CANAGLIFLOZIN Drug Interactions: What You Need to Know

INTERACTIONS Table 8: Clinically Significant Drug Interactions with INVOKAMET or INVOKAMET XR Carbonic Anhydrase Inhibitors Clinical Impact: Carbonic anhydrase inhibitors frequently cause a decrease in serum bicarbonate and induce non-anion gap, hyperchloremic metabolic acidosis. Concomitant use of these drugs with INVOKAMET or INVOKAMET XR may increase the risk for lactic acidosis. Intervention: Consider more frequent monitoring of these patients. Examples: Topiramate or other carbonic anhydrase inhibitors (e.g., zonisamide, acetazolamide or dichlorphenamide)

Drugs That Reduce Metformin Clearance

Clinical Impact: Concomitant use of drugs that interfere with common renal tubular transport systems involved in the renal elimination of metformin (e.g., organic cationic transporter-2 [OCT2] / multidrug and toxin extrusion [MATE] inhibitors could increase systemic exposure to metformin and may increase the risk for lactic acidosis [see Clinical Pharmacology (12.3) ]. Intervention: Consider the benefits and risks of concomitant use. Examples: Ranolazine, vandetanib, dolutegravir, and cimetidine Alcohol Clinical Impact: Alcohol is known to potentiate the effect of metformin HCl on lactate metabolism. Intervention: Warn patients against excessive alcohol intake while receiving INVOKAMET or INVOKAMET XR.

Ugt

Enzyme Inducers Clinical Impact: UGT enzyme inducers decrease canagliflozin exposure which may reduce the effectiveness of INVOKAMET or INVOKAMET XR. Intervention: For patients with eGFR 60 mL/min/1.73 m 2 or greater, if an inducer of UGTs is co-administered with INVOKAMET or INVOKAMET XR, increase the total daily dose of canagliflozin to 200 mg in patients currently tolerating INVOKAMET or INVOKAMET XR with a total daily dose of canagliflozin 100 mg. The total daily dose of canagliflozin may be increased to 300 mg in patients currently tolerating canagliflozin 200 mg and who require additional glycemic control. For patients with eGFR less than 60 mL/min/1.73 m 2 , if an inducer of UGTs is co-administered with INVOKAMET or INVOKAMET XR, increase the total daily dose of canagliflozin to 200 mg in patients currently tolerating canagliflozin 100 mg [see Dosage and Administration (2.5) and Clinical Pharmacology (12.3) ] . Examples: Rifampin, phenytoin, phenobarbital, ritonavir Insulin or Insulin Secretagogues Clinical Impact: The risk of hypoglycemia is increased when INVOKAMET or INVOKAMET XR is used concomitantly with insulin secretagogues (e.g., sulfonylurea) or insulin. Intervention: Concomitant use may require a lower dosage of the insulin secretagogue or insulin to reduce the risk of hypoglycemia.

Drugs Affecting Glycemic Control Clinical

Impact: Certain drugs tend to produce hyperglycemia and may lead to loss of glycemic control. Intervention: When such drugs are administered to a patient receiving INVOKAMET or INVOKAMET XR, monitor for loss of blood glucose control. When such drugs are withdrawn from a patient receiving INVOKAMET or INVOKAMET XR, monitor for hypoglycemia. Examples: Thiazides and other diuretics, corticosteroids, phenothiazines, thyroid products, estrogens, oral contraceptives, phenytoin, nicotinic acid, sympathomimetics, calcium channel blockers, and isoniazid.

Digoxin Clinical

Impact: Canagliflozin increases digoxin exposure [see Clinical Pharmacology (12.3) ] . Intervention: Monitor patients taking INVOKAMET or INVOKAMET XR with concomitant digoxin for a need to adjust the dosage of digoxin.

Lithium Clinical

Impact: Concomitant use of an SGLT2 inhibitor with lithium may decrease serum lithium concentrations. Intervention: Monitor serum lithium concentration more frequently during INVOKAMET or INVOKAMET XR initiation and dosage changes.

Drug/Laboratory

Test Interference Positive Urine Glucose Test Clinical Impact: SGLT2 inhibitors increase urinary glucose excretion which will lead to positive urine glucose tests. Intervention: Monitoring glycemic control with urine glucose tests is not recommended in patients taking SGLT2 inhibitors. Use alternative methods to monitor glycemic control. Interference with 1,5-anhydroglucitol (1,5-AG)

Assay Clinical

Impact: Measurements of 1,5-AG are unreliable in assessing glycemic control in patients taking SGLT2 inhibitors. Intervention: Monitoring glycemic control with 1,5-AG assay is not recommended in patients taking SGLT2 inhibitors. Use alternative methods to monitor glycemic control.

