- For IV infusion over a period of 30 minutes in adult patients: The appropriate volume of the reconstituted daptomycin for injection (concentration of 50 mg/mL) should be further diluted, using aseptic technique, into a 50 mL IV infusion bag containing 0.9% sodium chloride injection.
Pediatric Patients (1 to 17 Years of Age)
In-Use Storage Conditions for daptomycin for injection Once Reconstituted in Acceptable Intravenous Diluents
Stability studies have shown that the reconstituted solution is stable in the vial for 12 hours at room temperature and up to 48 hours if stored under refrigeration at 2°C to 8°C (36°F to 46°F).
The diluted solution is stable in the infusion bag for 12 hours at room temperature and 48 hours if stored under refrigeration. The combined storage time (reconstituted solution in vial and diluted solution in infusion bag) should not exceed 12 hours at room temperature or 48 hours under refrigeration.
Clinical Trial Experience in Adult Patients
Clinical trials enrolled 1,864 adult patients treated with daptomycin for injection and 1,416 treated with comparator.
Complicated Skin and Skin Structure Infection Trials in Adults
In Phase 3 complicated skin and skin structure infection (cSSSI) trials in adult patients, daptomycin for injection was discontinued in 15/534 (2.8%) patients due to an adverse reaction, while comparator was discontinued in 17/558 (3.0%) patients.
The rates of the most common adverse reactions, organized by body system, observed in adult patients with cSSSI (receiving 4 mg/kg daptomycin for injection) are displayed in Table 6.
Table 6: Incidence of Adverse Reactions that Occurred in ≥2% of Adult Patients in the daptomycin for injection Treatment Group and ≥ the Comparator Treatment Group in Phase 3 cSSSI Trials| Adverse Reaction | Adult Patients (%) |
|---|
Daptomycin for injection 4 mg/kg (N=534) | Comparator Comparator: vancomycin (1 g IV q12h) or an anti-staphylococcal semi-synthetic penicillin (i.e., nafcillin, oxacillin, cloxacillin, or flucloxacillin; 4 to 12 g/day IV in divided doses). (N=558) |
|---|
| Gastrointestinal disorders | | |
| Diarrhea | 5.2 | 4.3 |
| Nervous system disorders | | |
| Headache | 5.4 | 5.4 |
| Dizziness | 2.2 | 2.0 |
| Skin/subcutaneous disorders | | |
| Rash | 4.3 | 3.8 |
| Diagnostic investigations | | |
| Abnormal liver function tests | 3.0 | 1.6 |
| Elevated CPK | 2.8 | 1.8 |
| Infections | | |
| Urinary tract infections | 2.4 | 0.5 |
| Vascular disorders | | |
| Hypotension | 2.4 | 1.4 |
| Respiratory disorders | | |
| Dyspnea | 2.1 | 1.6 |
Drug-related adverse reactions (possibly or probably drug-related) that occurred in <1% of adult patients receiving daptomycin for injection in the cSSSI trials are as follows:
Body as a Whole: fatigue, weakness, rigors, flushing, hypersensitivity
Blood/Lymphatic System: leukocytosis, thrombocytopenia, thrombocytosis, eosinophilia, increased International Normalized Ratio (INR)
Cardiovascular System: supraventricular arrhythmia
Dermatologic System: eczema
Digestive System: abdominal distension, stomatitis, jaundice, increased serum lactate dehydrogenase
Metabolic/Nutritional System: hypomagnesemia, increased serum bicarbonate, electrolyte disturbance
Musculoskeletal System: myalgia, muscle cramps, muscle weakness, arthralgia
Nervous System: vertigo, mental status change, paresthesia
Special Senses: taste disturbance, eye irritation
S. aureus Bacteremia/Endocarditis Trial in Adults
In the S. aureus bacteremia/endocarditis trial involving adult patients, daptomycin for injection was discontinued in 20/120 (16.7%) patients due to an adverse reaction, while comparator was discontinued in 21/116 (18.1%) patients.
Serious Gram-negative infections (including bloodstream infections) were reported in 10/120 (8.3%) daptomycin for injection -treated patients and 0/115 comparator-treated patients. Comparator-treated patients received dual therapy that included initial gentamicin for 4 days. Infections were reported during treatment and during early and late follow-up. Gram-negative infections included cholangitis, alcoholic pancreatitis, sternal osteomyelitis/mediastinitis, bowel infarction, recurrent Crohn's disease, recurrent line sepsis, and recurrent urosepsis caused by a number of different Gram-negative bacteria.
The rates of the most common adverse reactions, organized by System Organ Class (SOC), observed in adult patients with S. aureus bacteremia/endocarditis (receiving 6 mg/kg daptomycin for injection) are displayed in Table 7.
