The incidence of upper gastrointestinal tract adverse reactions in the risedronate sodium delayed-release 35 mg once-a-week and risedronate sodium immediate-release 5 mg daily groups were: abdominal pain (5.2% versus 2.9%), dyspepsia (3.9% versus 3.9%), upper abdominal pain (2.9% versus 2.3%), gastritis (1.0% versus 1.0%), and gastroesophageal reflux disease (1.0% versus 1.6%). Study discontinuation due to abdominal pain occurred in 1.3% of the risedronate sodium delayed-release 35 mg once-a-week group and 0.7% of the risedronate sodium immediate-release 5 mg daily group. Musculoskeletal Adverse Reactions: Selected musculoskeletal adverse reactions were reported in 16% of subjects treated with risedronate sodium delayed-release 35 mg once-a-week and 15% of subjects treated with risedronate sodium immediate-release 5 mg daily. The incidence of musculoskeletal adverse reactions in the risedronate sodium delayed-release 35 mg once-a-week and risedronate sodium immediate-release 5 mg daily groups were: arthralgia (6.8% versus 7.8%), back pain (6.8% versus 5.9%), musculoskeletal pain (2.0% versus 1.6%), and myalgia (1.3% versus 1.0%). Laboratory Test Findings : Parathyroid hormone: The effect of risedronate sodium delayed-release 35 mg once-a-week and risedronate sodium immediate-release 5 mg daily on parathyroid hormone was evaluated in postmenopausal women with osteoporosis. At week 52, in subjects with normal levels at baseline, PTH levels greater than 65 pg/mL (upper limit of normal) were noted in 9% of subjects receiving risedronate sodium delayed-release 35 mg once-a-week and 8% of subjects receiving risedronate sodium immediate-release 5 mg daily. In subjects with normal levels at baseline, PTH levels greater than 97 pg/mL (1.5 times the upper limit of normal) were seen in 2% of subjects receiving risedronate sodium delayed-release 35 mg once-a-week and no subjects receiving risedronate sodium immediate-release 5 mg daily. There were no clinically significant differences between treatment groups for levels of calcium, phosphorus and magnesium. Daily Dosing with Risedronate Sodium Immediate-Release 5 mg tablets The safety of risedronate sodium immediate-release 5 mg once daily in the treatment of postmenopausal osteoporosis was assessed in four randomized, double-blind, placebo-controlled multinational trials of 3232 women aged 38 to 85 years with postmenopausal osteoporosis. The duration of the trials was up to three years, with 1619 patients exposed to placebo and 1613 patients exposed to risedronate sodium immediate-release 5 mg daily. Patients with pre-existing gastrointestinal disease and concomitant use of non-steroidal anti-inflammatory drugs, proton pump inhibitors (PPIs), and H 2 antagonists were included in these clinical trials. All women received 1000 mg of elemental calcium plus vitamin D supplementation up to 500 international units per day if their 25-hydroxyvitamin D 3 level was below normal at baseline. The incidence of all-cause mortality was 2.0% in the placebo group and 1.7% in the risedronate sodium immediate-release 5 mg daily group. The incidence of serious adverse reactions was 24.6% in the placebo group and 27.2% in the risedronate sodium immediate-release 5 mg daily group. The percentage of patients who withdrew from the study due to adverse reactions was 15.6% in the placebo group and 14.8% in the risedronate sodium immediate-release 5 mg daily group. The most common adverse reactions reported in greater than 10% of subjects were: back pain, arthralgia, abdominal pain and dyspepsia. Gastrointestinal Adverse Reactions: The incidence of adverse reactions in the placebo and risedronate sodium immediate-release 5 mg daily groups were: abdominal pain (9.9% versus 12.2%), diarrhea (10.0% versus 10.8%), dyspepsia (10.6% versus 10.8%), and gastritis (2.3% versus 2.7%). Duodenitis and glossitis have been reported uncommonly in the risedronate sodium immediate-release 5 mg daily group (0.1% to 1%). In patients with active upper gastrointestinal disease at baseline, the incidence of upper gastrointestinal adverse reactions was similar between the placebo and risedronate sodium immediate-release 5 mg daily groups. Musculoskeletal Adverse