Clinical Pharmacology1

Pharmacodynamics

Similar to other β-lactam antibacterial drugs, the percentage of time of a dosing interval that unbound plasma concentration of meropenem exceeds the meropenem-vaborbactam minimum inhibitory concentration (MIC) against the infecting organism has been shown to best correlate with efficacy in animal and in vitro models of infection. The ratio of the 24-hour unbound plasma vaborbactam AUC to meropenem-vaborbactam MIC is the index that best predicts efficacy of vaborbactam in combination with meropenem in animal and in vitro models of infection.

Pharmacokinetics

Pharmacokinetic (PK) Parameters


The mean PK parameters of meropenem and vaborbactam in healthy adults with normal renal function after single and multiple 3-hour infusions of VABOMERE 4 grams (meropenem 2 grams and vaborbactam 2 grams) administered every 8 hours are summarized in Table 4.

The PK parameters of meropenem and vaborbactam were similar for single and multiple dose administration of VABOMERE™ (meropenem and vaborbactam).

Table 4: Pharmacokinetic Parameters (Mean [SD]) of Meropenem and Vaborbactam Following Administration of VABOMERE 4 grams (meropenem 2 grams and vaborbactam 2 grams) by 3-hour Infusion in Healthy Adult Subjects

Parameter Meropenem Vaborbactam
Single VABOMERE 4-grama Dose (N=8) Multiple VABOMERE
4-grama Doses Administered Every 8 hours for 7 Days (N=8)
Single VABOMERE 4-grama Dose (N=8) Multiple VABOMERE
4-grama Doses Administered Every 8 hours for 7 Days (N=8)
Cmax(mg/L) 46.0 (5.7) 43.4 (8.8) 50.7 (8.4) 55.6 (11.0)
CL (L/h) 14.6 (2.7) 15.1 (2.8) 12.3 (2.2) 10.9 (1.8)
AUC (mg•h/L)b 142.0 (28.0) 138.0 (27.7) 168.0 (32.2) 196.0 (36.7)
T1/2 (h) 1.50 (1.0) 1.22 (0.3) 1.99 (0.8) 1.68 (0.4)

Cmax = maximum observed concentration; CL = plasma clearance; AUC = area under the concentration time curve; T½ = half-life.

aMeropenem 2 grams and vaborbactam 2 grams administered as a 3-hour infusion.

bAUC0-inf reported for single-dose administration; AUC0-8 reported for multiple-dose administration; AUC0-24 is 414 mg•h/L for meropenem and 588 mg•h/L for vaborbactam.


The maximum plasma concentration (Cmax) and area under the plasma drug concentration time curve (AUC) of meropenem and vaborbactam proportionally increased with dose across the dose range studied (1 gram to 2 grams for meropenem and 0.25 grams to
2 grams for vaborbactam) when administered as a single 3-hour intravenous infusion. There is no accumulation of meropenem or vaborbactam following multiple intravenous infusions administered every 8 hours for 7 days in subjects with normal renal function.


The mean population PK parameters of meropenem and vaborbactam in 295 patients (including 35 patients with reduced renal function) after 3-hour infusions of VABOMERE
4 grams (meropenem 2 grams and vaborbactam 2 grams) administered every 8 hours (or dose adjusted based on renal function) are summarized in Table 5.

Table 5: Population Pharmacokinetic Parameters (Mean [SD]) of Meropenem and Vaborbactam Following Administration of VABOMERE 4 grams (meropenem 2 grams and vaborbactam 2 grams) by 3-hour Infusion in Patientsa

Parameter Meropenem Vaborbactam
Cmax (mg/L) 57.3 (23.0) 71.3 (28.6)
AUC0-24, Day 1 (mg•h/L) 637 (295) 821 (369)
AUC0-24, steady-state(mg•h/L) 650 (364) 835 (508)
CL (L/h) 10.5 (6.4) 7.95 (4.3)
T1/2 (h) 2.30 (2.5) 2.25 (2.1)

aMeropenem 2 grams and vaborbactam 2 grams administered as a 3-hour infusion.

Distribution


The plasma protein binding of meropenem is approximately 2%. The plasma protein binding of vaborbactam is approximately 33%.


The steady-state volumes of distribution of meropenem and vaborbactam in patients were 20.2 L and 18.6 L, respectively.

Elimination


The clearance of meropenem in healthy subjects following multiple doses is 15.1 L/h and for vaborbactam is 10.9 L/h. The t1/2 is 1.22 hours and 1.68 hours for meropenem and vaborbactam, respectively.


Metabolism

A minor pathway of meropenem elimination is hydrolysis of the β-lactam ring (meropenem open lactam), which accounts for 22% of a dose eliminated via the urine.

Vaborbactam does not undergo metabolism.


Excretion

Both meropenem and vaborbactam are primarily excreted via the kidneys.

