No case of overdose has been reported with GIAZO. GIAZO is an aminosalicylate, and symptoms of salicylate toxicity include: hematemesis, tachypnea, hyperpnea, tinnitus, deafness, lethargy, seizures, confusion, or dyspnea. Severe intoxication may lead to electrolyte and blood pH imbalance and potentially to other organ (e.g., renal and liver) involvement. There is no specific antidote for balsalazide overdose. Proper medical care should be sought immediately with appropriate supportive care, including the possible use of emesis, cathartics, and activated charcoal to prevent further absorption.
GIAZO is contraindicated in patients with hypersensitivity to salicylates, aminosalicylates or their metabolites, or to any of the components of GIAZO tablets.
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.
The data described below reflect exposure of GIAZO in 565 ulcerative colitis patients with mildly to moderately active disease. GIAZO was evaluated in one placebocontrolled trial (168 treated with GIAZO), one active-controlled trial (210 treated with GIAZO); and a subset of these patients also participated in an uncontrolled, open-label, extension study (additional 187 treated with GIAZO). The population studied had a mean age of 43.1 (range: 18-80) years; approximately 94% of patients were < 65 years old, 49% were male, and 84% were white.
In the placebo-controlled trial, the most common adverse reactions with GIAZO in male patients were headache, nasopharyngitis, anemia, diarrhea, fatigue, pharyngolaryngeal pain, and urinary tract infection. 10% of patients in the GIAZO group and 13% of patients in the placebo group discontinued treatment due to an adverse reaction. The majority of adverse reactions were mild to moderate in severity. The most common serious adverse reactions in both the placebo and GIAZO groups were gastrointestinal disorders, which were mainly associated with symptoms of ulcerative colitis.
Adverse reactions occurring in at least 2% of male patients and at a rate numerically higher than placebo in the placebo-controlled trial are listed in Table 1.
Table 1: Adverse Reactions Experienced by at Least 2%
of GIAZO– Treated Male Patients and at a Rate Numerically Greater than Placebo
in a Placebo-Controlled Trial
| Adverse Reaction | GIAZO 6.6 g/day N=82 |
PLACEBO N=37 |
| Anemia | 3.7% | 0% |
| Diarrhea | 3.7% | 0% |
| Pharyngolaryngeal Pain | 3.7% | 0% |
| Urinary Tract Infection | 3.7% | 0% |
| Arthralgia | 2.4% | 0% |
| Insomnia | 2.4% | 0% |
| Musculoskeletal Pain | 2.4% | 0% |
Data collected from all three trials (placebo-controlled, active-controlled, and openlabel) showed that female patients reported adverse reactions more frequently than did male patients (76% and 66%, respectively).
The following adverse reactions, presented by body system, were reported by less than 1% of GIAZO-treated ulcerative colitis patients in controlled trials.
Cardiovascular and Vascular: increased blood pressure, increased heart rate
Dermatological: erythema nodosum, rash
Respiratory, Thoracic and Mediastinal Disorders: dyspnea
Gastrointestinal Disorders: abdominal pain, constipation, defecation urgency, diarrhea, dry mouth, hard feces, flatulence, gastroesophageal reflux disease, vomiting
Hepatobiliary Disorders: increased aspartate aminotransferase
Infections and Infestations: gastroenteritis, upper respiratory infection
Musculoskeletal and Connective Tissue Disorders: arthralgia, back pain, myalgia
Nervous System Disorders: dizziness, lethargy
General Disorders and Administrative Site Disorders: face edema, fatigue, malaise, pain, pyrexia, swelling
Postmarketing ExperienceBecause these reactions are reported voluntarily from a population of unknown size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure. These adverse reactions have been chosen for inclusion due to a combination of seriousness, frequency of reporting, or potential causal connection to products which contain or are metabolized to mesalamine, including balsalazide.