Table 7: Incidence of Adverse Reactions that Occurred in ≥5% of Adult Patients in the daptomycin for injection Treatment Group and ≥ the Comparator Treatment Group in the S. aureus Bacteremia/Endocarditis Trial| Adverse Reaction NOS, not otherwise specified. | Adult Patients n (%) |
|---|
Daptomycin for injection 6 mg/kg (N=120) | Comparator Comparator: vancomycin (1 g IV q12h) or an anti-staphylococcal semi-synthetic penicillin (i.e., nafcillin, oxacillin, cloxacillin, or flucloxacillin; 2 g IV q4h), each with initial low-dose gentamicin. (N=116) |
|---|
| Infections and infestations | | |
| Sepsis NOS | 6 (5%) | 3 (3%) |
| Bacteremia | 6 (5%) | 0 (0%) |
| Gastrointestinal disorders | | |
| Abdominal pain NOS | 7 (6%) | 4 (3%) |
| General disorders and administration site conditions | | |
| Chest pain | 8 (7%) | 7 (6%) |
| Edema NOS | 8 (7%) | 5 (4%) |
| Respiratory, thoracic and mediastinal disorders | | |
| Pharyngolaryngeal pain | 10 (8%) | 2 (2%) |
| Skin and subcutaneous tissue disorders | | |
| Pruritus | 7 (6%) | 6 (5%) |
| Sweating increased | 6 (5%) | 0 (0%) |
| Psychiatric disorders | | |
| Insomnia | 11 (9%) | 8 (7%) |
| Investigations | | |
| Blood creatine phosphokinase increased | 8 (7%) | 1 (1%) |
| Vascular disorders | | |
| Hypertension NOS | 7 (6%) | 3 (3%) |
The following reactions, not included above, were reported as possibly or probably drug-related in the daptomycin-treated group:
Blood and Lymphatic System Disorders: eosinophilia, lymphadenopathy, thrombocythemia, thrombocytopenia
Cardiac Disorders: atrial fibrillation, atrial flutter, cardiac arrest
Ear and Labyrinth Disorders: tinnitus
Eye Disorders: vision blurred
Gastrointestinal Disorders: dry mouth, epigastric discomfort, gingival pain, hypoesthesia oral
Infections and Infestations: candidal infection NOS, vaginal candidiasis, fungemia, oral candidiasis, urinary tract infection fungal
Investigations: blood phosphorous increased, blood alkaline phosphatase increased, INR increased, liver function test abnormal, alanine aminotransferase increased, aspartate aminotransferase increased, prothrombin time prolonged
Metabolism and Nutrition Disorders: appetite decreased NOS
Musculoskeletal and Connective Tissue Disorders: myalgia
Nervous System Disorders: dyskinesia, paresthesia
Psychiatric Disorders: hallucination NOS
Renal and Urinary Disorders: proteinuria, renal impairment NOS
Skin and Subcutaneous Tissue Disorders: pruritus generalized, rash vesicular
Other Trials in Adults
In Phase 3 trials of community-acquired pneumonia (CAP) in adult patients, the death rate and rates of serious cardiorespiratory adverse events were higher in daptomycin for injection-treated patients than in comparator-treated patients. These differences were due to lack of therapeutic effectiveness of daptomycin for injection in the treatment of CAP in patients experiencing these adverse events [see Indications and Usage (1.4)].
Laboratory Changes in Adults
Complicated Skin and Skin Structure Infection Trials in Adults
In Phase 3 cSSSI trials of adult patients receiving daptomycin for injection at a dose of 4 mg/kg, elevations in CPK were reported as clinical adverse events in 15/534 (2.8%) daptomycin for injection -treated patients, compared with 10/558 (1.8%) comparator-treated patients. Of the 534 patients treated with daptomycin for injection, 1 (0.2%) had symptoms of muscle pain or weakness associated with CPK elevations to greater than 4 times the upper limit of normal (ULN). The symptoms resolved within 3 days and CPK returned to normal within 7 to 10 days after treatment was discontinued [see Warnings and Precautions (5.2)]. Table 8 summarizes the CPK shifts from Baseline through End of Therapy in the cSSSI adult trials.
Table 8: Incidence of CPK Elevations from Baseline during Therapy in Either the daptomycin for injection Treatment Group or the Comparator Treatment Group in Phase 3 cSSSI Adult Trials| Change in CPK | All Adult Patients | Adult Patients with Normal CPK at Baseline |
|---|
Daptomycin for injection 4 mg/kg (N=430) | Comparator Comparator: vancomycin (1 g IV q12h) or an anti-staphylococcal semi-synthetic penicillin (i.e., nafcillin, oxacillin, cloxacillin, or flucloxacillin; 4 to 12 g/day IV in divided doses). (N=459) | Daptomycin for injection 4 mg/kg (N=374) | Comparator* (N=392) |
|---|
| % | n | % | n | % | n | % | n |
|---|
| Note: Elevations in CPK observed in adult patients treated with daptomycin for injection or comparator were not clinically or statistically significantly different. |
| No Increase | | 90.7 | 390 | 91.1 | 418 | 91.2 | 341 | 91.1 | 357 |
| Maximum Value | >1× ULN ULN (Upper Limit of Normal) is defined as 200 U/L. | 9.3 | 40 | 8.9 | 41 | 8.8 | 33 | 8.9 | 35 |
| >2× ULN | 4.9 | 21 | 4.8 | 22 | 3.7 | 14 | 3.1 | 12 |
| >4× ULN | 1.4 | 6 | 1.5 | 7 | 1.1 | 4 | 1.0 | 4 |
| >5× ULN | 1.4 | 6 | 0.4 | 2 | 1.1 | 4 | 0.0 | 0 |
| >10× ULN | 0.5 | 2 | 0.2 | 1 | 0.2 | 1 | 0.0 | 0 |
S. aureus Bacteremia/Endocarditis Trial in Adults
In the S. aureus bacteremia/endocarditis trial in adult patients, at a dose of 6 mg/kg, 11/120 (9.2%) daptomycin for injection -treated patients, including two patients with baseline CPK levels >500 U/L, had CPK elevations to levels >500 U/L, compared with 1/116 (0.9%) comparator-treated patients. Of the 11 daptomycin for injection -treated patients, 4 had prior or concomitant treatment with an HMG-CoA reductase inhibitor. Three of these 11 daptomycin for injection-treated patients discontinued therapy due to CPK elevation, while the one comparator-treated patient did not discontinue therapy [see Warnings and Precautions (5.2)].
Clinical Trial Experience in Pediatric Patients
Complicated Skin and Skin Structure Infection Trial in Pediatric Patients
The safety of daptomycin for injection was evaluated in one clinical trial (in cSSSI), which included 256 pediatric patients (1 to 17 years of age) treated with intravenous daptomycin for injection and 133 patients treated with comparator agents. Patients were given age-dependent doses once daily for a treatment period of up to 14 days (median treatment period was 3 days). The doses given by age group were as follows: 10mg/kg for 1 to < 2 years, 9 mg/kg for 2 to 6 years, 7mg/kg for 7 to 11 years and 5 mg/kg for 12 to 17 years of age [see Clinical Studies (14)]. Patients treated with daptomycin for injection were (51%) male, (49%) female and (46%) Caucasian and (32%) Asian.
Adverse Reactions Leading to Discontinuation
In the cSSSI study, daptomycin for injection was discontinued in 7/256 (2.7%) patients due to an adverse reaction, while comparator was discontinued in 7/133 (5.3%) patients.
Most Common Adverse Reactions
The rates of the most common adverse reactions, organized by body system, observed in these pediatric patients with cSSSI are displayed in Table 9.
