Victoza (liraglutide) Side Effects, Warnings, and Drug Interactions

Victoza (liraglutide) is a glucagon-like peptide-1 (GLP-1) receptor agonist used with diet and exercise to improve control of blood sugar in adults with type 2 diabetes. Victoza should not be used for treating diabetic ketoacidosis or type 1 diabetes and should not be used as the first agent for treating diabetes after failure of diet and exercise.

Common side effects of Victoza include nausea, vomiting, diarrhea, constipation, upper respiratory tract infection, headache, flu-like symptoms, dizziness, sinusitis, back pain, injection site reactions, and low blood sugar (hypoglycemia) in combination with other diabetes drugs.

Serious side effects of Victoza include acute pancreatitis and thyroid tumors.

Drug interactions of Victoza include other drugs that are taken orally and insulin or drugs that stimulate release of insulin (for example, glyburide [Micronase, Diabeta, Glynase, Prestab]). There are no adequate studies of Victoza in pregnant women. Most experts agree that insulin is the drug of choice in pregnant women with diabetes. There are no adequate studies of Victoza in nursing mothers, and it is not known whether Victoza is excreted in human breast milk.

The most common side effects of Victoza are:

• Nausea
• Vomiting
• Diarrhea
• Constipation
• Upper respiratory tract infection
• Headache
• Flu-like symptoms
• Dizziness
• Sinusitis
• Back pain
• Reactions at the injection site
• Combining Victoza with insulin or drugs that stimulate release of insulin (for example, glyburide) may increase the occurrence of low blood sugar (hypoglycemia). The dose of insulin or the insulin release stimulating drug should be reduced.
• There have been reports of acute pancreatitis associated with the use of Victoza. Patients developing severe, persistent abdominal pain that might be caused by pancreatitis, should seek prompt medical attention. If pancreatitis is suspected, Victoza should be discontinued and not started again until the presence of pancreatitis has been excluded.
• Victoza can cause thyroid tumors that occur more frequently at higher doses and with longer duration of treatment. Since Victoza is a synthetic protein patients may develop antibodies to Victoza. Victoza antibodies may reduce the effectiveness of Victoza.

The following serious adverse reactions are described below or elsewhere in the prescribing information:

• Risk of Thyroid C-cell Tumors
• Pancreatitis
• Use with Medications Known to Cause Hypoglycemia
• Renal Impairment
• Hypersensitivity Reactions

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.

Common Adverse Reactions

The safety of Victoza in subjects with type 2 diabetes was evaluated in 5 glycemic control, placebocontrolled trials in adults and one trial of 52 weeks duration in pediatric patients 10 years of age and older.

The data in Table 1 reflect exposure of 1673 adult patients to Victoza and a mean duration of exposure to Victoza of 37.3 weeks. The mean age of adult patients was 58 years, 4% were 75 years or older and 54% were male. The population was 79% White, 6% Black or African American, 13% Asian; 4% were of Hispanic or Latino ethnicity.

At baseline the population had diabetes for an average of 9.1 years and a mean HbA1c of 8.4%. Baseline estimated renal function was normal or mildly impaired in 88.1% and moderately impaired in 11.9% of the pooled population.

Table 1 shows common adverse reactions in adults, excluding hypoglycemia, associated with the use of Victoza. These adverse reactions occurred more commonly on Victoza than on placebo and occurred in at least 5% of patients treated with Victoza. Overall, the type, and severity of adverse reactions in adolescents and children aged 10 years and above were comparable to that observed in the adult population.

Table 1 : Adverse reactions reported in ≥ 5% of Victoza-treated patients

Cumulative proportions were calculated combining studies using Cochran-Mantel-Haenszel weights.

In an analysis of placebo- and active-controlled trials, the types and frequency of common adverse reactions, excluding hypoglycemia, were similar to those listed in Table 1.

Other Adverse Reactions

Gastrointestinal Adverse Reactions

In the pool of 5 glycemic control, placebo-controlled clinical trials, withdrawals due to gastrointestinal adverse reactions, occurred in 4.3% of Victoza-treated patients and 0.5% of placebo-treated patients.

Withdrawal due to gastrointestinal adverse events mainly occurred during the first 2-3 months of the trials.