Cardiovascular and Vascular: myocarditis, pericarditis, vasculitis
Respiratory: alveolitis, pleural effusion, pneumonia (with and without eosinophilia)
Gastrointestinal: pancreatitis
Renal: interstitial nephritis, renal failure.
Hepatobiliary Disorders: elevated liver enzymes (AST, ALT, GGT, LDH, alkaline phosphatase), elevated bilirubin, jaundice, cholestatic jaundice, cirrhosis, hepatocellular damage including liver necrosis and liver failure, Kawasaki-like syndrome including hepatic dysfunction. Some of these cases were fatal.
Dermatological: alopecia, pruritus
GIAZO is indicated for the treatment of mildly to moderately active ulcerative colitis in male patients 18 years of age and older.
Limitations Of UseFollowing oral administration, balsalazide is cleaved by azoreductases produced by anaerobic bacteria found in the gut, to release equimolar quantities of 5-ASA, the active moiety, and 4-aminobenzoyl-ß-alanine (4-ABA), a carrier moiety. Both of these moieties are N-acetylated to form N-Ac-5-ASA and N-Ac-4-ABA, respectively.
AbsorptionAfter single-dose administration of 3.3 g GIAZO in 18 healthy subjects, the median time of peak plasma concentration (Tmax) was 0.5 hr for balsalazide, while the median Tmax was 12 hr for both 5-ASA and N-Ac-5-ASA (Table 2). Pharmacokinetic parameters exhibited high variability, with %CV ranging from 31% to 67% for AUC and from 27% to 68% for Cmax.
Pharmacokinetics were also estimated in healthy volunteers after repeated doses of 3.3 g GIAZO tablets every 12 hours for 7 days. After multiple doses, steady-state was achieved after about 3 days for balsalazide and all metabolites. The AUC and Cmax were the highest for N-Ac-5-ASA, followed by 5-ASA and balsalazide. There was minimal accumulation of balsalazide, as suggested by a 1.2-fold increase in AUC; however, a relatively larger increase in the systemic exposure to metabolites was observed at steady-state. The accumulation ratios based on AUC for the metabolites were 6.1 for 5-ASA, 3.6 for N-Ac-5-ASA, 4.8 for 4-ABA, and 3.6 for N-Ac-4-ABA.
Table 2: Pharmacokinetic Parameters for Balsalazide
and Metabolites (5- ASA and N-Ac-5-ASA) Following Single- and Repeated-Doses
(Q12) of 3.3 g Balsalazide Disodium as GIAZO (N=18)
| Parameter | Single Dose | Repeated Dose | ||
| Mean | SD | Mean | SD | |
| Cmax (mcg/mL) | ||||
| Balsalazide | 0.3 | .2 0. | 0.3 | 0.2 |
| 5-ASA | 0.5 | 0.3 | 1.5 | 0.6 |
| N-Ac-5-ASA | 1.2 | 0.4 | 2.2 | 0.6 |
| Tmaxa (hours) | ||||
| Balsalazide | 0.5 | (0.5-2) | 0.5 | (0.5-2) |
| 5-ASA | 12 | (8-16) | 12 | (1.5-16) |
| N-Ac-5-ASA | 12 | (8-16) | 10 | (1-16) |
| AUCtau (mcg•h/mL) | ||||
| Balsalazide | 1.3 | 0.7 | 1.6 | 0.9 |
| 5-ASA | .2 2. | 1.6 | 13.4 | 6.3 |
| N-Ac-5-ASA | 5.9 | .9 2. | 21 | 6.4 |
| AUC0-∞ (mcg•h/mL) | ||||
| Balsalazide | 1.4 | 0.8 | NA | NA |
| 5-ASA | 8.5 | 3.9 | NA | NA |
| N-Ac-5-ASA | 33.5 | 14.1 | NA | NA |
| T½b (hour) | ||||
| Balsalazide | 1.9 | 0.7 | 8.4 | 12.4 |
| 5-ASA | 9.5b | 10.1 | 9.0 | 8.6 |
| N-Ac-5-ASA | 10.4b | 17.6 | 7.2 | 6.8 |
| a Expressed as median and range. b N=17 |
||||
After administration of single dose of 3.3 g (3 × 1.1 g tablets) of GIAZO with a high-fat meal in healthy volunteers, the AUC of balsalazide was unaffected compared to fasted administration, but the presence of food reduced both peak concentrations and AUC of the metabolites 5-ASA and N-Ac-5-ASA. A high fat meal increased the median Tmax for balsalazide from 0.5 to 2 hours; for 5-ASA from 12 to 24 hours; and for N-Ac-5-ASA from 12 to 24 hours. Under fed conditions, the mean Cmax was reduced by 44% for balsalazide, 65% for 5-ASA, and 48% for N-Ac-5-ASA. No significant changes were observed for AUC0-∞ for balsalazide; however, AUC0-∞ was reduced for 5-ASA by 46% and for N-Ac-5-ASA by 17%.