Table 9: Adverse Reactions that Occurred in ≥2% of Pediatric Patients in the daptomycin for injection Treatment-Arm and Greater Than or Equal to the Comparator Treatment-Arm in the cSSSI Pediatric Trial | Daptomycin for injection (N = 256) | Comparator (N = 133) |
|---|
| Adverse Reaction | n (%) | n (%) |
|---|
| Gastrointestinal disorders | | |
| Diarrhea | 18 (7.0) | 7 (5.3) |
| Vomiting | 7 (2.7) | 1 (0.8) |
| Abdominal Pain | 5 (2.0) | 0 |
| Skin and subcutaneous tissue disorders | | |
| Pruritus | 8 (3.1) | 2 (1.5) |
| General disorders and administration site conditions | | |
| Pyrexia | 10 (3.9) | 4 (3.0) |
| Investigations | | |
| Blood CPK increased | 14 (5.5) | 7 (5.3) |
| Nervous system disorders | | |
| Headache | 7 (2.7) | 3 (2.3) |
The safety profile in the clinical trial of cSSSI pediatric patients was similar to that observed in the cSSSI adult patients.
S. aureus Bacteremia Trial in Pediatric Patients
The safety of daptomycin for injection was evaluated in one clinical trial (in S. aureus bacteremia), which treated 55 pediatric patients with intravenous daptomycin for injection and 26 patients with comparator agents. Patients were given age-dependent doses once daily for a treatment period of up to 42 days (mean duration of IV treatment was 12 days). The doses by age group were as follows: 12 mg/kg for 1 to <6 years, 9 mg/kg for 7 to 11 years and 7 mg/kg for 12 to 17 years of age [see Clinical Studies (14)]. Patients treated with daptomycin were (69%) male and (31%) female. No patients 1 to <2 years of age were enrolled.
Adverse Reactions Leading to Discontinuation
In the bacteremia study, daptomycin for injection was discontinued in 3/55 (5.5%) patients due to an adverse reaction, while comparator was discontinued in 2/26 (7.7%) patients.
Most Common Adverse Reactions
The rates of the most common adverse reactions, organized by body system, observed in these pediatric patients with bacteremia are displayed in Table 10.
Table 10: Incidence of Adverse Reactions that Occurred in ≥5% of Pediatric Patients in the daptomycin for injection Treatment-Arm and Greater Than or Equal to the Comparator Treatment-Arm in the Pediatric Bacteremia Trial | Daptomycin for injection (N = 55) | Comparator (N = 26) |
|---|
| Adverse Reaction | n (%) | n (%) |
|---|
| *Comparators included intravenous therapy with either vancomycin, cefazolin, or an anti-staphylococcal semi-synthetic penicillin (nafcillin, oxacillin or cloxacillin) |
| Gastrointestinal disorders | | |
| Vomiting | 6 (10.9) | 2 (7.7) |
| Investigations | | |
| Blood CPK increased | 4 (7.3) | 0 |
Risk Summary
Limited published data on use of daptomycin for injection in pregnant women are insufficient to inform a drug-associated risk for major birth defects and miscarriage. In animal reproduction studies performed in rats and rabbits daptomycin was administered intravenously during organogenesis at doses 2 and 4-times, respectively, the recommended 6 mg/kg human dose (on a body surface area basis). No evidence of adverse developmental outcomes was observed.
The background risk of major birth defects and miscarriage for the indicated population is unknown. All pregnancies have a background risk of birth defect, loss, or other adverse outcomes. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2-4% and 15-20%, respectively.
Data
Animal Data
In pregnant rats, daptomycin was administered intravenously at doses of 5, 20, or 75 mg/kg/day during the gestation days 6 to 18. Maternal body weight gain was decreased at 75 mg/kg/day. No embryo/fetal effects were noted at the highest dose of 75 mg/kg/day, a dose approximately 2-fold higher than in humans at the recommended maximum dose of 6mg/kg (based on body surface area).
In pregnant rabbits, daptomycin was administered intravenously at doses of 5, 20, or 75 mg/kg/day during the gestation days 6 to 15. Maternal body weight gain and food consumption were decreased at 75 mg/kg/day. No embryo/fetal effects were noted at the highest dose of 75 mg/kg/day, a dose approximately 4-fold higher than in humans at the maximum recommended dose of 6mg/kg (based on body surface area).
In a combined fertility and pre/postnatal development study, daptomycin was administered intravenously to female rats at doses of 2, 25, 75 mg/kg/day from 14-days pre-mating through lactation/postpartum day 20). No effects on pre/postnatal development were observed up to the highest dose of 75 mg/kg/day, a dose approximately 2-fold higher than the maximum recommended human dose of 6 mg/kg (based on body surface area)1.
Risk Summary
Limited published data report that daptomycin is present in human milk at infant doses of 0.1% of the maternal dose (see Data)2,3,4. There is no information on the effects of daptomycin on the breastfed infant or the effects of daptomycin on milk production. The developmental and health benefits of breastfeeding should be considered along with the mother's clinical need for daptomycin for injection and any potential adverse effects on the breastfed infant from daptomycin for injection or from the underlying maternal condition.
Daptomycin for injection Administered over a 30-Minute Period in Adults
The mean and standard deviation (SD) pharmacokinetic parameters of daptomycin at steady-state following intravenous (IV) administration of daptomycin for injection over a 30-minute period at 4 to 12 mg/kg every 24h to healthy young adults are summarized in Table 11.
