ADVERSE REACTIONS SECTION

Highlight: The most common adverse reactions (greater than 5%) are back pain, dyspepsia, pain in extremity, diarrhea, headache, and myalgia. (6)

To report SUSPECTED ADVERSE REACTIONS, contact Apotex Corp. at 1-800-706-5575 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.

6 ADVERSE REACTIONS

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 to rates in the clinical trials of another drug and may not reflect the rates observed in practice.

Treatment and Prevention of Postmenopausal Osteoporosis

Daily Dosing

The safety of ibandronate sodium tablets 2.5 mg once daily in the treatment and prevention of postmenopausal osteoporosis was assessed in 3577 patients aged 41 – 82 years. The duration of the trials was 2 to 3 years, with 1134 patients exposed to placebo and 1140 exposed to ibandronate sodium tablets 2.5 mg. Patients with pre-existing gastrointestinal disease and concomitant use of non-steroidal anti-inflammatory drugs, proton pump inhibitors and H2 antagonists were included in these clinical trials. All patients received 500 mg calcium plus 400 international units vitamin D supplementation daily.

The incidence of all-cause mortality was 1% in the placebo group and 1.2% in the ibandronate sodium tablets 2.5 mg daily group. The incidence of serious adverse reactions was 20% in the placebo group and 23% in the ibandronate sodium tablets 2.5 mg daily group. The percentage of patients who withdrew from treatment due to adverse reactions was approximately 17% in both the ibandronate sodium tablets 2.5 mg daily group and the placebo group. Table 1 lists adverse reactions from the treatment and prevention studies reported in greater than or equal to 2% of patients and more frequently in patients treated daily with ibandronate sodium tablets than patients treated with placebo.

Table 1 Adverse Reactions Occurring at an Incidence Greater Than or Equal to 2% and in More Patients Treated with Ibandronate Sodium Tablets Than in Patients Treated with Placebo Daily in the Osteoporosis Treatment and Prevention Studies

Gastrointestinal Adverse Reactions

The incidence of selected gastrointestinal adverse reactions in the placebo and ibandronate sodium tablets 2.5 mg daily groups were: dyspepsia (10% vs. 12%), diarrhea (5% vs. 7%), and abdominal pain (5% vs. 6%).

Musculoskeletal Adverse Reactions

The incidence of selected musculoskeletal adverse reactions in the placebo and ibandronate sodium tablets 2.5 mg daily groups were: back pain (12% vs. 14%), arthralgia (14% vs. 14%) and myalgia (5% vs. 6%).

Ocular Adverse Events

Reports in the medical literature indicate that bisphosphonates may be associated with ocular inflammation such as iritis and scleritis. In some cases, these events did not resolve until the bisphosphonate was discontinued. There were no reports of ocular inflammation in studies with ibandronate sodium tablets 2.5 mg daily.

Monthly Dosing

The safety of ibandronate sodium tablets 150 mg once monthly in the treatment of postmenopausal osteoporosis was assessed in a two year trial which enrolled 1583 patients aged 54 to 81 years, with 395 patients exposed to ibandronate sodium tablets 2.5 mg daily and 396 exposed to ibandronate sodium tablets 150 mg monthly. Patients with active or significant pre-existing gastrointestinal disease were excluded from this trial. Patients with dyspepsia or concomitant use of non-steroidal anti-inflammatory drugs, proton pump inhibitors and H2 antagonists were included in this study. All patients received 500 mg calcium plus 400 international units vitamin D supplementation daily.

After one year, the incidence of all-cause mortality was 0.3% in both the ibandronate sodium tablets 2.5 mg daily group and the ibandronate sodium tablets 150 mg monthly group. The incidence of serious adverse events was 5% in the ibandronate sodium tablets 2.5 mg daily group and 7% in the ibandronate sodium tablets 150 mg monthly group. The percentage of patients who withdrew from treatment due to adverse events was 9% in the ibandronate sodium tablets 2.5 mg daily group and 8% in the ibandronate sodium tablets 150 mg monthly group. Table 2 lists the adverse events reported in greater than or equal to 2% of patients.

Table 2 Adverse Events with an Incidence of at Least 2% in Patients Treated with Ibandronate Sodium Tablets 2.5 mg Daily or 150 mg Once-Monthly for Treatment of Postmenopausal Osteoporosis

a Combination of abdominal pain and abdominal pain upper

b Combination of influenza-like illness and acute phase reaction

c Combination of rash pruritic, rash macular, rash papular, rash generalized, rash erythematous, dermatitis, dermatitis allergic, dermatitis medicamentosa, erythema and exanthema

Gastrointestinal Adverse Events

The incidence of adverse events in the ibandronate sodium tablets 2.5 mg daily and ibandronate sodium tablets 150 mg monthly groups were: dyspepsia (7% vs. 6%), diarrhea (4% vs. 5%), and abdominal pain (5% vs. 8%).

Musculoskeletal Adverse Events

The incidence of adverse events in the ibandronate sodium tablets 2.5 mg daily and ibandronate sodium tablets 150 mg monthly groups were: back pain (4% vs. 5%), arthralgia (4% vs. 6%) and myalgia (1% vs. 2%).

Acute Phase Reactions

Symptoms consistent with acute phase reactions have been reported with bisphosphonate use. Over the two years of the study, the overall incidence of acute phase reaction symptoms was 3% in the ibandronate sodium tablets 2.5 mg daily group and 9% in the ibandronate sodium tablets 150 mg monthly group. These incidence rates are based on the reporting of any of 33 acute-phase reaction like symptoms within 3 days of the monthly dosing and lasting 7 days or less. Influenza like illness was reported in no patients in the ibandronate sodium tablets 2.5 mg daily group and 2% in the ibandronate sodium tablets 150 mg monthly group.

Ocular Adverse Events

Two patients who received ibandronate sodium tablets 150 mg once-monthly experienced ocular inflammation, one was a case of uveitis and the other scleritis.

One hundred sixty (160) postmenopausal women without osteoporosis participated in a 1-year, double-blind, placebo-controlled study of ibandronate sodium tablets 150 mg once-monthly for prevention of bone loss. Seventy-seven subjects received ibandronate sodium tablets and 83 subjects received placebo. The overall pattern of adverse events was similar to that previously observed.

6.2 Postmarketing Experience

The following adverse reactions have been identified during postapproval use of ibandronate sodium tablets. 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.

Hypersensitivity

Allergic reactions including anaphylactic reaction/shock with fatalities, angioedema, bronchospasm, asthma exacerbations, rash, Stevens-Johnson syndrome, erythema multiforme, and dermatitis bullous have been reported (see CONTRAINDICATIONS [4]).

Hypocalcemia

Hypocalcemia has been reported in patients treated with ibandronate sodium tablets (see WARNINGS AND PRECAUTIONS [5.2]).

Musculoskeletal Pain

Bone, joint, or muscle pain (musculoskeletal pain), described as severe or incapacitating, has been reported (see WARNINGS AND PRECAUTIONS [5.3]).

Jaw Osteonecrosis

Osteonecrosis of the jaw and other oro-facial sites, including the external auditory canal, have been reported in patients treated with ibandronate sodium tablets (see WARNINGS AND PRECAUTIONS [5.4]).

Atypical Femoral Shaft Fracture

Atypical, low-energy, or low-trauma fractures of the femoral shaft (see WARNINGS AND PRECAUTIONS [5.5]).

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