Injection Site Reactions

Injection site reactions (e.g., injection site rash, erythema) were reported in approximately 2% of Victoza-treated patients in the five double-blind, glycemic control trials of at least 26 weeks duration. Less than 0.2% of Victoza-treated patients discontinued due to injection site reactions.

Hypoglycemia

In 5 adult glycemic control, placebo-controlled clinical trials of at least 26 weeks duration, hypoglycemia requiring the assistance of another person for treatment occurred in 8 Victoza-treated patients (7.5 events per 1000 patient-years). Of these 8 Victoza-treated patients, 7 patients were concomitantly using a sulfonylurea.

Table 2 : Adult Incidence (%) and Rate (episodes/patient year) of Hypoglycemia in 26-Week Combination Therapy Placebo- controlled Trials

In a 26-week pediatric placebo-controlled clinical trial with a 26-week open-label extension, 21.2% of Victoza treated patients (mean age 14.6 years) with type 2 diabetes, had hypoglycemia with a blood glucose <54 mg/dL with or without symptoms (335 events per 1000 patient years). No severe hypoglycemic episodes occurred in the Victoza treatment group (severe hypoglycemia was defined as an episode requiring assistance of another person to actively administer carbohydrate, glucagon, or other resuscitative actions).

Papillary Thyroid Carcinoma

In glycemic control trials of Victoza, there were 7 reported cases of papillary thyroid carcinoma in patients treated with Victoza and 1 case in a comparator-treated patient (1.5 vs. 0.5 cases per 1000 patient-years). Most of these papillary thyroid carcinomas were <1 cm in greatest diameter and were diagnosed in surgical pathology specimens after thyroidectomy prompted by findings on protocolspecified screening with serum calcitonin or thyroid ultrasound.

Cholelithiasis And Cholecystitis

In glycemic control trials of Victoza, the incidence of cholelithiasis was 0.3% in both Victozatreated and placebo-treated patients. The incidence of cholecystitis was 0.2% in both Victoza-treated and placebo-treated patients.

In the LEADER trial, the incidence of cholelithiasis was 1.5% (3.9 cases per 1000 patient years of observation) in Victoza-treated and 1.1% (2.8 cases per 1000 patient years of observation) in placebo-treated patients, both on a background of standard of care. The incidence of acute cholecystitis was 1.1% (2.9 cases per 1000 patient years of observation) in Victoza-treated and 0.7% (1.9 cases per 1000 patient years of observation) in placebo-treated patients.

Laboratory Tests

Bilirubin

In the five glycemic control trials of at least 26 weeks duration, mildly elevated serum bilirubin concentrations (elevations to no more than twice the upper limit of the reference range) occurred in 4.0% of Victoza-treated patients, 2.1% of placebo-treated patients and 3.5% of active-comparator-treated patients. This finding was not accompanied by abnormalities in other liver tests. The significance of this isolated finding is unknown.

Calcitonin

Calcitonin, a biological marker of MTC, was measured throughout the clinical development program. At the end of the glycemic control trials, adjusted mean serum calcitonin concentrations were higher in Victoza-treated patients compared to placebo-treated patients but not compared to patients receiving active comparator.

Between group differences in adjusted mean serum calcitonin values were approximately 0.1 ng/L or less. Among patients with pretreatment calcitonin <20 ng/L, calcitonin elevations to >20 ng/L occurred in 0.7% of Victoza-treated patients, 0.3% of placebo-treated patients, and 0.5% of active-comparator-treated patients. The clinical significance of these findings is unknown.

Lipase And Amylase

In one glycemic control trial in renal impairment patients, a mean increase of 33% for lipase and 15% for amylase from baseline was observed for Victoza-treated patients while placebo-treated patients had a mean decrease in lipase of 3% and a mean increase in amylase of 1%.

In the LEADER trial, serum lipase and amylase were routinely measured. Among Victoza-treated patients, 7.9% had a lipase value at any time during treatment of greater than or equal to 3 times the upper limit of normal compared with 4.5% of placebo-treated patients, and 1% of Victoza-treated patients had an amylase value at any time during treatment of greater than or equal to 3 times the upper limit of normal versus 0.7% of placebo-treated patients.

The clinical significance of elevations in lipase or amylase with Victoza is unknown in the absence of other signs and symptoms of pancreatitis.

Vital Signs

Victoza did not have adverse effects on blood pressure. Mean increases from baseline in heart rate of 2 to 3 beats per minute have been observed with Victoza compared to placebo.