Carbonic Anhydrase

Inhibitors: May increase risk of lactic acidosis. Consider more frequent monitoring ( 7 ) Drugs that Reduce Metformin Clearance: May increase risk of lactic acidosis. Consider benefits and risks of concomitant use ( 7 ) See full prescribing information for additional drug interactions and information on interference of INVOKAMET and INVOKAMET XR with laboratory tests. ( 7 )

INVOKAMET or INVOKAMET XR is contraindicated in patients with: Severe renal impairment (eGFR less than 30 mL/min/1.73 m 2 ) [see Warnings and Precautions (5.1) and Use in Specific Populations (8.6) ] . Acute or chronic metabolic acidosis, including diabetic ketoacidosis [see Warnings and Precautions (5.2) ] . Serious hypersensitivity reaction to canagliflozin or metformin HCl, such as anaphylaxis or angioedema [see Warnings and Precautions (5.9) and Adverse Reactions (6) ] . Severe renal impairment (eGFR less than 30 mL/min/1.73 m 2 ) ( 4 ) Metabolic acidosis, including diabetic ketoacidosis ( 4 ) Serious hypersensitivity reaction to canagliflozin or metformin HCl ( 4 )

AND PRECAUTIONS Diabetic Ketoacidosis in Patients with Type 1 Diabetes Mellitus and Other Ketoacidosis : Consider ketone monitoring in patients at risk for ketoacidosis, as indicated. Assess for ketoacidosis regardless of presenting blood glucose levels and discontinue INVOKAMET or INVOKAMET XR if ketoacidosis is suspected. Monitor patients for resolution of ketoacidosis before restarting ( 5.2 ).

Lower Limb

Amputation : Monitor patients for infection or ulcers of lower limb and discontinue if these occur ( 5.3 ).

Volume

Depletion : May result in acute kidney injury. Before initiating, assess and correct volume status in patients with renal impairment, elderly patients, or patients on loop diuretics. Monitor for signs and symptoms during therapy ( 5.4 ). Urosepsis and Pyelonephritis : Evaluate patients for signs and symptoms of urinary tract infections and treat promptly, if indicated ( 5.5 ). Hypoglycemia with Concomitant Use with Insulin or Insulin Secretagogues : Consider a lower dose of insulin or insulin secretagogue to reduce the risk of hypoglycemia when used in combination ( 5.6 ).

Necrotizing

Fasciitis of the Perineum (Fournier's Gangrene) : Serious, life-threatening cases have occurred in both females and males. Assess patients presenting with pain or tenderness, erythema, or swelling in the genital or perineal area, along with fever or malaise. If suspected, institute prompt treatment ( 5.7 ).

Genital Mycotic

Infections : Monitor and treat if indicated ( 5.8 ).

Hypersensitivity

Reactions : Discontinue and monitor until signs and symptoms resolve ( 5.9 ).

Bone

Fracture : Consider factors that contribute to fracture risk before initiating INVOKAMET or INVOKAMET XR ( 5.10 ). Vitamin B 12 Deficiency : Metformin HCl may lower vitamin B 12 levels. Measure hematological parameters annually and vitamin B 12 at 2- to 3-year intervals and manage any abnormalities ( 5.11 ).

