Mesalamine

ROWASA is indicated for the treatment of active mild to moderate distal ulcerative colitis, proctosigmoiditis or proctitis in adults. ROWASA is an aminosalicylate indicated for treatment of active mild to moderate distal ulcerative colitis, proctosigmoiditis or proctitis in adults. ( 1 )

Rectal Suspension: 4 g/60 mL enema bottle; off-white to tan colored suspension Rectal Suspension: 4 g/60 mL enema bottle ( 3 )

ROWASA is contraindicated in patients with known or suspected hypersensitivity to salicylates, aminosalicylates, sulfites or any other component of this medication [see Warnings and Precautions (5.3) ] . Known or suspected hypersensitivity to salicylates, aminosalicylates, sulfites or any other of the ingredients in ROWASA. ( 4 , 5.1 )

• Hypersensitivity Reactions : Sulfite-related reactions (ROWASA contains potassium metabisulfite) and sulfasalazine-associated reactions (myocarditis and pericarditis) can occur; evaluate patients immediately and discontinue ROWASA if a hypersensitivity reaction is suspected. ( 5.3 )
• Renal Impairment : Assess renal function at the beginning of treatment and periodically during treatment. Evaluate the risks and benefits of ROWASA in patients with known renal impairment or taking nephrotoxic drug. Discontinue ROWASA if renal function deteriorates while on therapy. ( 5.1 , 7.1 )
• Mesalamine-Induced Acute Intolerance Syndrome : Discontinue treatment if acute intolerance syndrome (cramping, acute abdominal pain, bloody diarrhea, sometimes fever, headache and rash) is suspected. ( 5.2 )
• Hepatic Failure : Evaluate the risks and benefits of using ROWASA in patients with known liver impairment. ( 5.4 )
• Severe Cutaneous Adverse Reactions : Discontinue at the first signs or symptoms of severe cutaneous adverse reactions or other signs of hypersensitivity and consider further evaluation. ( 5.5 )
• Photosensitivity : Avoid sun exposure if pre-existing skin conditions. ( 5.6 )
• Nephrolithiasis : Cases of nephrolithiasis have been reported with the use of mesalamine. Mesalamine-containing stones are undetectable by standard radiography or computed tomography (CT). Ensure adequate hydration during treatment. ( 5.7 )
• Interference with Laboratory Tests : Mesalamine may lead to elevated urinary normetanephrine test results. ( 5.8 )
• Intracranial Hypertension : If an unusual headache or visual disturbance occurs during treatment, immediately discontinue treatment and refer patient for further evaluation. ( 5.9 )

5.1 Hypersensitivity Reactions Sulfite-Related Reactions ROWASA contains potassium metabisulfite, a sulfite that may cause allergic-type reactions including anaphylactic symptoms and life-threatening or less severe asthmatic episodes in certain susceptible people. The overall prevalence of sulfite sensitivity in the general population is unknown but probably low. Sulfite sensitivity is seen more frequently in asthmatic or in atopic nonasthmatic persons. Epinephrine is the preferred treatment for serious allergic or emergency situations even though epinephrine injection contains sodium or potassium metabisulfite with the above-mentioned potential liabilities. The alternatives to using epinephrine in a life-threatening situation may not be satisfactory. The presence of a sulfite(s) in epinephrine injection should not deter the administration of the drug for treatment of serious allergic or other emergency situations. Sulfasalazine-Associated Reactions Hypersensitivity reactions have been reported in patients taking sulfasalazine. Some patients may have a similar reaction to ROWASA or to other compounds that contain or are converted to mesalamine. As with sulfasalazine, mesalamine-induced hypersensitivity reactions may present as internal organ involvement, including myocarditis, pericarditis, nephritis, hepatitis, pneumonitis and hematologic abnormalities. Evaluate patients immediately if signs or symptoms of a hypersensitivity reaction are present. Discontinue ROWASA if an alternative etiology for the signs and symptoms cannot be established.