Table 11: Mean (SD) Daptomycin Pharmacokinetic Parameters in Healthy Adult Volunteers at Steady-State| Dose Daptomycin for injection was administered by IV infusion over a 30-minute period. Doses of daptomycin for injection in excess of 6 mg/kg have not been approved. (mg/kg) | Pharmacokinetic Parameters AUC0-24, area under the concentration-time curve from 0 to 24 hours; t1/2, elimination half-life; Vss, volume of distribution at steady-state; CLT, total plasma clearance; Cmax, maximum plasma concentration. |
|---|
AUC0-24 (mcg∙h/mL) | t1/2 (h) | Vss (L/kg) | CLT (mL/h/kg) | Cmax (mcg/mL) |
|---|
| 4 (N=6) | 494 (75) | 8.1 (1.0) | 0.096 (0.009) | 8.3 (1.3) | 57.8 (3.0) |
| 6 (N=6) | 632 (78) | 7.9 (1.0) | 0.101 (0.007) | 9.1 (1.5) | 93.9 (6.0) |
| 8 (N=6) | 858 (213) | 8.3 (2.2) | 0.101 (0.013) | 9.0 (3.0) | 123.3 (16.0) |
| 10 (N=9) | 1039 (178) | 7.9 (0.6) | 0.098 (0.017) | 8.8 (2.2) | 141.1 (24.0) |
| 12 (N=9) | 1277 (253) | 7.7 (1.1) | 0.097 (0.018) | 9.0 (2.8) | 183.7 (25.0) |
Daptomycin pharmacokinetics were generally linear and time-independent at daptomycin for injection doses of 4 to 12 mg/kg every 24h administered by IV infusion over a 30-minute period for up to 14 days. Steady-state trough concentrations were achieved by the third daily dose. The mean (SD) steady-state trough concentrations attained following the administration of 4, 6, 8, 10, and 12 mg/kg every 24h were 5.9 (1.6), 6.7 (1.6), 10.3 (5.5), 12.9 (2.9), and 13.7 (5.2) mcg/mL, respectively.
Daptomycin for injection Administered over a 2-Minute Period in Adults
Following IV administration of daptomycin for injection over a 2-minute period to healthy adult volunteers at doses of 4 mg/kg (N=8) and 6 mg/kg (N=12), the mean (SD) steady-state systemic exposure (AUC) values were 475 (71) and 701 (82) mcg∙h/mL, respectively. Values for maximum plasma concentration (Cmax) at the end of the 2-minute period could not be determined adequately in this study. However, using pharmacokinetic parameters from 14 healthy adult volunteers who received a single dose of daptomycin for injection 6 mg/kg IV administered over a 30-minute period in a separate study, steady-state Cmax values were simulated for daptomycin 4 and 6 mg/kg IV administered over a 2-minute period. The simulated mean (SD) steady-state Cmax values were 77.7 (8.1) and 116.6 (12.2) mcg/mL, respectively.
Distribution
Daptomycin is reversibly bound to human plasma proteins, primarily to serum albumin, in a concentration-independent manner. The overall mean binding ranges from 90 to 93%.
In clinical studies, mean serum protein binding in adult subjects with creatinine clearance (CLCR) ≥30 mL/min was comparable to that observed in healthy adult subjects with normal renal function. However, there was a trend toward decreasing serum protein binding among subjects with CLCR <30 mL/min (88%), including those receiving hemodialysis (86%) and continuous ambulatory peritoneal dialysis (CAPD) (84%). The protein binding of daptomycin in adult subjects with moderate hepatic impairment (Child-Pugh Class B) was similar to that in healthy adult subjects.
The volume of distribution at steady-state (Vss) of daptomycin in healthy adult subjects was approximately 0.1 L/kg and was independent of dose.
Metabolism
In in vitro studies, daptomycin was not metabolized by human liver microsomes.
In 5 healthy adults after infusion of radiolabeled 14C-daptomycin, the plasma total radioactivity was similar to the concentration determined by microbiological assay. Inactive metabolites were detected in urine, as determined by the difference between total radioactive concentrations and microbiologically active concentrations. In a separate study, no metabolites were observed in plasma on Day 1 following the administration of daptomycin for injection at 6 mg/kg to adult subjects. Minor amounts of three oxidative metabolites and one unidentified compound were detected in urine. The site of metabolism has not been identified.
Excretion
Daptomycin is excreted primarily by the kidneys. In a mass balance study of 5 healthy adult subjects using radiolabeled daptomycin, approximately 78% of the administered dose was recovered from urine based on total radioactivity (approximately 52% of the dose based on microbiologically active concentrations), and 5.7% of the administered dose was recovered from feces (collected for up to 9 days) based on total radioactivity.
Specific Populations
Patients with Renal Impairment
Population-derived pharmacokinetic parameters were determined for infected adult patients (complicated skin and skin structure infections [cSSSI] and S. aureus bacteremia) and noninfected adult subjects with various degrees of renal function (Table 12). Total plasma clearance (CLT), elimination half-life (t1/2), and volume of distribution at steady-state (Vss) in patients with cSSSI were similar to those in patients with S. aureus bacteremia. Following administration of daptomycin for injection 4 mg/kg every 24h by IV infusion over a 30-minute period, the mean CLT was 9%, 22%, and 46% lower among subjects and patients with mild (CLCR 50–80 mL/min), moderate (CLCR 30–<50 mL/min), and severe (CLCR <30 mL/min) renal impairment, respectively, than in those with normal renal function (CLCR >80 mL/min). The mean steady-state systemic exposure (AUC), t1/2, and Vss increased with decreasing renal function, although the mean AUC for patients with CLCR 30–80 mL/min was not markedly different from the mean AUC for patients with normal renal function. The mean AUC for patients with CLCR <30 mL/min and for patients on dialysis (CAPD and hemodialysis dosed post-dialysis) was approximately 2 and 3 times higher, respectively, than for patients with normal renal function. The mean Cmax ranged from 60 to 70 mcg/mL in patients with CLCR ≥30 mL/min, while the mean Cmax for patients with CLCR <30 mL/min ranged from 41 to 58 mcg/mL. After administration of daptomycin for injection 6 mg/kg every 24h by IV infusion over a 30-minute period, the mean Cmax ranged from 80 to 114 mcg/mL in patients with mild to moderate renal impairment and was similar to that of patients with normal renal function.
