Balsalazide

12.1 Mechanism of Action Balsalazide disodium is delivered intact to the colon where it is cleaved by bacterial azoreduction to release equimolar quantities of mesalamine, which is the therapeutically active portion of the molecule, and the 4-aminobenzoyl-β-alanine carrier moiety. The carrier moiety released when balsalazide disodium is cleaved is only minimally absorbed and is largely inert. The mechanism of action of 5-ASA is not fully understood, but appears to be a local anti-inflammatory effect on colonic epithelial cells. Mucosal production of arachidonic acid metabolites, both through the cyclooxygenase pathways, i.e., prostanoids, and through the lipoxygenase pathways, i.e., leukotrienes and hydroxyeicosatetraenoic acids, is increased in patients with ulcerative colitis, and it is possible that 5-ASA diminishes inflammation by blocking production of arachidonic acid metabolites in the colon.

1 INDICATIONS AND USAGE Balsalazide disodium capsules are indicated for the treatment of mildly to moderately active ulcerative colitis in patients 5 years of age and older. Limitations of Use: Safety and effectiveness of balsalazide disodium capsules beyond 8 weeks in pediatric patients 5 years to 17 years of age and 12 weeks in adults have not been established. Balsalazide disodium capsules are an aminosalicylate indicated for the treatment of mildly to moderately active ulcerative colitis in patients 5 years of age and older. ( 1 ) Limitations of Use: Safety and effectiveness of balsalazide beyond 8 weeks in children (ages 5 to 17 years) and 12 weeks in adults have not been established. ( 1 )

2 DOSAGE AND ADMINISTRATION Administration Instructions: Evaluate renal function before initiating therapy with balsalazide disodium capsules. ( 2.1 ) Swallow capsules whole. Do not cut, break, crush or chew. ( 2.1 ) For patients who cannot swallow intact capsules, the capsules may be opened and sprinkled on applesauce, then chewed and swallowed immediately. ( 2.1 ) Teeth and/or tongue staining may occur when administered sprinkled on applesauce. ( 2.1 ) Drink an adequate amount of fluids. ( 2.1 , 5.8 ) Take balsalazide disodium capsules with or without food. ( 2.1 ) Dosage: Adults: The recommended dosage is 2.25 g (three 750 mg capsules) three times daily for 8 weeks. Some adult patients required treatment for up to 12 weeks in clinical trials. ( 2.2 ) Pediatric Patients 5 Years to 17 Years of Age: The recommended dosage is either : 2.25 g (three 750 mg capsules) three times for up to 8 weeks. OR: 750 mg (one capsule) three times daily for up to 8 weeks. ( 2.2 ) 2.1 Important Preparation and Administration Instructions Evaluate renal function before initiating therapy with balsalazide disodium capsules [see Warnings and Precaution ( 5.1 )] . Swallow balsalazide disodium capsules whole. Do not cut, break, crush or chew the capsules. For patients who cannot swallow intact capsules, balsalazide disodium capsules may also be administered by opening the capsule and sprinkling the capsule contents on applesauce. If the capsules are opened for sprinkling, color variation of the powder inside the capsules ranges from orange to yellow and is expected due to color variation of the active pharmaceutical ingredient. Place a small amount (approximately 10 mL) of applesauce into a clean container. Carefully open the capsules. Sprinkle the capsule contents on the applesauce. Mix the capsule contents with the applesauce. The contents may be chewed, if necessary. Consume the entire amount of applesauce mixture immediately. Do not store the applesauce mixture for future use. Teeth and/or tongue staining may occur in some patients when administered sprinkled on applesauce. Drink an adequate amount of fluids [see Warnings and Precautions ( 5.8 )] . Take balsalazide disodium capsules with or without food [see Clinical Pharmacology ( 12.3 )] . 2.2 Recommended Dosage in Adults and Pediatric Patients 5 Years to 17 Years of Age Adults: The recommended dosage in adults is 2.25 g (three 750 mg capsules) three times daily for up to 8 weeks. Some patients in the adult clinical trials required treatment for up to 12 weeks. Pediatric Patients 5 Years to 17 Years of Age: The recommended dosage in pediatric patients 5 years to 17 years of age is either : 2.25 g (three 750 mg capsules) three times daily for up to 8 weeks; OR: 750 mg (one capsule) three times daily for up to 8 weeks. Use of balsalazide disodium capsules in the pediatric population for more than 8 weeks has not been evaluated in clinical trials [see Clinical Studies ( 14 )] .