5.2 Renal Impairment Renal impairment, including minimal change disease, acute and chronic interstitial nephritis, and renal failure have been reported in patients given ROWASA or other products that contain mesalamine or are converted to mesalamine. In animal studies, the kidney was the principal organ of mesalamine toxicity [see Nonclinical Toxicology (13.2) ] . Evaluate the risks and benefits of using ROWASA in patients with known renal impairment or a history of renal disease or taking concomitant nephrotoxic drugs. Evaluate renal function in all patients prior to initiation and periodically while on ROWASA therapy. Discontinue ROWASA if renal function deteriorates while on therapy [see Drug Interactions (7.1) , Use in Specific Populations (8.6) ] .

5.3 Mesalamine-Induced Acute Intolerance Syndrome Mesalamine has been associated with an acute intolerance syndrome that may be difficult to distinguish from a flare of inflammatory bowel disease. Although the exact frequency of occurrence cannot be ascertained, it has occurred in 3% of patients in controlled clinical trials of mesalamine or sulfasalazine. Symptoms include cramping, acute abdominal pain and bloody diarrhea, sometimes fever, headache, and rash. Monitor patients for worsening of these symptoms while on treatment. If acute intolerance syndrome is suspected, promptly discontinue treatment with ROWASA.

5.4 Hepatic Failure There have been reports of hepatic failure in patients with pre-existing liver disease who have been administered other products containing mesalamine. Evaluate the risks and benefits of using ROWASA in patients with known liver impairment.

5.5 Severe Cutaneous Adverse Reactions Severe cutaneous adverse reactions, including Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN), drug reaction with eosinophilia and systemic symptoms (DRESS), and acute generalized exanthematous pustulosis (AGEP) have been reported with the use of mesalamine [see Adverse Reactions (6) ] . Discontinue ROWASA at the first signs or symptoms of severe cutaneous adverse reactions or other signs of hypersensitivity and consider further evaluation.

5.6 Photosensitivity Patients with pre‑existing skin conditions such as atopic dermatitis and atopic eczema have reported more severe photosensitivity reactions. Advise patients to avoid sun exposure, wear protective clothing, and use a broad-spectrum sunscreen when outdoors.

5.7 Nephrolithiasis Cases of nephrolithiasis have been reported with the use of mesalamine, including stones with 100% mesalamine content. Mesalamine‑containing stones are radiotransparent and undetectable by standard radiography or computed tomography (CT). Ensure adequate fluid intake during treatment.

5.8 Interference with Laboratory Tests Use of mesalamine may lead to spuriously elevated test results when measuring urinary normetanephrine by liquid chromatography with electrochemical detection because of the similarity in the chromatograms of normetanephrine and the main metabolite of mesalamine, N‑acetyl‑5‑aminosalicylic acid (N‑Ac‑5‑ASA). Consider an alternative, selective assay for normetanephrine.

5.9 Intracranial Hypertension Intracranial hypertension has been reported postmarketing in patients receiving mesalamine and sulfasalazine. Signs and symptoms of intracranial hypertension can include severe or recurrent headache, blurred vision, diplopia, and potential vision loss; papilledema can be found on fundoscopy. These signs and symptoms are similar to idiopathic intracranial hypertension. If an unusual headache or visual disturbance occurs during treatment, immediately discontinue ROWASA and refer the patient for further evaluation .