Table 12: Mean (SD) Daptomycin Population Pharmacokinetic Parameters Following Infusion of daptomycin for injection 4 mg/kg or 6 mg/kg to Infected Adult Patients and Noninfected Adult Subjects with Various Degrees of Renal Function| Renal Function | Pharmacokinetic Parameters CLCR, creatinine clearance estimated using the Cockcroft-Gault equation with actual body weight; CAPD, continuous ambulatory peritoneal dialysis; AUC0-∞, area under the concentration-time curve extrapolated to infinity; AUCss, area under the concentration-time curve calculated over the 24-hour dosing interval at steady-state; Cmin,ss, trough concentration at steady-state; NA, not applicable. |
|---|
| t1/2 Parameters obtained following a single dose from patients with complicated skin and skin structure infections and healthy subjects. (h) 4 mg/kg | Vss (L/kg) 4 mg/kg | CLT (mL/h/kg) 4 mg/kg | AUC0-∞ (mcg∙h/mL) 4 mg/kg | AUCss Parameters obtained at steady-state from patients with S. aureus bacteremia. (mcg∙h/mL) 6 mg/kg | Cmin,ss‡ (mcg/mL) 6 mg/kg |
|---|
| Note: Daptomycin for injection was administered over a 30-minute period. |
Normal (CLCR >80 mL/min) | 9.39 (4.74) N=165 | 0.13 (0.05) N=165 | 10.9 (4.0) N=165 | 417 (155) N=165 | 545 (296) N=62 | 6.9 (3.5) N=61 |
Mild Renal Impairment (CLCR 50–80 mL/min) | 10.75 (8.36) N=64 | 0.12 (0.05) N=64 | 9.9 (4.0) N=64 | 466 (177) N=64 | 637 (215) N=29 | 12.4 (5.6) N=29 |
Moderate Renal Impairment (CLCR 30–<50 mL/min) | 14.70 (10.50) N=24 | 0.15 (0.06) N=24 | 8.5 (3.4) N=24 | 560 (258) N=24 | 868 (349) N=15 | 19.0 (9.0) N=14 |
Severe Renal Impairment (CLCR <30 mL/min) | 27.83 (14.85) N=8 | 0.20 (0.15) N=8 | 5.9 (3.9) N=8 | 925 (467) N=8 | 1050 (892) N=2 | 24.4 (21.4) N=2 |
| Hemodialysis | 30.51 (6.51) N=16 | 0.16 (0.04) N=16 | 3.9 (2.1) N=16 | 1193 (399) N=16 | NA | NA |
| CAPD | 27.56 (4.53) N=5 | 0.11 (0.02) N=5 | 2.9 (0.4) N=5 | 1409 (238) N=5 | NA | NA |
Because renal excretion is the primary route of elimination, adjustment of daptomycin for injection dosage interval is necessary in adult patients with severe renal impairment (CLCR <30 mL/min) [see Dosage and Administration (2.6)].
Patients with Hepatic Impairment
The pharmacokinetics of daptomycin were evaluated in 10 adult subjects with moderate hepatic impairment (Child-Pugh Class B) and compared with those in healthy adult volunteers (N=9) matched for gender, age, and weight. The pharmacokinetics of daptomycin were not altered in subjects with moderate hepatic impairment. No dosage adjustment is warranted when daptomycin for injection is administered to patients with mild to moderate hepatic impairment. The pharmacokinetics of daptomycin in patients with severe hepatic impairment (Child-Pugh Class C) have not been evaluated.
Gender
No clinically significant gender-related differences in daptomycin pharmacokinetics have been observed. No dosage adjustment is warranted based on gender when daptomycin for injection is administered.
Geriatric Patients
The pharmacokinetics of daptomycin were evaluated in 12 healthy elderly subjects (≥75 years of age) and 11 healthy young adult controls (18 to 30 years of age). Following administration of a single 4 mg/kg dose of daptomycin for injection by IV infusion over a 30-minute period, the mean total clearance of daptomycin was approximately 35% lower and the mean AUC0-∞ was approximately 58% higher in elderly subjects than in healthy young adult subjects. There were no differences in Cmax [see Use in Specific Populations (8.5)].
Obese Patients
The pharmacokinetics of daptomycin were evaluated in 6 moderately obese (Body Mass Index [BMI] 25 to 39.9 kg/m2) and 6 extremely obese (BMI ≥40 kg/m2) adult subjects and controls matched for age, gender, and renal function. Following administration of daptomycin for injection by IV infusion over a 30-minute period as a single 4 mg/kg dose based on total body weight, the total plasma clearance of daptomycin normalized to total body weight was approximately 15% lower in moderately obese subjects and 23% lower in extremely obese subjects than in nonobese controls. The AUC0-∞ of daptomycin was approximately 30% higher in moderately obese subjects and 31% higher in extremely obese subjects than in nonobese controls. The differences were most likely due to differences in the renal clearance of daptomycin. No adjustment of daptomycin for injection dosage is warranted in obese patients.
Pediatric Patients
The pharmacokinetics of daptomycin in pediatric subjects was evaluated in 3 single-dose pharmacokinetic studies. In general, body weight-normalized total body clearance in pediatric patients was higher than in adults and increased with a decrease of age, whereas elimination half-life tends to decrease with a decrease of age. Body weight-normalized total body clearance and elimination half-life of daptomycin in children 2 to 6 years of age were similar at different doses.
A study was conducted to assess safety, efficacy, and pharmacokinetics of daptomycin in pediatric patients (1 to 17 years old, inclusive) with cSSSI caused by Gram-positive pathogens. Patients were enrolled into 4 age groups [see Clinical Studies (14.1)], and intravenous daptomycin for injection doses of 5 to 10 mg/kg once daily were administered. Following administration of multiple doses, daptomycin exposure (AUCss and Cmax,ss) was similar across different age groups after dose adjustment based on body weight and age (Table 13).
Table 13: Mean (SD) Daptomycin Population Pharmacokinetic Parameters in cSSSI Pediatric Patients| Age | Pharmacokinetic Parameters |
|---|
Dose (mg/kg) | Infusion Duration (min) | AUCss (mcg∙h/mL) | t1/2 (h) | Vss (mL) | CLT (mL/h/kg) | Cmax,ss (mcg/mL) |
|---|
| AUCss, area under the concentration-time curve at steady state; CLT, clearance normalized to body weight; Vss, volume of distribution at steady state; t½, terminal half-life |
12 to 17 years (N=6) | 5 | 30 | 434 (67.9) | 7.1 (0.9) | 8200 (3250) | 11.8 (2.15) | 76.4 (6.75) |
7 to 11 years (N=2) | 7 | 30 | 543 | 6.8* | 4470* | 13.2* | 92.4* |
2 to 6 years (N=7) | 9 | 60 | 452 (93.1) | 4.6 (0.8) | 2750 (832) | 20.8 (4.29) | 90.3 (14.0) |
1 to less than 2 years (N=27) | 10 | 60 | 462 (138) | 4.8 (0.6) | 1670 (446) | 23.1 (5.43) | 81.6 (20.7) |
A study was conducted to assess safety, efficacy, and pharmacokinetics of daptomycin in pediatric patients with S. aureus bacteremia. Patients were enrolled into 3 age groups [see Clinical Studies (14.2)], and intravenous doses of 7 to 12 mg/kg once daily were administered. Following administration of multiple doses, daptomycin exposure (AUCss and Cmax,ss) was similar across different age groups after dose adjustment based on body weight and age (Table 14).
