TIGECYCLINE Drug Interactions: What You Need to Know

INTERACTIONS Warfarin : Suitable anticoagulation test should be monitored if tigecycline for injection is administered to patients receiving warfarin. (7.1)

Calcineurin

Inhibitors : Serum concentrations of calcineurin inhibitors (e.g., tacrolimus, cyclosporine) should be monitored during treatment with tigecycline for injection due to risk of toxicity. (7.2)

7.1 Warfarin Prothrombin time or other suitable anticoagulation test should be monitored if tigecycline for injection is administered with warfarin <span class="opacity-50 text-xs">[see Clinical Pharmacology (12.3) ]</span> .

7.2 Calcineurin Inhibitors Concomitant use of tigecycline for injection and calcineurin inhibitors such as tacrolimus or cyclosporine may lead to an increase in serum trough concentrations of the calcineurin inhibitors. Therefore, serum concentrations of the calcineurin inhibitor should be monitored during treatment with tigecycline for injection to avoid drug toxicity.

7.3 Oral Contraceptives Concurrent use of antibacterial drugs with oral contraceptives may render oral contraceptives less effective.

Tigecycline for injection is contraindicated for use in patients who have known hypersensitivity to tigecycline or to any of the excipients. Reactions have included anaphylactic reactions [ see Warnings and Precautions ( 5.3 ) and Adverse Reactions ( 6.2 ) ] . Known hypersensitivity to tigecycline. ( 4 )

AND PRECAUTIONS All-Cause Mortality : A meta-analysis of Phase 3 and 4 clinical trials demonstrated an increase in all-cause mortality in tigecycline-treated patients compared to controls with a risk difference of 0.6% (95% CI 0.1, 1.2). The cause of this increase has not been established. An increase was also seen in a meta-analysis limited to the approved indications [0.6% (95% CI 0, 1.2)]. The greatest difference in mortality was seen in tigecycline-treated patients with ventilator-associated pneumonia. ( 5.1 , 5.2 )

Anaphylactic

Reactions : have been reported with tigecycline, and may be life-threatening. Avoid use in patients with known hypersensitivity to tetracyclines. ( 5.3 )

Hepatic Adverse

Effects : have been reported with tigecycline. Patients who develop abnormal liver function tests during tigecycline therapy should be monitored for evidence of worsening hepatic function and evaluated for risk/benefit of continuing tigecycline therapy. ( 5.4 ) Pancreatitis : including fatalities, has been reported with tigecycline. If pancreatitis is suspected, then consider stopping tigecycline. ( 5.5 )

Fetal

Harm : Tigecycline may cause fetal harm when administered to a pregnant woman. ( 5.6 )

Tooth

Discoloration : The use of tigecycline during tooth development may cause permanent discoloration of the teeth. ( 5.7 ) Clostridium difficile- Associated Diarrhea (CDAD) : evaluate if diarrhea occurs. ( 5.8 )

5.1 All-Cause Mortality An increase in all-cause mortality has been observed in a meta-analysis of Phase 3 and 4 clinical trials in tigecycline-treated patients versus comparator-treated patients. In all 13 Phase 3 and 4 trials that included a comparator, death occurred in 4.0% (150/3,788) of patients receiving tigecycline and 3.0% (110/3,646) of patients receiving comparator drugs. In a pooled analysis of these trials, based on a random effects model by trial weight, the adjusted risk difference of all-cause mortality was 0.6% (95% CI 0.1, 1.2) between tigecycline and comparator-treated patients. An analysis of mortality in all trials conducted for approved indications (cSSSI, cIAI, and CABP), including post-market trials showed an adjusted mortality rate of 2.5% (66/2,640) for tigecycline and 1.8% (48/2,628) for comparator, respectively. The adjusted risk difference for mortality stratified by trial weight was 0.6% (95% CI 0.0, 1.2). The cause of this mortality difference has not been established. Generally, deaths were the result of worsening infection, complications of infection or underlying co-morbidities. Tigecycline should be reserved for use in situations when alternative treatments are not suitable <span class="opacity-50 text-xs">[see Boxed Warning, Indications and Usage ( 1.4 ), Warnings and Precautions ( 5.2 ) and Adverse Reactions ( 6.1 )]</span>.