DistributionThe binding of balsalazide to human plasma proteins was ≥ 99%; 5-ASA and N-Ac-5- ASA were 43% and 78% bound, respectively, to plasma proteins.
Metabolism And ExcretionFollowing oral administration, balsalazide is cleaved by bacterial azoreduction to release equimolar quantities of 5-ASA, the active moiety, and 4-ABA, a carrier moiety. Mesalamine (5-ASA) and 4-ABA are further acetylated to N-Ac-5-ASA and N-Ac-4- ABA, respectively in the intestinal mucosa and liver. The terminal half-life was 1.9 h for balsalazide, 9.5 h for 5-ASA, and 10.5 h for N-Ac-5-ASA.
At steady-state following administration of repeated doses of 3.3 g GIAZO every 12 hours in healthy volunteers, the combined % of dose excreted in urine for balsalazide and its metabolites over 12 hours was 23%. The mean % of dose excreted in urine over 12 hours was 0.16% for balsalazide, 4.6% for 5-ASA, 15.6% for N-Ac-5- ASA, 0.40% for 4-ABA, and 1.8% for N-Ac-4-ABA.
Pregnancy Category B. Reproduction studies were performed in rats and rabbits at oral doses up to 2 g/kg/day, 2.5 and 4.9 times the recommended human dose based on body surface area for the rat and rabbit, respectively, and revealed no evidence of impaired fertility or harm to the fetus due to balsalazide disodium. There are, however, no adequate and well-controlled studies in pregnant women. Because animal reproduction studies are not always predictive of human response, this drug should be used during pregnancy only if clearly needed.
Mesalamine, a metabolite of GIAZO, is known to cross the placental barrier.
GIAZO is available as yellow, oval, film-coated tablets containing 1.1 g balsalazide disodium, with BZT debossed on one side of the tablet.
Storage And HandlingGIAZO is available as oval, yellow, film-coated tablets containing 1.1 g balsalazide disodium, with BZT debossed on one side of the tablet.
Bottles of 180 Tablets NDC 65649-102-02
StorageStore at 20° to 25°C (68° to 77°F); excursions permitted between 15° and 30°C (59° and 86°F).
Manufactured for: Salix Pharmaceuticals, a division of Valeant Pharmaceuticals North America LC Bridgewater, NJ 08807 USA. Revised: June 2016
Included as part of the PRECAUTIONS section.
PRECAUTIONS Exacerbations Of Ulcerative ColitisBalsalazide is converted to mesalamine, which has been associated with an acute intolerance syndrome that may be difficult to distinguish from an exacerbation of ulcerative colitis. In controlled clinical trials with GIAZO in adults with ulcerative colitis, 7% of male patients reported exacerbation of the symptoms of ulcerative colitis. Symptoms include cramping, acute abdominal pain and bloody diarrhea, sometimes fever, headache, and rash. Observe patients closely for worsening of these symptoms while on treatment. If acute intolerance syndrome is suspected, promptly discontinue treatment with GIAZO.