Reactions: The incidence of adverse reactions in the placebo and risedronate sodium immediate-release 5 mg daily groups were: back pain (26.1% versus 28.0%), arthralgia (22.1% versus 23.7%), myalgia (6.2% versus 6.7%), and bone pain (4.8% versus 5.3%). Laboratory Test Findings : Throughout the Phase 3 studies, transient decreases from baseline in serum calcium (less than 1%) and serum phosphate (less than 3%) and compensatory increases in serum PTH levels (less than 30%) were observed within 6 months in patients in osteoporosis clinical trials treated with risedronate sodium immediate-release 5 mg daily. There were no significant differences in serum calcium, phosphate, or PTH levels between placebo and risedronate sodium immediate-release 5 mg daily at 3 years. Serum calcium levels below 8 mg/dL were observed in 18 patients, 9 (0.5%) in each treatment arm (placebo and risedronate sodium immediate-release 5 mg daily). Serum phosphorus levels below 2 mg/dL were observed in 14 patients, 3 (0.2%) treated with placebo and 11 (0.6%) treated with risedronate sodium immediate-release 5 mg daily. There have been rare reports (less than 0.1%) of abnormal liver function tests. Endoscopic Findings : In the risedronate sodium immediate-release 5 mg daily clinical trials, endoscopic evaluation was encouraged in any patient with moderate-to-severe gastrointestinal complaints, while maintaining the blind. Endoscopies were performed on equal numbers of patients between the placebo and treated groups [75 (14.5%) placebo; 75 (11.9%) risedronate sodium immediate-release 5 mg daily]. Clinically important findings (perforations, ulcers, or bleeding) among this symptomatic population were similar between groups (51% placebo; 39% risedronate sodium immediate-release 5 mg daily). 6.2 Postmarketing Experience The following adverse reactions have been reported with the use of risedronate sodium immediate-release. Because these adverse 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. Hypersensitivity Reactions Hypersensitivity and skin reactions have been reported, including angioedema, generalized rash, bullous skin reactions, Stevens-Johnson syndrome and toxic epidermal necrolysis. Gastrointestinal Adverse Reactions Reactions involving upper gastrointestinal irritation, such as esophagitis and esophageal or gastric ulcers, have been reported [ see Warnings and Precautions (5.2) ]. Musculoskeletal Pain Bone, joint, or muscle pain, described as severe or incapacitating, have been reported rarely [ see Warnings and Precautions (5.5) ]. Eye Inflammation Reactions of eye inflammation including iritis and uveitis have been reported rarely. Jaw Osteonecrosis Osteonecrosis of the jaw has been reported rarely [ see Warnings and Precautions (5.4) ]. Pulmonary Asthma exacerbations

12.3 Pharmacokinetics Absorption The mean absolute oral bioavailability of the 30 mg risedronate sodium immediate-release tablet taken 4 hours prior to a meal is 0.63% (90% confidence interval [CI]: 0.54% to 0.75%) and is similar to an oral solution. The time to peak concentration (T max ) for risedronate sodium delayed-release tablet is approximately 3 hours when administered in the morning 4 hours prior to a meal. Food Effect In a crossover pharmacokinetic study, the bioavailability of risedronate sodium 35 mg delayed-release tablets decreased by approximately 30% when administered immediately after a high-fat breakfast compared to administration in the morning 4 hours before a meal. The bioavailability of the 35 mg risedronate sodium delayed-release tablet administered after a high-fat breakfast was similar to risedronate sodium 35 mg immediate-release tablet dosed 4 hours before a meal in one study and was approximately 2- to 4-fold greater than the immediate-release 35 mg tablet administered 30 minutes prior to a high-fat breakfast. In a separate study, risedronate sodium administered after dinner exhibited approximately 87% increase in risedronate exposure compared to administration following a breakfast. The safety and efficacy of dosing risedronate sodium after dinner has not been evaluated [ see Dosage and Administration (2) ]. Distribution The mean steady-state volume of distribution for risedronate