5.2 Mortality Imbalance and Lower Cure Rates in Hospital-Acquired Pneumonia A trial of patients with hospital acquired, including ventilator-associated, pneumonia failed to demonstrate the efficacy of tigecycline. In this trial, patients were randomized to receive tigecycline (100 mg initially, then 50 mg every 12 hours) or a comparator. In addition, patients were allowed to receive specified adjunctive therapies. The sub-group of patients with ventilator-associated pneumonia who received tigecycline had lower cure rates (47.9% versus 70.1% for the clinically evaluable population). In this trial, greater mortality was seen in patients with ventilator-associated pneumonia who received tigecycline (25/131 [19.1%] versus 15/122 [12.3%] in comparator-treated patients) <span class="opacity-50 text-xs">[see Adverse Reactions ( 6.1 )]</span> . Particularly high mortality was seen among tigecycline-treated patients with ventilator-associated pneumonia and bacteremia at baseline (9/18 [50.0%] versus 1/13 [7.7%] in comparator-treated patients).

5.3 Anaphylactic Reactions Anaphylactic reactions have been reported with nearly all antibacterial agents, including tigecycline, and may be life-threatening. Tigecycline is structurally similar to tetracycline-class antibiotics and should be avoided in patients with known hypersensitivity to tetracycline-class antibiotics.

5.4 Hepatic Adverse Effects Increases in total bilirubin concentration, prothrombin time and transaminases have been seen in patients treated with tigecycline. Isolated cases of significant hepatic dysfunction and hepatic failure have been reported in patients being treated with tigecycline. Some of these patients were receiving multiple concomitant medications. Patients who develop abnormal liver function tests during tigecycline therapy should be monitored for evidence of worsening hepatic function and evaluated for risk/benefit of continuing tigecycline therapy. Hepatic dysfunction may occur after the drug has been discontinued.

5.5 Pancreatitis Acute pancreatitis, including fatal cases, has occurred in association with tigecycline treatment. The diagnosis of acute pancreatitis should be considered in patients taking tigecycline who develop clinical symptoms, signs, or laboratory abnormalities suggestive of acute pancreatitis. Cases have been reported in patients without known risk factors for pancreatitis. Patients usually improve after tigecycline discontinuation. Consideration should be given to the cessation of the treatment with tigecycline in cases suspected of having developed pancreatitis <span class="opacity-50 text-xs">[see Adverse Reactions (6.2) ]</span> .

5.6 Fetal Harm Tigecycline may cause fetal harm when administered to a pregnant woman. If the patient becomes pregnant while taking tigecycline, the patient should be apprised of the potential hazard to the fetus. Results of animal studies indicate that tigecycline crosses the placenta and is found in fetal tissues. Decreased fetal weights in rats and rabbits (with associated delays in ossification) and fetal loss in rabbits have been observed with tigecycline <span class="opacity-50 text-xs">[see Use in Specific Populations (8.1) ]</span> .

5.7 Tooth Discoloration The use of tigecycline during tooth development (last half of pregnancy, infancy, and childhood to the age of 8 years) may cause permanent discoloration of the teeth (yellow-gray-brown). Results of studies in rats with tigecycline have shown bone discoloration. Tigecycline should not be used during tooth development unless other drugs are not likely to be effective or are contraindicated.

5.8 Clostridium difficile - Associated Diarrhea Clostridium difficile associated diarrhea (CDAD) has been reported with use of nearly all antibacterial agents, including tigecycline, and may range in severity from mild diarrhea to fatal colitis. Treatment with antibacterial agents alters the normal flora of the colon leading to overgrowth of C. difficile . C. difficile produces toxins A and B which contribute to the development of CDAD. Hypertoxin producing strains of C. difficile cause increased morbidity and mortality, as these infections can be refractory to antimicrobial therapy and may require colectomy. CDAD must be considered in all patients who present with diarrhea following antibiotic use. Careful medical history is necessary since CDAD has been reported to occur over two months after the administration of antibacterial agents. If CDAD is suspected or confirmed, ongoing antibiotic use not directed against C. difficile may need to be discontinued. Appropriate fluid and electrolyte management, protein supplementation, antibiotic treatment of C. difficile , and surgical evaluation should be instituted as clinically indicated.