Renal ImpairmentRenal impairment, including minimal change nephropathy, acute and chronic interstitial nephritis and renal failure, has been reported in patients given products that release mesalamine in the gastrointestinal tract. Evaluate renal function prior to initiation of GIAZO therapy and periodically while on therapy. Exercise caution when using GIAZO in patients with known renal dysfunction or a history of renal disease.
Use In Hepatic ImpairmentThere have been reports of hepatic failure in patients with pre-existing liver disease who have been administered mesalamine. Because balsalazide is converted to mesalamine, use caution and consider liver function testing when administering GIAZO to patients with liver disease.
Nonclinical Toxicology Carcinogenesis, Mutagenesis, Impairment Of FertilityIn a 24-month rat (Sprague Dawley) carcinogenicity study, oral (dietary) balsalazide disodium at doses up to 2 g/kg/day was not tumorigenic. For a 50 kg person of average height this dose represents 2.5 times the recommended human dose on a body surface area basis. Balsalazide disodium was not genotoxic in the following in vitro or in vivo tests: Ames test, human lymphocyte chromosomal aberration test, and mouse lymphoma cell (L5178Y/TK+/-) forward mutation test, or mouse micronucleus
The compound 4-aminobenzoyl-ß-alanine, a metabolite of balsalazide disodium, was not genotoxic in the Ames test and the mouse lymphoma cell (L5178Y/TK+/-) forward mutation test but was positive in the human lymphocyte chromosomal aberration test. N-acetyl-4-aminobenzoyl-ß-alanine, a conjugated metabolite of balsalazide disodium, was not genotoxic in Ames test, the mouse lymphoma cell (L5178Y/TK+/-) forward mutation test, or the human lymphocyte chromosomal aberration test. Balsalazide disodium at oral doses up to 2 g/kg/day, 2.5 times the recommended human dose based on body surface area, was found to have no effect on fertility and reproductive performance in rats.
Use In Specific Populations PregnancyPregnancy Category B. Reproduction studies were performed in rats and rabbits at oral doses up to 2 g/kg/day, 2.5 and 4.9 times the recommended human dose based on body surface area for the rat and rabbit, respectively, and revealed no evidence of impaired fertility or harm to the fetus due to balsalazide disodium. There are, however, no adequate and well-controlled studies in pregnant women. Because animal reproduction studies are not always predictive of human response, this drug should be used during pregnancy only if clearly needed.
Mesalamine, a metabolite of GIAZO, is known to cross the placental barrier.
Nursing MothersIt is not known whether balsalazide disodium or its metabolites are excreted in human milk. Because many drugs are excreted in human milk, caution should be exercised when GIAZO is administered to a nursing woman.
Pediatric UseSafety and effectiveness of GIAZO in pediatric patients have not been established.
Geriatric UseReports from uncontrolled clinical studies and postmarketing reporting systems suggested a higher incidence of blood dyscrasias, i.e., neutropenia and pancytopenia, in patients who were 65 years or older who were taking mesalamine-containing products. GIAZO is converted into mesalamine in the colon. Caution should be taken to closely monitor blood cell counts during therapy.
Clinical trials of GIAZO did not include sufficient numbers of subjects aged 65 and over to determine whether they respond differently than younger subjects. Other reported clinical experience has not identified differences in responses between elderly and younger patients. In general, the greater frequency of decreased hepatic, renal, or cardiac function, and of concomitant disease or other drug therapy in elderly patients should be considered when prescribing GIAZO.
The dose is three 1.1 g GIAZO tablets to be taken 2 times a day with or without food (6.6 g per day) for up to 8 weeks.
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.
The data described below reflect exposure of GIAZO in 565 ulcerative colitis patients with mildly to moderately active disease. GIAZO was evaluated in one placebocontrolled trial (168 treated with GIAZO), one active-controlled trial (210 treated with GIAZO); and a subset of these patients also participated in an uncontrolled, open-label, extension study (additional 187 treated with GIAZO). The population studied had a mean age of 43.1 (range: 18-80) years; approximately 94% of patients were < 65 years old, 49% were male, and 84% were white.