is 13.8 L/kg in humans. Human plasma protein binding of drug is about 24%. Preclinical studies in rats and dogs dosed intravenously with single doses of [ 14 C] risedronate indicate that approximately 60% of the dose is distributed to bone. The remainder of the dose is excreted in the urine. After multiple oral dosing in rats, the uptake of risedronate in soft tissues was in the range of 0.001% to 0.01%. Metabolism There is no evidence of systemic metabolism of risedronate. Excretion In young healthy subjects, approximately half of the absorbed dose of risedronate was excreted in urine within 24 hours, and 85% of an intravenous dose was recovered in the urine over 28 days. Based on simultaneous modeling of serum and urine data for the risedronate sodium immediate-release tablets, mean renal clearance was 105 mL/min (CV = 34%) and mean total clearance was 122 mL/min (CV = 19%), with the difference primarily reflecting nonrenal clearance or clearance due to adsorption to bone. The renal clearance is not concentration dependent, and there is a linear relationship between renal clearance and creatinine clearance. Unabsorbed drug is eliminated unchanged in feces. In osteopenic postmenopausal women, the terminal exponential half-life was 561 hours, mean renal clearance was 52 mL/min (CV = 25%), and mean total clearance was 73 mL/min (CV = 15%). Specific Populations Pediatric: Risedronate sodium is not indicated for use in pediatric patients [ see Pediatric Use (8.4) ]. Geriatric: Effect of age on bioavailability of risedronate sodium delayed-release has not been evaluated. Based on data from risedronate immediate-release tablet, bioavailability and disposition of risedronate are similar in elderly (greater than 60 years of age) and younger subjects. No dosage adjustment is necessary. Race: Pharmacokinetic differences due to race have not been studied. The clinical trial of risedronate sodium was conducted mostly in Caucasians. Renal Impairment: Risedronate is excreted unchanged primarily via the kidney. As compared to persons with normal renal function, the renal clearance of risedronate was decreased by about 70% in patients with creatinine clearance of approximately 30 mL/min. Risedronate sodium is not recommended for use in patients with severe renal impairment (creatinine clearance less than 30 mL/min). No dosage adjustment is necessary in patients with a creatinine clearance greater than or equal to 30 mL/min. Hepatic Impairment: No studies have been performed to assess risedronate’s safety or efficacy in patients with hepatic impairment. Risedronate is not metabolized in rat, dog, and human liver preparations. Insignificant amounts (less than 0.1% of intravenous dose) of drug are excreted in the bile in rats. Therefore, dosage adjustment is unlikely to be needed in patients with hepatic impairment. Drug Interactions: Risedronate is not metabolized and does not induce or inhibit hepatic microsomal drug-metabolizing enzymes (for example, Cytochrome P450). Calcium supplement: A Phase 1 single-dose, cross-over study in 101 postmenopausal women evaluated the relative bioavailability of risedronate sodium 35 mg delayed-release tablets taken after breakfast and following a 600 mg elemental calcium/400 international units vitamin D supplement, compared to risedronate sodium alone taken after breakfast without calcium or vitamin D supplementation. The addition of the calcium/vitamin D supplement following the meal resulted in an approximate 38% reduction in the amount of risedronate absorbed [ see Drug Interactions (7) ]. Proton Pump Inhibitors: A Phase 1, 2-period, cross-over study in 60 healthy postmenopausal female subjects evaluated the relative bioavailability of a single dose risedronate sodium 35 mg delayed-release tablet taken after breakfast following 6 days of esomeprazole magnesium delayed release 40 mg capsules. On Day 6, esomeprazole 40 mg capsule was administered with 240 mL water one hour before breakfast and risedronate sodium 35 mg tablet was administered with 240 mL water within 10 minutes after a standard breakfast. The C max and AUC inf of risedronate were increased by 60 percent and 22 percent, respectively, in presence of esomeprazole.