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.
In clinical trials, 2,514 patients were treated with tigecycline. Tigecycline was discontinued due to adverse reactions in 7% of patients compared to 6% for all comparators. Table 1 shows the incidence of adverse reactions through test of cure reported in ≥ 2% of patients in these trials.
Table 1. Incidence (%) of Adverse Reactions Through Test of Cure
Reported in ≥ 2% of Patients Treated in Clinical Studies
Body System Adverse Reactions
| Tigecycline (N=2,514)
| Comparatorsa (N=2,307)
|
Body as a Whole
|
|
|
Abdominal pain
| 6
| 4
|
Abscess
| 2
| 2
|
Asthenia
| 3
| 2
|
Headache
| 6
| 7
|
Infection
| 7
| 5
|
Cardiovascular System
|
|
|
Phlebitis
| 3
| 4
|
Digestive System
|
|
|
Diarrhea
| 12
| 11
|
Dyspepsia
| 2
| 2
|
Nausea
| 26
| 13
|
Vomiting
| 18
| 9
|
Hemic and Lymphatic System
|
|
|
Anemia
| 5
| 6
|
Metabolic and Nutritional
|
|
|
Alkaline Phosphatase Increased
| 3
| 3
|
Amylase Increased
| 3
| 2
|
Bilirubinemia
| 2
| 1
|
BUN Increased
| 3
| 1
|
Healing Abnormal
| 3
| 2
|
Hyponatremia
| 2
| 1
|
Hypoproteinemia
| 5
| 3
|
SGOT Increasedb
| 4
| 5
|
SGPT Increasedb
| 5
| 5
|
Respiratory System
|
|
|
Pneumonia
| 2
| 2
|
Nervous System
|
|
|
Dizziness
| 3
| 3
|
Skin and Appendages
|
|
|
Rash
| 3
| 4
|
a Vancomycin/Aztreonam, Imipenem/Cilastatin, Levofloxacin, Linezolid.
b LFT abnormalities in tigecycline-treated patients were reported more frequently in the post therapy period
than those in comparator-treated patients, which occurred more often on therapy.
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, an adjusted risk difference of all-cause mortality was 0.6% (95% CI 0.1, 1.2) between tigecycline and comparator-treated patients (see Table 2). The cause of the imbalance has not been established. Generally, deaths were the result of worsening infection, complications of infection or underlying co-morbidities.
Table 2. Patients with Outcome of Death by Infection Type
| Tigecycline
| Comparator
| Risk Difference*
|
Infection Type
| n/N
| %
| n/N
| %
| % (95% CI)
|
cSSSI
| 12/834
| 1.4
| 6/813
| 0.7
| 0.7 (-0.3, 1.7)
|
cIAI
| 42/1,382
| 3.0
| 31/1,393
| 2.2
| 0.8 (-0.4, 2)
|
CAP
| 12/424
| 2.8
| 11/422
| 2.6
| 0.2 (-2, 2.4)
|
HAP
| 66/467
| 14.1
| 57/467
| 12.2
| 1.9 (-2.4, 6.3)
|
Non-VAPa
| 41/336
| 12.2
| 42/345
| 12.2
| 0.0 (-4.9, 4.9)
|
VAPa
| 25/131
| 19.1
| 15/122
| 12.3
| 6.8 (-2.1, 15.7)
|
RP
| 11/128
| 8.6
| 2/43
| 4.7
| 3.9 (-4, 11.9)
|
DFI
| 7/553
| 1.3
| 3/508
| 0.6
| 0.7 (-0.5, 1.8)
|
Overall Adjusted
| 150/3,788
| 4.0
| 110/3,646
| 3.0
| 0.6 (0.1, 1.2)**
|
CAP = Community-acquired pneumonia; cIAI = Complicated intra-abdominal infections;
cSSSI = Complicated skin and skin structure infections; HAP = Hospital-acquired pneumonia;
VAP = Ventilator-associated pneumonia; RP = Resistant pathogens; DFI = Diabetic foot infections.
* The difference between the percentage of patients who died in tigecycline and comparator treatment groups.
The 95% CI for each infection type was calculated using the normal approximation method without
continuity correction.
** Overall adjusted (random effects model by trial weight) risk difference estimate and 95% CI.
a These are subgroups of the HAP population.
Note: The studies include 300, 305, 900 (cSSSI), 301, 306, 315, 316, 400 (cIAI), 308 and 313 (CAP), 311 (HAP), 307 [Resistant gram-positive pathogen study in patients with MRSA or Vancomycin-Resistant Enterococcus (VRE)], and 319 (DFI with and without osteomyelitis).
An analysis of mortality in all trials conducted for approved indications - cSSSI, cIAI, and CABP, including post-market trials (one in cSSSI and two in cIAI) - 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).
In comparative clinical studies, infection-related serious adverse reactions were more frequently reported for subjects treated with tigecycline (7%) versus comparators (6%). Serious adverse reactions of sepsis/septic shock were more frequently reported for subjects treated with tigecycline (2%) versus comparators (1%). Due to baseline differences between treatment groups in this subset of patients, the relationship of this outcome to treatment cannot be established [see Warnings and Precautions (5.9)].
The most common adverse reactions were nausea and vomiting which generally occurred during the first 1 to 2 days of therapy. The majority of cases of nausea and vomiting associated with tigecycline and comparators were either mild or moderate in severity. In patients treated with tigecycline, nausea incidence was 26% (17% mild, 8% moderate, 1% severe) and vomiting incidence was 18% (11% mild, 6% moderate, 1% severe).
In patients treated for complicated skin and skin structure infections (cSSSI), nausea incidence was 35% for tigecycline and 9% for vancomycin/aztreonam; vomiting incidence was 20% for tigecycline and 4% for vancomycin/aztreonam. In patients treated for complicated intra-abdominal infections (cIAI), nausea incidence was 25% for tigecycline and 21% for imipenem/cilastatin; vomiting incidence was 20% for tigecycline and 15% for imipenem/cilastatin. In patients treated for community-acquired bacterial pneumonia (CABP), nausea incidence was 24% for tigecycline and 8% for levofloxacin; vomiting incidence was 16% for tigecycline and 6% for levofloxacin.
Discontinuation from tigecycline was most frequently associated with nausea (1%) and vomiting (1%). For comparators, discontinuation was most frequently associated with nausea (< 1%).
The following adverse reactions were reported (< 2%) in patients receiving tigecycline in clinical studies:
Body as a Whole: injection site inflammation, injection site pain, injection site reaction, septic shock, allergic reaction, chills, injection site edema, injection site phlebitis
Cardiovascular System: thrombophlebitis
Digestive System: anorexia, jaundice, abnormal stools
Metabolic/Nutritional System: increased creatinine, hypocalcemia, hypoglycemia
Special Senses: taste perversion
Hemic and Lymphatic System: partial thromboplastin time (aPTT), prolonged prothrombin time (PT), eosinophilia, increased international normalized ratio (INR), thrombocytopenia
Skin and Appendages: pruritus
Urogenital System: vaginal moniliasis, vaginitis, leukorrhea