5.9 Sepsis/Septic Shock in Patients with Intestinal Perforation Monotherapy with tigecycline should be avoided in patients with complicated intra-abdominal infections (cIAI) secondary to clinically apparent intestinal perforation. In cIAI studies (n=1,642), 6 patients treated with tigecycline and 2 patients treated with imipenem/cilastatin presented with intestinal perforations and developed sepsis/septic shock.

The

6 patients treated with tigecycline had higher APACHE II scores (median = 13) versus the 2 patients treated with imipenem/cilastatin (APACHE II scores = 4 and 6). Due to differences in baseline APACHE II scores between treatment groups and small overall numbers, the relationship of this outcome to treatment cannot be established.

5.10 Tetracycline-Class Adverse Effects Tigecycline is structurally similar to tetracycline-class antibacterial drugs and may have similar adverse effects. Such effects may include: photosensitivity, pseudotumor cerebri, and anti-anabolic action (which has led to increased BUN, azotemia, acidosis, and hyperphosphatemia).

5.11 Development of Drug-Resistant Bacteria Prescribing tigecycline for injection in the absence of a proven or strongly suspected bacterial infection is unlikely to provide benefit to the patient and increases the risk of the development of drug-resistant bacteria.

5.1 All-Cause Mortality An increase in all-cause mortality has been observed in a meta-analysis of Phase 3 and 4 clinical trials in tigecycline-treated patients versus comparator-treated patients. In all 13 Phase 3 and 4 trials that included a comparator, death occurred in 4.0% (150/3,788) of patients receiving tigecycline and 3.0% (110/3,646) of patients receiving comparator drugs. In a pooled analysis of these trials, based on a random effects model by trial weight, the adjusted risk difference of all-cause mortality was 0.6% (95% CI 0.1, 1.2) between tigecycline and comparator-treated patients. An analysis of mortality in all trials conducted for approved indications (cSSSI, cIAI, and CABP), including post-market trials showed an adjusted mortality rate of 2.5% (66/2,640) for tigecycline and 1.8% (48/2,628) for comparator, respectively. The adjusted risk difference for mortality stratified by trial weight was 0.6% (95% CI 0.0, 1.2). The cause of this mortality difference has not been established. Generally, deaths were the result of worsening infection, complications of infection or underlying co-morbidities. Tigecycline should be reserved for use in situations when alternative treatments are not suitable <span class="opacity-50 text-xs">[see Boxed Warning, Indications and Usage ( 1.4 ), Warnings and Precautions ( 5.2 ) and Adverse Reactions ( 6.1 )]</span>.

5.2 Mortality Imbalance and Lower Cure Rates in Hospital-Acquired Pneumonia A trial of patients with hospital acquired, including ventilator-associated, pneumonia failed to demonstrate the efficacy of tigecycline. In this trial, patients were randomized to receive tigecycline (100 mg initially, then 50 mg every 12 hours) or a comparator. In addition, patients were allowed to receive specified adjunctive therapies. The sub-group of patients with ventilator-associated pneumonia who received tigecycline had lower cure rates (47.9% versus 70.1% for the clinically evaluable population). In this trial, greater mortality was seen in patients with ventilator-associated pneumonia who received tigecycline (25/131 [19.1%] versus 15/122 [12.3%] in comparator-treated patients) <span class="opacity-50 text-xs">[see Adverse Reactions ( 6.1 )]</span> . Particularly high mortality was seen among tigecycline-treated patients with ventilator-associated pneumonia and bacteremia at baseline (9/18 [50.0%] versus 1/13 [7.7%] in comparator-treated patients).

5.3 Anaphylactic Reactions Anaphylactic reactions have been reported with nearly all antibacterial agents, including tigecycline, and may be life-threatening. Tigecycline is structurally similar to tetracycline-class antibiotics and should be avoided in patients with known hypersensitivity to tetracycline-class antibiotics.