5.1 Lactic Acidosis There have been post-marketing cases of metformin-associated lactic acidosis, including fatal cases. These cases had a subtle onset and were accompanied by nonspecific symptoms such as malaise, myalgias, abdominal pain, respiratory distress, or increased somnolence; however, hypothermia, hypotension and resistant bradyarrhythmias have occurred with severe acidosis. Metformin-associated lactic acidosis was characterized by elevated blood lactate concentrations (&gt;5 mmol/Liter), anion gap acidosis (without evidence of ketonuria or ketonemia), and an increased lactate:pyruvate ratio; metformin plasma levels generally &gt;5 mcg/mL. Metformin decreases liver uptake of lactate increasing lactate blood levels which may increase the risk of lactic acidosis, especially in patients at risk. If metformin-associated lactic acidosis is suspected, general supportive measures should be instituted promptly in a hospital setting, along with immediate discontinuation of INVOKAMET or INVOKAMET XR. In INVOKAMET or INVOKAMET XR-treated patients with a diagnosis or strong suspicion of lactic acidosis, prompt hemodialysis is recommended to correct the acidosis and remove accumulated metformin (metformin is dialyzable, with a clearance of up to 170 mL/min under good hemodynamic conditions). Hemodialysis has often resulted in reversal of symptoms and recovery. Educate patients and their families about the symptoms of lactic acidosis and if these symptoms occur instruct them to discontinue INVOKAMET or INVOKAMET XR and report these symptoms to their healthcare provider. For each of the known and possible risk factors for metformin-associated lactic acidosis, recommendations to reduce the risk of and manage metformin-associated lactic acidosis are provided below: Renal Impairment: The postmarketing metformin-associated lactic acidosis cases primarily occurred in patients with significant renal impairment. The risk of metformin accumulation and metformin-associated lactic acidosis increases with the severity of renal impairment because metformin is substantially excreted by the kidney. Clinical recommendations based upon the patient&apos;s renal function include <span class="opacity-50 text-xs">[see Dosage and Administration (2.4) and Clinical Pharmacology (12.3) ]</span>. Before initiating INVOKAMET or INVOKAMET XR, obtain an estimated glomerular filtration rate (eGFR). INVOKAMET or INVOKAMET XR is contraindicated in patients with an eGFR less than 30 mL/min/1.73 m 2 <span class="opacity-50 text-xs">[see Contraindications (4) ]</span> . Obtain an eGFR at least annually in all patients taking INVOKAMET or INVOKAMET XR. In patients at increased risk for the development of renal impairment (e.g., the elderly), renal function should be assessed more frequently.

Drug

Interactions: The concomitant use of INVOKAMET or INVOKAMET XR with specific drugs may increase the risk of metformin-associated lactic acidosis: those that impair renal function, result in significant hemodynamic change, interfere with acid-base balance or increase metformin accumulation (e.g. cationic drugs) [see Drug Interactions (7) ]. Therefore, consider more frequent monitoring of patients.

Age

65 or Greater: The risk of metformin-associated lactic acidosis increases with the patient's age because elderly patients have a greater likelihood of having hepatic, renal, or cardiac impairment than younger patients. Assess renal function more frequently in elderly patients [see Use in Specific Populations (8.5) ].

Radiological

Studies with Contrast: Administration of intravascular iodinated contrast agents in metformin-treated patients has led to an acute decrease in renal function and the occurrence of lactic acidosis. Stop INVOKAMET or INVOKAMET XR at the time of, or prior to, an iodinated contrast imaging procedure in patients with an eGFR less than 60 mL/min/1.73 m 2 ; in patients with a history of hepatic impairment, alcoholism, or heart failure; or in patients who will be administered intra-arterial iodinated contrast. Re-evaluate eGFR 48 hours after the imaging procedure, and restart INVOKAMET or INVOKAMET XR if renal function is stable. Surgery and Other Procedures: Withholding of food and fluids during surgical or other procedures may increase the risk for volume depletion, hypotension and renal impairment. INVOKAMET or INVOKAMET XR should be temporarily discontinued while patients have restricted food and fluid intake.

Hypoxic

States: Several of the postmarketing cases of metformin-associated lactic acidosis occurred in the setting of acute congestive heart failure (particularly when accompanied by hypoperfusion and hypoxemia). Cardiovascular collapse (shock), acute myocardial infarction, sepsis, and other conditions associated with hypoxemia have been associated with lactic acidosis and may also cause pre-renal azotemia. When such events occur, discontinue INVOKAMET or INVOKAMET XR.

Excessive Alcohol

Intake: Alcohol potentiates the effect of metformin on lactate metabolism and this may increase the risk of metformin-associated lactic acidosis. Warn patients against excessive alcohol intake while receiving INVOKAMET or INVOKAMET XR.

Hepatic

Impairment: Patients with hepatic impairment have developed metformin-associated lactic acidosis. This may be due to impaired lactate clearance resulting in higher lactate blood levels. Therefore, avoid use of INVOKAMET or INVOKAMET XR in patients with clinical or laboratory evidence of hepatic disease.

5.2 Diabetic Ketoacidosis in Patients with Type 1 Diabetes Mellitus and Other Ketoacidosis In patients with type 1 diabetes mellitus, INVOKAMET or INVOKAMET XR significantly increases the risk of diabetic ketoacidosis, a life-threatening event, beyond the background rate. In placebo-controlled trials of patients with type 1 diabetes mellitus, the risk of ketoacidosis was markedly increased in patients who received sodium glucose transporter 2 (SGLT2) inhibitors compared to patients who received placebo; this risk may be greater with higher doses of INVOKAMET or INVOKAMET XR. INVOKAMET or INVOKAMET XR is not indicated for glycemic control in patients with type 1 diabetes mellitus.