The following clinically significant adverse reactions are described elsewhere in the labeling:

• Hypersensitivity reactions [see Warnings and Precautions (5.1) ]
• Renal impairment [see Warnings and Precautions (5.2) ]
• Mesalamine-induced acute intolerance syndrome [see Warnings and Precautions (5.3) ]
• Hepatic failure [see Warnings and Precautions (5.4) ]
• Severe cutaneous adverse reactions [see Warnings and Precautions (5.5) ]
• Photosensitivity [see Warnings and Precautions (5.6) ]
• Nephrolithiasis [see Warnings and Precautions (5.7) ]
• Intracranial Hypertension [see Warnings and Precautions (5.9) ] Most common adverse reactions (≥1%) are: gas/flatulence, flu, fever, leg/joint pain, hemorrhoids, rectal pain and hair loss. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Meda Pharmaceuticals Inc at 1-866-210-5949 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. Table 1: Adverse Reactions reported in 1% or more of ROWASA-treated patients and greater than placebo in Clinical Trials of ROWASA in Adult Patients with Ulcerative Colitis, Proctosigmoiditis or Proctitis Adverse Reaction ROWASA (N=815) % Placebo (N=128) % Gas/Flatulence 6 4 Flu 5 1 Fever 3 0 Leg/Joint pain 2 1 Hemorrhoids 1 1 Rectal pain 1 0 Hair loss 1 0

6.2 Postmarketing Experience The following adverse reactions have been identified during post‑approval use of 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. Cardiac Disorders: myocarditis, pericarditis [see Warnings and Precautions (5.1) ] Gastrointestinal Disorders: pancreatitis Hematologic Disorders: agranulocytosis, aplastic anemia, eosinophilia, leukopenia, neutropenia, pancytopenia, thrombocytopenia Hepatic Disorders: elevated liver enzymes, hepatic failure [see Warnings and Precautions (5.4) ] Immune System Disorders: vasculitis Nervous System: intracranial hypertension Renal and Urinary Disorders: acute renal failure, chronic renal failure, interstitial nephritis, nephrogenic diabetes insipidus, nephrolithiasis, nephrotoxicity [see Warnings and Precautions (5.2) , (5.7) ]

• Urine discoloration occurring ex-vivo caused by contact of mesalamine including inactive metabolite, with surfaces or water treated with hypochlorite-containing bleach Reproductive System and Breast Disorders: reversible oligospermia Respiratory, Thoracic, and Mediastinal Disorders: fibrosing alveolitis, pleurisy/pleuritis Skin and Subcutaneous Tissue Disorders: AGEP, DRESS, SJS/TEN [see Warnings and Precautions (5.5) ]

• Nephrotoxic Agents including Non-Steroidal Anti-inflammatory Drugs (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 dyscrasias; 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 nephrotoxicity. Monitor patients taking nephrotoxic drugs for changes in renal function and mesalamine-related adverse reactions [see Warnings and Precautions (5.2) ] .

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 ROWASA 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 ROWASA may lead to spuriously elevated test results when measuring urinary normetanephrine by liquid chromatography with electrochemical detection [see Warnings and Precautions (5.8) ] . Consider an alternative, selective assay for normetanephrine.

Geriatric Patients : Increased risk of blood dyscrasias; monitor complete blood cell counts and platelet counts. ( 8.5 )

8.1 Pregnancy Risk Summary Published data from meta-analyses, cohort studies and case series on the use of mesalamine during pregnancy have not reliably informed an association with mesalamine and major birth defects, miscarriage, or adverse maternal or fetal outcomes (see Data ) . There are adverse effects on maternal and fetal outcomes associated with ulcerative colitis in pregnancy (see Clinical Considerations ) . In animal reproduction studies, rats and rabbits administered mesalamine during organogenesis at oral doses up to 5 and 8 times the maximum recommended human dose, respectively, did not reveal any evidence of harm to the embryo or the fetus (see Data ) . The background risk of major birth defects and miscarriage for the indicated population is unknown. All pregnancies have a background risk of birth defect, loss, or other adverse outcomes. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2% to 4% and 15% to 20%, respectively. Clinical Considerations Disease-associated maternal and embryo/fetal risk Published data suggest that increased disease activity is associated with the risk of developing adverse pregnancy outcomes in women with ulcerative colitis. Adverse pregnancy outcomes include preterm delivery (before 37 weeks of gestation), low birth weight (less than 2500 g) infants, and small for gestational age at birth. Data Human Data Published data from meta-analyses, cohort studies and case series on the use of mesalamine, the active moiety of ROWASA, during early pregnancy (first trimester) and throughout pregnancy have not reliably informed an association of mesalamine and major birth defects, miscarriage, or adverse maternal or fetal outcomes. There is no clear evidence that mesalamine exposure in early pregnancy is associated with an increased risk in major congenital malformations, including cardiac malformations. Published epidemiologic studies have important methodological limitations which hinder interpretation of the data, including inability to control for confounders, such as underlying maternal disease, and maternal use of concomitant medications, and missing information on the dose and duration of use for mesalamine products. Animal Data Reproduction studies have been performed with mesalamine in rats and rabbits during organogenesis at oral doses up to 5 and 8 times respectively, the maximum recommended human dose, and have revealed no evidence of harm to the embryo or the fetus.