Table 14: Mean (SD) of Daptomycin Pharmacokinetics in Bacteremia Pediatric Patients| Age | Pharmacokinetic Parameters |
|---|
Dose (mg/kg) | Infusion Duration (min) | AUCss (mcg∙h/mL) | t1/2 (h) | Vss (mL) | CLT (mL/h/kg) | Cmax,ss (mcg/mL) |
|---|
AUCss, area under the concentration-time curve at steady state; CLT, clearance normalized to body weight; Vss, volume of distribution at steady state; t½, terminal half-life. No patients 1 to <2 years of age were enrolled in the study. Simulation using a population pharmacokinetic model demonstrated that the AUCss of daptomycin in pediatric patients 1 to <2 years of age receiving 12 mg/kg once daily would be comparable to that in adult patients receiving 6 mg/kg once daily. |
12 to 17 years (N=13) | 7 | 30 | 656 (334) | 7.5 (2.3) | 6420 (1980) | 12.4 (3.9) | 104 (35.5) |
7 to 11 years (N=19) | 9 | 30 | 579 (116) | 6.0 (0.8) | 4510 (1470) | 15.9 (2.8) | 104 (14.5) |
2 to 6 years (N=19) | 12 | 60 | 620 (109) | 5.1 (0.6) | 2200 (570) | 19.9 (3.4) | 106 (12.8) |
Drug Interaction Studies
In Vitro Studies
In vitro studies with human hepatocytes indicate that daptomycin does not inhibit or induce the activities of the following human cytochrome P450 isoforms: 1A2, 2A6, 2C9, 2C19, 2D6, 2E1, and 3A4. It is unlikely that daptomycin will inhibit or induce the metabolism of drugs metabolized by the P450 system.
Aztreonam
In a study in which 15 healthy adult subjects received a single dose of daptomycin for injection 6 mg/kg IV and a combination dose of daptomycin for injection 6 mg/kg IV and aztreonam 1 g IV, administered over a 30-minute period, the Cmax and AUC0-∞ of daptomycin were not significantly altered by aztreonam.
Tobramycin
In a study in which 6 healthy adult males received a single dose of daptomycin for injection 2 mg/kg IV, tobramycin 1 mg/kg IV, and both in combination, administered over a 30-minute period, the mean Cmax and AUC0-∞ of daptomycin were 12.7% and 8.7% higher, respectively, when daptomycin for injection was coadministered with tobramycin. The mean Cmax and AUC0-∞ of tobramycin were 10.7% and 6.6% lower, respectively, when tobramycin was coadministered with daptomycin for injection. These differences were not statistically significant. The interaction between daptomycin and tobramycin with a clinical dose of daptomycin for injection is unknown.
Warfarin
In 16 healthy adult subjects, administration of daptomycin for injection 6 mg/kg every 24h by IV infusion over a 30-minute period for 5 days, with coadministration of a single oral dose of warfarin (25 mg) on the 5th day, had no significant effect on the pharmacokinetics of either drug and did not significantly alter the INR (International Normalized Ratio).
Simvastatin
In 20 healthy adult subjects on a stable daily dose of simvastatin 40 mg, administration of daptomycin for injection 4 mg/kg every 24h by IV infusion over a 30-minute period for 14 days (N=10) had no effect on plasma trough concentrations of simvastatin and was not associated with a higher incidence of adverse events, including skeletal myopathy, than in subjects receiving placebo once daily (N=10) [see Warnings and Precautions (5.2) and Drug Interactions (7.1)].
Probenecid
Concomitant administration of probenecid (500 mg 4 times daily) and a single dose of daptomycin for injection 4 mg/kg by IV infusion over a 30-minute period in adults did not significantly alter the Cmax or AUC0-∞ of daptomycin.
Mechanism of Action
Daptomycin binds to bacterial cell membranes and causes a rapid depolarization of membrane potential. This loss of membrane potential causes inhibition of DNA, RNA, and protein synthesis, which results in bacterial cell death.
Resistance
The mechanism(s) of daptomycin resistance is not fully understood. Currently, there are no known transferable elements that confer resistance to daptomycin.
Interactions with Other Antibacterials
In vitro studies have investigated daptomycin interactions with other antibacterials. Antagonism, as determined by kill curve studies, has not been observed. In vitro synergistic interactions of daptomycin with aminoglycosides, β-lactam antibacterials, and rifampin have been shown against some isolates of staphylococci (including some methicillin-resistant isolates) and enterococci (including some vancomycin-resistant isolates).
Complicated Skin and Skin Structure Infection (cSSSI) Trials in Adults
The emergence of daptomycin non-susceptible isolates occurred in 2 infected patients across the set of Phase 2 and pivotal Phase 3 clinical trials of cSSSI in adult patients. In one case, a non-susceptible S. aureus was isolated from a patient in a Phase 2 trial who received daptomycin for injection at less than the protocol-specified dose for the initial 5 days of therapy. In the second case, a non-susceptible Enterococcus faecalis was isolated from a patient with an infected chronic decubitus ulcer who was enrolled in a salvage trial.
S. aureus Bacteremia/Endocarditis and Other Post-Approval Trials in Adults
In subsequent clinical trials in adult patients, non-susceptible isolates were recovered. S. aureus was isolated from a patient in a compassionate-use trial and from 7 patients in the S. aureus bacteremia/endocarditis trial [see Clinical Studies (14.2)]. An E. faecium was isolated from a patient in a vancomycin-resistant enterococci trial.
Antimicrobial Activity
Daptomycin has been shown to be active against most isolates of the following microorganisms both in vitro and in clinical infections [see Indications and Usage (1)].