Type

2 diabetes mellitus and pancreatic disorders (e.g., history of pancreatitis or pancreatic surgery) are also risk factors for ketoacidosis. There have been postmarketing reports of fatal events of ketoacidosis in patients with type 2 diabetes mellitus using SGLT2 inhibitors, including INVOKAMET or INVOKAMET XR. Precipitating conditions for diabetic ketoacidosis or other ketoacidosis include under-insulinization due to insulin dose reduction or missed insulin doses, acute febrile illness, reduced caloric intake, ketogenic diet, surgery, volume depletion, and alcohol abuse. Signs and symptoms are consistent with dehydration and severe metabolic acidosis and include nausea, vomiting, abdominal pain, generalized malaise, and shortness of breath. Blood glucose levels at presentation may be below those typically expected for diabetic ketoacidosis (e.g., less than 250 mg/dL). Ketoacidosis and glucosuria may persist longer than typically expected. Urinary glucose excretion persists for 3 days after discontinuing INVOKAMET or INVOKAMET XR [see Clinical Pharmacology (12.2) ] ; however, there have been postmarketing reports of ketoacidosis and/or glucosuria lasting greater than 6 days and some up to 2 weeks after discontinuation of SGLT2 inhibitors. Consider ketone monitoring in patients at risk for ketoacidosis if indicated by the clinical situation. Assess for ketoacidosis regardless of presenting blood glucose levels in patients who present with signs and symptoms consistent with severe metabolic acidosis. If ketoacidosis is suspected, discontinue INVOKAMET or INVOKAMET XR, promptly evaluate, and treat ketoacidosis, if confirmed. Monitor patients for resolution of ketoacidosis before restarting INVOKAMET or INVOKAMET XR. Withhold INVOKAMET or INVOKAMET XR, if possible, in temporary clinical situations that could predispose patients to ketoacidosis. Resume INVOKAMET or INVOKAMET XR when the patient is clinically stable and has resumed oral intake [see Dosage and Administration (2.7)] . Educate all patients on the signs and symptoms of ketoacidosis and instruct patients to discontinue INVOKAMET or INVOKAMET XR and seek medical attention immediately if signs and symptoms occur.

5.3 Lower Limb Amputation An increased risk of lower limb amputations associated with canagliflozin, a component of INVOKAMET or INVOKAMET XR, versus placebo was observed in CANVAS (5.9 vs 2.8 events per 1,000 patient-years) and CANVAS-R (7.5 vs 4.2 events per 1,000 patient-years), two randomized, placebo-controlled trials evaluating adult patients with type 2 diabetes who had either established cardiovascular disease or were at risk for cardiovascular disease. The risk of lower limb amputations was observed at both the 100 mg and 300 mg once daily dosage regimens. The amputation data for CANVAS and CANVAS-R are shown in Tables 4 and 5, respectively <span class="opacity-50 text-xs">[see Adverse Reactions (6.1) ]</span> . Amputations of the toe and midfoot (99 out of 140 patients with amputations receiving canagliflozin in the two trials) were the most frequent; however, amputations involving the leg, below and above the knee, were also observed (41 out of 140 patients with amputations receiving canagliflozin in the two trials). Some patients had multiple amputations, some involving both lower limbs. Lower limb infections, gangrene, and diabetic foot ulcers were the most common precipitating medical events leading to the need for an amputation. The risk of amputation was highest in patients with a baseline history of prior amputation, peripheral vascular disease, and neuropathy. Counsel patients about the importance of routine preventative foot care. Monitor patients receiving INVOKAMET or INVOKAMET XR for signs and symptoms of infection (including osteomyelitis), new pain or tenderness, sores or ulcers involving the lower limbs, and discontinue INVOKAMET or INVOKAMET XR if these complications occur.