8.2 Lactation Risk Summary Data from published literature report the presence of mesalamine and its metabolite, N‑acetyl‑5‑aminosalicylic acid in human milk in small amounts with relative infant doses (RID) of 0.1% or less for mesalamine (see Data ) . There are case reports of diarrhea observed in breastfed infants exposed to mesalamine (see Clinical Considerations ) . There is no information on the effects of mesalamine on milk production. The lack of clinical data during lactation precludes a clear determination of the risk of ROWASA to an infant during lactation; therefore, the developmental and health benefits of breastfeeding should be considered along with the mother’s clinical need for ROWASA and any potential adverse effects on the breastfed child from ROWASA or from the underlying maternal condition. Clinical Considerations Advise the caregiver to monitor the breastfed infant for diarrhea. Data In published lactation studies, maternal mesalamine doses from various oral and rectal formulations and products ranged from 500 mg to 4.8 g daily. The average concentration of mesalamine in milk ranged from non‑detectable to 0.5 mg/L. The average concentration of N‑acetyl‑5-aminosalicylic acid in milk ranged from 0.2 to 9.3 mg/L. Based on these concentrations, estimated infant daily dosages for an exclusively breastfed infant are 0 to 0.075 mg/kg/day of mesalamine (RID 0% to 0.1%) and 0.03 to 1.4 mg/kg/day of N‑acetyl‑5‑aminosalicylic acid.

8.4 Pediatric Use Safety and effectiveness in pediatric patients have not been established.

8.5 Geriatric Use Clinical trials of ROWASA did not include sufficient numbers of patients aged 65 years and over to determine whether they respond differently from younger patients. Reports from uncontrolled clinical studies and postmarketing reporting systems suggested a higher incidence of blood dyscrasias (i.e., agranulocytosis, neutropenia and pancytopenia) in patients receiving mesalamine-containing products such as ROWASA who were 65 years or older compared to younger adult patients, which may also be associated with ulcerative colitis, use of interacting drugs, or reduced renal function. Consider monitoring complete blood cell counts and platelet counts in patients 65 years and over during treatment with ROWASA. In general, consider the greater frequency of decreased hepatic, renal, or cardiac function, and of concurrent disease or other drug therapy in patients 65 years and over when prescribing ROWASA.

8.6 Renal Impairment Mesalamine is known to be substantially excreted by the kidney, and the risk of toxic reactions may be greater in patients with impaired renal function. Evaluate renal function in all patients prior to initiation and periodically while on ROWASA therapy. Monitor patients with known renal impairment or history of renal disease or taking nephrotoxic drugs for decreased renal function and mesalamine-related adverse reactions. Discontinue ROWASA if renal function deteriorates while on therapy [see Warnings and Precautions (5.2) ] .

The mechanism of action of 5-ASA (mesalamine) is not fully understood, but appears to be a topical 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 mesalamine diminishes inflammation by blocking cyclooxygenase and inhibiting prostaglandin production in the colon.