5.4 Hepatic Adverse Effects Increases in total bilirubin concentration, prothrombin time and transaminases have been seen in patients treated with tigecycline. Isolated cases of significant hepatic dysfunction and hepatic failure have been reported in patients being treated with tigecycline. Some of these patients were receiving multiple concomitant medications. Patients who develop abnormal liver function tests during tigecycline therapy should be monitored for evidence of worsening hepatic function and evaluated for risk/benefit of continuing tigecycline therapy. Hepatic dysfunction may occur after the drug has been discontinued.

5.5 Pancreatitis Acute pancreatitis, including fatal cases, has occurred in association with tigecycline treatment. The diagnosis of acute pancreatitis should be considered in patients taking tigecycline who develop clinical symptoms, signs, or laboratory abnormalities suggestive of acute pancreatitis. Cases have been reported in patients without known risk factors for pancreatitis. Patients usually improve after tigecycline discontinuation. Consideration should be given to the cessation of the treatment with tigecycline in cases suspected of having developed pancreatitis <span class="opacity-50 text-xs">[see Adverse Reactions (6.2) ]</span> .

5.6 Fetal Harm Tigecycline may cause fetal harm when administered to a pregnant woman. If the patient becomes pregnant while taking tigecycline, the patient should be apprised of the potential hazard to the fetus. Results of animal studies indicate that tigecycline crosses the placenta and is found in fetal tissues. Decreased fetal weights in rats and rabbits (with associated delays in ossification) and fetal loss in rabbits have been observed with tigecycline <span class="opacity-50 text-xs">[see Use in Specific Populations (8.1) ]</span> .

5.7 Tooth Discoloration The use of tigecycline during tooth development (last half of pregnancy, infancy, and childhood to the age of 8 years) may cause permanent discoloration of the teeth (yellow-gray-brown). Results of studies in rats with tigecycline have shown bone discoloration. Tigecycline should not be used during tooth development unless other drugs are not likely to be effective or are contraindicated.

5.8 Clostridium difficile - Associated Diarrhea Clostridium difficile associated diarrhea (CDAD) has been reported with use of nearly all antibacterial agents, including tigecycline, and may range in severity from mild diarrhea to fatal colitis. Treatment with antibacterial agents alters the normal flora of the colon leading to overgrowth of C. difficile . C. difficile produces toxins A and B which contribute to the development of CDAD. Hypertoxin producing strains of C. difficile cause increased morbidity and mortality, as these infections can be refractory to antimicrobial therapy and may require colectomy. CDAD must be considered in all patients who present with diarrhea following antibiotic use. Careful medical history is necessary since CDAD has been reported to occur over two months after the administration of antibacterial agents. If CDAD is suspected or confirmed, ongoing antibiotic use not directed against C. difficile may need to be discontinued. Appropriate fluid and electrolyte management, protein supplementation, antibiotic treatment of C. difficile , and surgical evaluation should be instituted as clinically indicated.

5.9 Sepsis/Septic Shock in Patients with Intestinal Perforation Monotherapy with tigecycline should be avoided in patients with complicated intra-abdominal infections (cIAI) secondary to clinically apparent intestinal perforation. In cIAI studies (n=1,642), 6 patients treated with tigecycline and 2 patients treated with imipenem/cilastatin presented with intestinal perforations and developed sepsis/septic shock.

The

6 patients treated with tigecycline had higher APACHE II scores (median = 13) versus the 2 patients treated with imipenem/cilastatin (APACHE II scores = 4 and 6). Due to differences in baseline APACHE II scores between treatment groups and small overall numbers, the relationship of this outcome to treatment cannot be established.

5.10 Tetracycline-Class Adverse Effects Tigecycline is structurally similar to tetracycline-class antibacterial drugs and may have similar adverse effects. Such effects may include: photosensitivity, pseudotumor cerebri, and anti-anabolic action (which has led to increased BUN, azotemia, acidosis, and hyperphosphatemia).

5.11 Development of Drug-Resistant Bacteria Prescribing tigecycline for injection in the absence of a proven or strongly suspected bacterial infection is unlikely to provide benefit to the patient and increases the risk of the development of drug-resistant bacteria.