5.4 Volume Depletion Canagliflozin can cause intravascular volume contraction which may sometimes manifest as symptomatic hypotension or acute transient changes in creatinine <span class="opacity-50 text-xs">[see Adverse Reactions (6.1) ]</span> . There have been post-marketing reports of acute kidney injury which are likely related to volume depletion, some requiring hospitalizations and dialysis, in patients with type 2 diabetes mellitus receiving SGLT2 inhibitors, including canagliflozin. Patients with impaired renal function (eGFR less than 60 mL/min/1.73 m 2 ), elderly patients, or patients on loop diuretics may be at increased risk for volume depletion or hypotension. Before initiating INVOKAMET or INVOKAMET XR in patients with one or more of these characteristics, assess and correct volume status. Monitor for signs and symptoms of volume depletion after initiating therapy.

5.5 Urosepsis and Pyelonephritis There have been postmarketing reports of serious urinary tract infections including urosepsis and pyelonephritis requiring hospitalization in patients receiving canagliflozin. Treatment with INVOKAMET or INVOKAMET XR increases the risk for urinary tract infections. Evaluate patients for signs and symptoms of urinary tract infections and treat promptly, if indicated <span class="opacity-50 text-xs">[see Adverse Reactions (6) ]</span> .

5.6 Hypoglycemia with Concomitant Use with Insulin or Insulin Secretagogues Insulin and insulin secretagogues are known to cause hypoglycemia. INVOKAMET or INVOKAMET XR may increase the risk of hypoglycemia when combined with insulin or an insulin secretagogue <span class="opacity-50 text-xs">[see Adverse Reactions (6.1) ]</span> . The risk of hypoglycemia may be lowered by a reduction in the dose of sulfonylurea (or other concomitantly administered insulin secretagogues) or insulin. Inform patients using these concomitant medications of the risk of hypoglycemia and educate them on the signs and symptoms of hypoglycemia.

5.7 Necrotizing Fasciitis of the Perineum (Fournier&apos;s Gangrene) Reports of necrotizing fasciitis of the perineum (Fournier&apos;s gangrene), a rare but serious and life-threatening necrotizing infection requiring urgent surgical intervention, have been identified in postmarketing surveillance in patients with diabetes mellitus receiving SGLT2 inhibitors, including canagliflozin. Cases have been reported in both females and males. Serious outcomes have included hospitalization, multiple surgeries, and death. Patients treated with INVOKAMET or INVOKAMET XR presenting with pain or tenderness, erythema, or swelling in the genital or perineal area, along with fever or malaise, should be assessed for necrotizing fasciitis. If suspected, start treatment immediately with broad-spectrum antibiotics and, if necessary, surgical debridement. Discontinue INVOKAMET or INVOKAMET XR, closely monitor blood glucose levels, and provide appropriate alternative therapy for glycemic control.

5.8 Genital Mycotic Infections Canagliflozin increases the risk of genital mycotic infections. Patients with a history of genital mycotic infections and uncircumcised males were more likely to develop genital mycotic infections <span class="opacity-50 text-xs">[see Adverse Reactions (6.1) ]</span> . Monitor and treat appropriately.

5.9 Hypersensitivity Reactions Hypersensitivity reactions, including angioedema and anaphylaxis, have been reported with canagliflozin. These reactions generally occurred within hours to days after initiating canagliflozin. If hypersensitivity reactions occur, discontinue use of INVOKAMET or INVOKAMET XR; treat and monitor until signs and symptoms resolve <span class="opacity-50 text-xs">[see Contraindications (4) and Adverse Reactions (6.1 , 6.2) ]</span> .

5.10 Bone Fracture An increased risk of bone fracture, occurring as early as 12 weeks after treatment initiation, was observed in adult patients using canagliflozin in the CANVAS trial <span class="opacity-50 text-xs">[see Clinical Studies (14.3) ]</span> . Consider factors that contribute to fracture risk prior to initiating INVOKAMET or INVOKAMET XR <span class="opacity-50 text-xs">[see Adverse Reactions (6.1) ]</span> .

5.11 Vitamin B 12 Levels In metformin HCl clinical trials of 29-week duration, a decrease to subnormal levels of previously normal serum vitamin B 12 levels was observed in approximately 7% of patients. Such decrease, possibly due to interference with B 12 absorption from the B 12 -intrinsic factor complex, may be associated with anemia but appears to be rapidly reversible with discontinuation of metformin HCl or vitamin B 12 supplementation. Certain individuals (those with inadequate vitamin B 12 or calcium intake or absorption) appear to be predisposed to developing subnormal vitamin B 12 levels. Measure hematologic parameters on an annual basis and vitamin B 12 at 2- to 3-year intervals in patients on INVOKAMET or INVOKAMET XR and manage any abnormalities <span class="opacity-50 text-xs">[see Adverse Reactions (6.1) ]</span>.