6 ADVERSE REACTIONS The following clinically significant adverse reactions are described elsewhere in labeling: Renal Impairment [see Warnings and Precautions ( 5.1 )] Mesalamine-Induced Acute Intolerance Syndrome [see Warnings and Precautions ( 5.2 )] Hypersensitivity Reactions [see Warnings and Precautions ( 5.3 )] Hepatic Failure [see Warnings and Precautions ( 5.4 )] Severe Cutaneous Adverse Reactions [see Warnings and Precautions ( 5.5 )] Upper Gastrointestinal Tract Obstruction [see Warnings and Precautions ( 5.6 )] Photosensitivity [see Warnings and Precautions ( 5.7 )] Nephrolithiasis [see Warnings and Precautions ( 5.8 )] Most common adverse reactions (≥3%) are: headache, abdominal pain, diarrhea, nausea, vomiting, respiratory infection, and arthralgia. Adverse reactions in pediatric patients were similar. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Hikma Pharmaceuticals USA Inc. at 1-800-962-8364 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. 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. Adult Ulcerative Colitis: During clinical development, 259 adult patients with active ulcerative colitis were exposed to 6.75 g/day balsalazide in 4 controlled trials. In the 4 controlled clinical trials patients receiving a balsalazide dose of 6.75 g/day most frequently reported the following adverse reactions: headache (8%), abdominal pain (6%), diarrhea (5%), nausea (5%), vomiting (4%), respiratory infection (4%), and arthralgia (4%). Withdrawal from therapy due to adverse reactions was comparable among patients on balsalazide and placebo. Adverse reactions reported by 1% or more of patients who participated in the 4 well-controlled, Phase 3 trials are presented by treatment group (Table 1). The number of placebo patients (35), however, is too small for valid comparisons. Some adverse reactions, such as abdominal pain, fatigue, and nausea were reported more frequently in women than in men. Abdominal pain, rectal bleeding, and anemia can be part of the clinical presentation of ulcerative colitis. Table 1: Adverse Reactions Occurring in ≥1% of Adult Balsalazide Patients in Controlled Trials Adverse reactions occurring in at least 1% of balsalazide patients which were less frequent than placebo for the same adverse reaction were not included in the table. Adverse Reaction Balsalazide 6.75 g/day [N=259] Placebo [N=35] Abdominal pain 16 (6%) 1 (3%) Diarrhea 14 (5%) 1 (3%) Arthralgia 9 (4%) 0% Rhinitis 6 (2%) 0% Insomnia 6 (2%) 0% Fatigue 6 (2%) 0% Flatulence 5 (2%) 0% Fever 5 (2%) 0% Dyspepsia 5 (2%) 0% Pharyngitis 4 (2%) 0% Coughing 4 (2%) 0% Anorexia 4 (2%) 0% Urinary tract infection 3 (1%) 0% Myalgia 3 (1%) 0% Flu-like disorder 3 (1%) 0% Dry mouth 3 (1%) 0% Cramps 3 (1%) 0% Constipation 3 (1%) 0% Pediatric Ulcerative Colitis: In a clinical trial in 68 pediatric patients aged 5 to 17 years with mildly to moderately active ulcerative colitis who received 6.75 g/day or 2.25 g/day balsalazide for 8 weeks, the most frequently reported adverse reactions were headache (15%), abdominal pain upper (13%), abdominal pain (12%), vomiting (10%), diarrhea (9%), colitis ulcerative (6%), nasopharyngitis (6%), and pyrexia (6%) [see Table 2 ] . One patient who received balsalazide 6.75 g/day and 3 patients who received balsalazide 2.25 g/day discontinued treatment because of adverse reactions. In addition, 2 patients in each dose group discontinued because of a lack of efficacy. Adverse reactions reported by 3% or more of pediatric patients within either treatment group in the Phase 3 trial are presented in Table 2. Table 2: Treatment-Emergent Adverse Reactions Reported by ≥3% of Patients in Either Treatment Group in a Controlled Study of 68 Pediatric Patients Balsalazide Adverse Reaction 6.75 g/day [N = 33] 2.25 g/day [N = 35] Total [N = 68] Headache 5 (15%) 5 (14%) 10 (15%) Abdominal pain upper 3 (9%) 6 (17%) 9 (13%) Abdominal pain 4 (12%) 4 (11%) 8 (12%) Vomiting 1 (3%) 6 (17%) 7 (10%) Diarrhea 2 (6%) 4 (11%) 6 (9%) Colitis ulcerative 2 (6%) 2 (6%) 4 (6%) Nasopharyngitis 3 (9%) 1 (3%) 4 (6%) Pyrexia 0 (0%) 4 (11%) 4 (6%) Hematochezia 0 (0%) 3 (9%) 3 (4%) Nausea 0 (0%) 3 (9%) 3 (4%) Influenza 1 (3%) 2 (6%) 3 (4%) Fatigue 2 (6%) 1 (3%) 3 (4%) Stomatitis 0 (0%) 2 (6%) 2 (3%) Cough 0 (0%) 2 (6%) 2 (3%) Pharyngolaryngeal pain 2 (6%) 0 (0%) 2 (3%) Dysmenorrhea 2 (6%) 0 (0%) 2 (3%) 6.2 Postmarketing Experience The following adverse reactions have been identified during post-approval use of balsalazide, or other products which contain or are metabolized to mesalamine. 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. Cardiovascu

7 DRUG INTERACTIONS Nephrotoxic Agents including NSAIDs : Increased risk of nephrotoxicity; monitor for changes in renal function and mesalamine-related adverse reactions. ( 7.1 ) Azathioprine or 6-Mercaptopurine : Increased risk of blood disorders; monitor complete blood cell counts and platelet counts. ( 7.2 ) 7.1 Nephrotoxic Agents, Including Non-Steroidal Anti-Inflammatory Drugs The concurrent use of mesalamine with known nephrotoxic agents, including non-steroidal anti-inflammatory drugs (NSAIDs), may increase the risk of renal reactions. Monitor patients taking nephrotoxic drugs for changes in renal function and mesalamine-related adverse reactions [see Warnings and Precautions ( 5.1 )] . 7.2 Azathioprine or 6-Mercaptopurine The concurrent use of mesalamine with azathioprine or 6-mercaptopurine and/or any other drugs known to cause myelotoxicity may increase the risk for blood disorders, bone marrow failure, and associated complications. If concomitant use of balsalazide disodium capsules and azathioprine or 6-mercaptopurine cannot be avoided, monitor blood tests, including complete blood cell counts and platelet counts. 7.3 Interference With Urinary Normetanephrine Measurements Use of balsalazide disodium capsules, which is converted to mesalamine, may lead to spuriously elevated test results when measuring urinary normetanephrine by liquid chromatography with electrochemical detection [see Warnings and Precautions ( 5.9 )] . Consider an alternative, selective assay for normetanephrine.