Immunogenicity

Consistent with the potentially immunogenic properties of protein and peptide pharmaceuticals, patients treated with Victoza may develop anti-liraglutide antibodies. The detection of antibody formation is highly dependent on the sensitivity and specificity of the assay.

• Additionally, the observed incidence of antibody (including neutralizing antibody) positivity in an assay may be influenced by several factors including assay methodology, sample handling, timing of sample collection, concomitant medications, and underlying disease. For these reasons, the incidence of antibodies to liraglutide cannot be directly compared with the incidence of antibodies of other products.
• Approximately 50-70% of Victoza-treated patients in five double-blind clinical trials of 26 weeks duration or longer were tested for the presence of anti-liraglutide antibodies at the end of treatment. Low titers (concentrations not requiring dilution of serum) of anti-liraglutide antibodies were detected in 8.6% of these Victoza-treated patients.
• Cross-reacting anti-liraglutide antibodies to native glucagon-like peptide-1 (GLP-1) occurred in 6.9% of the Victoza-treated patients in the double-blind 52-week monotherapy trial and in 4.8% of the Victoza-treated patients in the double-blind 26-week add-on combination therapy trials. These cross-reacting antibodies were not tested for neutralizing effect against native GLP-1, and thus the potential for clinically significant neutralization of native GLP-1 was not assessed. Antibodies that had a neutralizing effect on liraglutide in an in vitro assay occurred in 2.3% of the Victoza-treated patients in the double-blind 52-week monotherapy trial and in 1.0% of the Victoza-treated patients in the double-blind 26-week add-on combination therapy trials.
• Antibody formation was not associated with reduced efficacy of Victoza when comparing mean HbA1c of all antibody-positive and all antibody-negative patients. However, the 3 patients with the highest titers of anti-liraglutide antibodies had no reduction in HbA1c with Victoza treatment.

In five double-blind glycemic control trials of Victoza, events from a composite of adverse events potentially related to immunogenicity (e.g. urticaria, angioedema) occurred among 0.8% of Victoza-treated patients and among 0.4% of comparator-treated patients. Urticaria accounted for approximately one-half of the events in this composite for Victoza-treated patients. Patients who developed antiliraglutide antibodies were not more likely to develop events from the immunogenicity events composite than were patients who did not develop anti-liraglutide antibodies.

• In the LEADER trial, anti-liraglutide antibodies were detected in 11 out of the 1247 (0.9%) Victoza-treated patients with antibody measurements.
• Of the 11 Victoza-treated patients who developed anti-liraglutide antibodies, none were observed to develop neutralizing antibodies to liraglutide, and 5 patients (0.4%) developed cross-reacting antibodies against native GLP-1.
• In a clinical trial with pediatric patients 10 to 17 years, anti-liraglutide antibodies were detected in 1 (1.5%) Victoza treated patient at week 26 and 5 (8.5%) Victoza treated patients at week 53. None of the 5 had antibodies cross reactive to native GLP-1 or had neutralizing antibodies.

Post-Marketing Experience

The following additional adverse reactions have been reported during post-approval use of Victoza. Because these events are reported voluntarily from a population of uncertain size, it is generally not possible to reliably estimate their frequency or establish a causal relationship to drug exposure.

• Medullary thyroid carcinoma
• Dehydration resulting from nausea, vomiting and diarrhea.
• Increased serum creatinine, acute renal failure or worsening of chronic renal failure, sometimes requiring hemodialysis.
• Angioedema and anaphylactic reactions.
• Allergic reactions: rash and pruritus
• Acute pancreatitis, hemorrhagic and necrotizing pancreatitis sometimes resulting in death
• Hepatobiliary disorders: elevations of liver enzymes, hepatitis

Oral Medications

Victoza causes a delay of gastric emptying, and thereby has the potential to impact the absorption of concomitantly administered oral medications. In clinical pharmacology trials, Victoza did not affect the absorption of the tested orally administered medications to any clinically relevant degree. Nonetheless, caution should be exercised when oral medications are concomitantly administered with Victoza.

Concomitant Use With An Insulin Secretagogue (e.g., Sulfonylurea) Or With Insulin

When initiating Victoza, consider reducing the dose of concomitantly administered insulin secretagogues (such as sulfonylureas) or insulin to reduce the risk of hypoglycemia.