- Gram-Positive Bacteria
- Enterococcus faecalis (vancomycin-susceptible isolates only)
- Staphylococcus aureus (including methicillin-resistant isolates)
- Streptococcus agalactiae
- Streptococcus dysgalactiae subsp. equisimilis
- Streptococcus pyogenes
The following in vitro data are available, but their clinical significance is unknown. At least 90 percent of the following bacteria exhibit an in vitro minimum inhibitory concentration (MIC) less than or equal to the susceptible breakpoint for daptomycin against isolates of similar genus or organism group. However, the efficacy of daptomycin in treating clinical infections caused by these bacteria has not been established in adequate and well-controlled clinical trials.
- Gram-Positive Bacteria
- Corynebacterium jeikeium
- Enterococcus faecalis (vancomycin-resistant isolates)
- Enterococcus faecium (including vancomycin-resistant isolates)
- Staphylococcus epidermidis (including methicillin-resistant isolates)
- Staphylococcus haemolyticus
Susceptibility Testing
For specific information regarding susceptibility test interpretive criteria and associated test methods and quality control standards recognized by FDA for daptomycin, please see:
https://www.fda.gov/STIC .
Adult Animals
In animals, daptomycin administration has been associated with effects on skeletal muscle. However, there were no changes in cardiac or smooth muscle. Skeletal muscle effects were characterized by microscopic degenerative/regenerative changes and variable elevations in creatine phosphokinase (CPK). No fibrosis or rhabdomyolysis was evident in repeat-dose studies up to the highest doses tested in rats (150 mg/kg/day) and dogs (100 mg/kg/day). The degree of skeletal myopathy showed no increase when treatment was extended from 1 month to up to 6 months. Severity was dose-dependent. All muscle effects, including microscopic changes, were fully reversible within 30 days following the cessation of dosing.
In adult animals, effects on peripheral nerve (characterized by axonal degeneration and frequently accompanied by significant losses of patellar reflex, gag reflex, and pain perception) were observed at daptomycin doses higher than those associated with skeletal myopathy. Deficits in the dogs' patellar reflexes were seen within 2 weeks after the start of treatment at 40 mg/kg/day (9 times the human Cmax at the 6 mg/kg/day dose), with some clinical improvement noted within 2 weeks after the cessation of dosing. However, at 75 mg/kg/day for 1 month, 7 of 8 dogs failed to regain full patellar reflex responses within a 3-month recovery period. In a separate study in dogs receiving doses of 75 and 100 mg/kg/day for 2 weeks, minimal residual histological changes were noted at 6 months after the cessation of dosing. However, recovery of peripheral nerve function was evident.
Tissue distribution studies in rats showed that daptomycin is retained in the kidney but appears to penetrate the blood-brain barrier only minimally following single and multiple doses.
Juvenile Animals
Target organs of daptomycin-related effects in 7-week-old juvenile dogs were skeletal muscle and nerve, the same target organs as in adult dogs. In juvenile dogs, nerve effects were noted at lower daptomycin blood concentrations than in adult dogs following 28 days of dosing. In contrast to adult dogs, juvenile dogs also showed evidence of effects in nerves of the spinal cord as well as peripheral nerves after 28 days of dosing. No nerve effects were noted in juvenile dogs following 14 days of dosing at doses up to 75 mg/kg/day.
Administration of daptomycin to 7-week-old juvenile dogs for 28 days at doses of 50 mg/kg/day produced minimal degenerative effects on the peripheral nerve and spinal cord in several animals, with no corresponding clinical signs. A dose of 150 mg/kg/day for 28 days produced minimal degeneration in the peripheral nerve and spinal cord as well as minimal to mild degeneration of the skeletal muscle in a majority of animals, accompanied by slight to severe muscle weakness evident in most dogs. Following a 28-day recovery phase, microscopic examination revealed recovery of the skeletal muscle and the ulnar nerve effects, but nerve degeneration in the sciatic nerve and spinal cord was still observed in all 150 mg/kg/day dogs.
Following once-daily administration of daptomycin to juvenile dogs for 28 days, microscopic effects in nerve tissue were noted at a Cmax value of 417 mcg/mL, which is approximately 3-fold less than the Cmax value associated with nerve effects in adult dogs treated once daily with daptomycin for 28 days (1308 mcg/mL).
Neonatal Animals
Neonatal dogs (4 to 31 days old) were more sensitive to daptomycin-related adverse nervous system and/or muscular system effects than either juvenile or adult dogs. In neonatal dogs, adverse nervous system and/or muscular system effects were associated with a Cmax value approximately 3-fold less than the Cmax in juvenile dogs, and 9-fold less than the Cmax in adult dogs following 28 days of dosing. At a dose of 25 mg/kg/day with associated Cmax and AUCinf values of 147 mcg/mL and 717 mcg∙h/mL, respectively (1.6 and 1.0-fold the adult human Cmax and AUC, respectively, at the 6 mg/kg/day dose), mild clinical signs of twitching and one incidence of muscle rigidity were observed with no corresponding effect on body weight. These effects were found to be reversible within 28 days after treatment had stopped.
At higher dose levels of 50 and 75 mg/kg/day with associated Cmax and AUCinf values of ≥321 mcg/mL and ≥1470 mcg∙h/mL, respectively, marked clinical signs of twitching, muscle rigidity in the limbs, and impaired use of limbs were observed. Resulting decreases in body weights and overall body condition at doses ≥50 mg/kg/day necessitated early discontinuation by postnatal day (PND) 19.
Histopathological assessment did not reveal any daptomycin-related changes in the peripheral and central nervous system tissue, as well as in the skeletal muscle or other tissues assessed, at any dose level.
No adverse effects were observed in the dogs that received daptomycin at 10 mg/kg/day, the NOAEL, with associated Cmax and AUCinf values of 62 mcg/mL and 247 mcg∙h/mL, respectively (or 0.6 and 0.4-fold the adult human Cmax and AUC, respectively at the 6 mg/kg dose).