In the placebo-controlled trial, the most common adverse reactions with GIAZO in male patients were headache, nasopharyngitis, anemia, diarrhea, fatigue, pharyngolaryngeal pain, and urinary tract infection. 10% of patients in the GIAZO group and 13% of patients in the placebo group discontinued treatment due to an adverse reaction. The majority of adverse reactions were mild to moderate in severity. The most common serious adverse reactions in both the placebo and GIAZO groups were gastrointestinal disorders, which were mainly associated with symptoms of ulcerative colitis.
Adverse reactions occurring in at least 2% of male patients and at a rate numerically higher than placebo in the placebo-controlled trial are listed in Table 1.
Table 1: Adverse Reactions Experienced by at Least 2%
of GIAZO– Treated Male Patients and at a Rate Numerically Greater than Placebo
in a Placebo-Controlled Trial
| Adverse Reaction | GIAZO 6.6 g/day N=82 |
PLACEBO N=37 |
| Anemia | 3.7% | 0% |
| Diarrhea | 3.7% | 0% |
| Pharyngolaryngeal Pain | 3.7% | 0% |
| Urinary Tract Infection | 3.7% | 0% |
| Arthralgia | 2.4% | 0% |
| Insomnia | 2.4% | 0% |
| Musculoskeletal Pain | 2.4% | 0% |
Data collected from all three trials (placebo-controlled, active-controlled, and openlabel) showed that female patients reported adverse reactions more frequently than did male patients (76% and 66%, respectively).
The following adverse reactions, presented by body system, were reported by less than 1% of GIAZO-treated ulcerative colitis patients in controlled trials.
Cardiovascular and Vascular: increased blood pressure, increased heart rate
Dermatological: erythema nodosum, rash
Respiratory, Thoracic and Mediastinal Disorders: dyspnea
Gastrointestinal Disorders: abdominal pain, constipation, defecation urgency, diarrhea, dry mouth, hard feces, flatulence, gastroesophageal reflux disease, vomiting
Hepatobiliary Disorders: increased aspartate aminotransferase
Infections and Infestations: gastroenteritis, upper respiratory infection
Musculoskeletal and Connective Tissue Disorders: arthralgia, back pain, myalgia
Nervous System Disorders: dizziness, lethargy
General Disorders and Administrative Site Disorders: face edema, fatigue, malaise, pain, pyrexia, swelling
Postmarketing ExperienceBecause these reactions are reported voluntarily from a population of unknown size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure. These adverse reactions have been chosen for inclusion due to a combination of seriousness, frequency of reporting, or potential causal connection to products which contain or are metabolized to mesalamine, including balsalazide.
Cardiovascular and Vascular: myocarditis, pericarditis, vasculitis
Respiratory: alveolitis, pleural effusion, pneumonia (with and without eosinophilia)
Gastrointestinal: pancreatitis
Renal: interstitial nephritis, renal failure.
Hepatobiliary Disorders: elevated liver enzymes (AST, ALT, GGT, LDH, alkaline phosphatase), elevated bilirubin, jaundice, cholestatic jaundice, cirrhosis, hepatocellular damage including liver necrosis and liver failure, Kawasaki-like syndrome including hepatic dysfunction. Some of these cases were fatal.
Dermatological: alopecia, pruritus
DRUG INTERACTIONSBased on in vitro studies, balsalazide and its metabolites [5-aminosalicylic acid (5- ASA), N-acetyl-5-aminosalicylic acid (N-Ac-5-ASA), 4-aminobenzoyl-ß-alanine (4-ABA), and N-acetyl-4-aminobenzoyl-ß-alanine (N-Ac-4-ABA)] are not expected to inhibit the metabolism of other drugs that are substrates of CYP1A2, CYP2C9, CYP2C19, CYP2D6, or CYP3A4/5.