Adults with cSSSI
Adult patients with clinically documented complicated skin and skin structure infections (cSSSI) (Table 15) were enrolled in two randomized, multinational, multicenter, investigator-blinded trials comparing daptomycin for injection (4 mg/kg IV every 24h) with either vancomycin (1 g IV q12h) or an anti-staphylococcal semi-synthetic penicillin (i.e., nafcillin, oxacillin, cloxacillin, or flucloxacillin; 4 to 12 g IV per day). Patients could switch to oral therapy after a minimum of 4 days of IV treatment if clinical improvement was demonstrated. Patients known to have bacteremia at baseline were excluded. Patients with creatinine clearance (CLCR) between 30 and 70 mL/min were to receive a lower dose of daptomycin for injection as specified in the protocol; however, the majority of patients in this subpopulation did not have the dose of daptomycin for injection adjusted.
Table 15: Investigator's Primary Diagnosis in the cSSSI Trials in Adult Patients (Population: ITT)| Primary Diagnosis | Adult Patients (Daptomycin for injection/ ComparatorComparator: vancomycin (1 g IV q12h) or an anti-staphylococcal semi-synthetic penicillin (i.e., nafcillin, oxacillin, cloxacillin, or flucloxacillin; 4 to 12 g/day IV in divided doses). ) |
|---|
Study 9801 N=264 / N=266 | Study 9901 N=270 / N=292 | Pooled N=534 / N=558 |
|---|
| Wound Infection | 99 (38%) / 116 (44%) | 102 (38%) / 108 (37%) | 201 (38%) / 224 (40%) |
| Major Abscess | 55 (21%) / 43 (16%) | 59 (22%) / 65 (22%) | 114 (21%) / 108 (19%) |
| Ulcer Infection | 71 (27%) / 75 (28%) | 53 (20%) / 68 (23%) | 124 (23%) / 143 (26%) |
| Other Infection The majority of cases were subsequently categorized as complicated cellulitis, major abscesses, or traumatic wound infections. | 39 (15%) / 32 (12%) | 56 (21%) / 51 (18%) | 95 (18%) / 83 (15%) |
One trial was conducted primarily in the United States and South Africa (study 9801), and the second was conducted at non-US sites only (study 9901). The two trials were similar in design but differed in patient characteristics, including history of diabetes and peripheral vascular disease. There were a total of 534 adult patients treated with daptomycin for injection and 558 treated with comparator in the two trials. The majority (89.7%) of patients received IV medication exclusively.
The efficacy endpoints in both trials were the clinical success rates in the intent-to-treat (ITT) population and in the clinically evaluable (CE) population. In study 9801, clinical success rates in the ITT population were 62.5% (165/264) in patients treated with daptomycin for injection and 60.9% (162/266) in patients treated with comparator drugs. Clinical success rates in the CE population were 76.0% (158/208) in patients treated with daptomycin for injection and 76.7% (158/206) in patients treated with comparator drugs. In study 9901, clinical success rates in the ITT population were 80.4% (217/270) in patients treated with daptomycin for injection and 80.5% (235/292) in patients treated with comparator drugs. Clinical success rates in the CE population were 89.9% (214/238) in patients treated with daptomycin for injection and 90.4% (226/250) in patients treated with comparator drugs.
The success rates by pathogen for microbiologically evaluable patients are presented in Table 16.
Table 16: Clinical Success Rates by Infecting Pathogen in the cSSSI Trials in Adult Patients (Population: Microbiologically Evaluable)| Pathogen | Success Rate n/N (%) |
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| Daptomycin for injection | Comparator Comparator: vancomycin (1 g IV q12h) or an anti-staphylococcal semi-synthetic penicillin (i.e., nafcillin, oxacillin, cloxacillin, or flucloxacillin; 4 to 12 g/day IV in divided doses). |
|---|
| Methicillin-susceptible Staphylococcus aureus (MSSA) As determined by the central laboratory. | 170/198 (86%) | 180/207 (87%) |
| Methicillin-resistant Staphylococcus aureus (MRSA) | 21/28 (75%) | 25/36 (69%) |
| Streptococcus pyogenes | 79/84 (94%) | 80/88 (91%) |
| Streptococcus agalactiae | 23/27 (85%) | 22/29 (76%) |
| Streptococcus dysgalactiae subsp. equisimilis | 8/8 (100%) | 9/11 (82%) |
| Enterococcus faecalis (vancomycin-susceptible only) | 27/37 (73%) | 40/53 (76%) |
Pediatric Patients (1 to 17 Years of Age) with cSSSI
The cSSSI pediatric trial was a single prospective multi-center, randomized, comparative trial. A total of 396 pediatric patients aged 1 to 17 years with cSSSI caused by Gram positive pathogens were enrolled into the study. Patients known to have bacteremia, osteomyelitis, endocarditis, and pneumonia at baseline were excluded. Patients were enrolled in a stepwise approach into four age groups and given age-dependent doses of daptomycin for injection once daily for up to 14 days. The different age groups and doses evaluated were as follows: Adolescents (12 to 17 years) treated with 5 mg/kg of daptomycin for injection (n=113), Children (7 to 11 years) treated with 7 mg/kg of daptomycin for injection (n=113), Children (2 to 6 years) treated with 9 mg/kg of daptomycin for injection (n=125) and Infants (1 to <2 years) treated with 10 mg/kg (n= 45).
Patients were randomized 2:1 to receive daptomycin for injection or a standard of care (SOC) comparator, which included intravenous therapy with either vancomycin, clindamycin, or an anti-staphylococcal semi-synthetic penicillin (nafcillin, oxacillin, or cloxacillin). Patients could switch to oral therapy after clinical improvement was demonstrated (no minimum IV dosing was required).
The primary objective of this study was to evaluate the safety of daptomycin for injection. The clinical outcome was determined by resolution or improvement of symptoms at the End-of-Treatment (EOT), 3 days after the last dose, and Test-of-Cure (TOC), 7-14 days after the last dose. Investigator observed outcomes were verified in a blinded fashion. Of the 396 subjects randomized in the study, 389 subjects were treated with daptomycin for injection or comparator and included in the ITT population. Of these, 257 subjects were randomized to the daptomycin for injection group and 132 subjects were randomized to the comparator group. Approximately 95% of subjects switched to oral therapy. The mean day of switch was day 4, and ranged from day 1 to day 14. The clinical success rates determined at 7–14 days after last dose of therapy (IV and oral) (TOC visit) were 88% (227/257) for daptomycin for injection and 86% (114/132) for comparator.