Approximately 40%-60% of a meropenem dose is excreted unchanged within 24-48 hours with a further 22% recovered as the microbiologically inactive hydrolysis product. The mean renal clearance for meropenem was 7.8 L/h. The mean non-renal clearance for meropenem was 7.3 L/h which comprises both fecal elimination (~2% of dose) and degradation due to hydrolysis.

For vaborbactam, 75%-95% of the dose was excreted unchanged in the urine over a 24 to 48-hour period. The mean renal clearance for vaborbactam was 8.9 L/h. The mean non-renal clearance for vaborbactam was 2.0 L/h indicating nearly complete elimination of vaborbactam by the renal route.

Specific Populations


Patients With Renal Impairment

Following a single dose of VABOMERE, pharmacokinetic studies with meropenem and vaborbactam in subjects with renal impairment have shown that meropenem AUC0-inf ratios to subjects with normal renal function are 1.28, 2.07, and 4.63 for subjects with mild (eGFR of 60 to 89 mL/min/1.73m2), moderate (eGFR of 30 to 59 mL/min/1.73m2), and severe (eGFR <30 mL/min/1.73m2) renal impairment, respectively; vaborbactam AUC0-inf ratios to subjects with normal renal function are 1.18, 2.31, and 7.8 for subjects with mild, moderate, and severe renal impairment, respectively [see Dosing and Administration]. Hemodialysis removed 38% of the meropenem dose and 53% of the vaborbactam dose. Vaborbactam exposure was high in subjects with ESRD (eGFR <15 ml/min/1.73m2). Vaborbactam exposure was higher when VABOMERE was administered after hemodialysis (AUC0-inf ratio to subjects with normal renal function of 37.5) than when VABOMERE was administered before hemodialysis (AUC0-inf ratio to subjects with normal renal function of 10.2).

Patients With Hepatic Impairment

A pharmacokinetic study conducted with an intravenous formulation of meropenem in patients with hepatic impairment has shown no effects of liver disease on the pharmacokinetics of meropenem.

Vaborbactam does not undergo hepatic metabolism. Therefore, the systemic clearance of meropenem and vaborbactam is not expected to be affected by hepatic impairment.

Geriatric Patients

In elderly patients with renal impairment, plasma clearances of meropenem and vaborbactam were reduced, correlating with age-associated reduction in renal function.

Male and Female Patients

Meropenem and vaborbactam Cmax and AUC were similar between males and females using a population pharmacokinetic analysis.

Racial or Ethnic Groups

No significant difference in mean meropenem or vaborbactam clearance was observed across race groups using a population pharmacokinetic analysis.

Drug Interactions


No drug-drug interaction was observed between meropenem and vaborbactam in clinical studies with healthy subjects.


Based upon the in vitro and in vivo data available to date, there is a low potential for clinically significant drug interactions with vaborbactam.

Vaborbactam at clinically relevant concentrations does not inhibit the cytochrome P450 isoforms CYP1A2, CYP2B6, CYP2C8, CYP2C9, CYP2C19, CYP2D6, and CYP3A4 in vitro human liver microsomes. Vaborbactam showed no potential for in vitro induction of CYP1A2, CYP2B6, and CYP3A4 in human hepatocytes. Studies evaluating the potential for meropenem to interact with CYP450 enzymes or active transport systems have not been conducted. However, carbapenems as a class have not shown the potential for inhibition or induction CYP450 enzymes and clinical experience suggests that such effects are unlikely.

Vaborbactam does not inhibit the following hepatic and renal transporters in vitro at clinically relevant concentrations: P-gp, BCRP, OAT1, OAT3, OCT1, OCT2, OATP1B1, OATP1B3 or BSEP. Vaborbactam was not a substrate of OAT1, OAT3, OCT2, P-gp, and BCRP.

Meropenem is a substrate of OAT1 and OAT3 and as such, probenecid competes with meropenem for active tubular secretion and thus inhibits the renal excretion of meropenem. Following administration of probenecid with meropenem, the mean systemic exposure increased 56% and the mean elimination half-life increased 38%.

Concomitant administration of meropenem and valproic acid has been associated with reductions in valproic acid concentrations with subsequent loss in seizure control.

VABOMERE MOA

VABOMERE MOA

Review the Mechanism of Action

DOSING VABOMERE

DOSING VABOMERE

Get details about VABOMERE dosing

Reference: 1. Vabomere [package insert]. Lincolnshire, IL: Melinta Therapeutics, Inc.; 2018.

INDICATIONS AND USAGE

VABOMERE™ (meropenem and vaborbactam) is indicated for the treatment of patients 18 years of age and older with complicated urinary tract infections (cUTI) including pyelonephritis caused by the following susceptible microorganisms: Escherichia coli, Klebsiella pneumoniae, and Enterobacter cloacae species complex.

To reduce the development of drug-resistant bacteria and maintain the effectiveness of VABOMERE and other antibacterial drugs, VABOMERE should be used only to treat or prevent infections that are proven or strongly suspected to be caused by susceptible bacteria.


IMPORTANT SAFETY INFORMATION

Contraindications

VABOMERE is contraindicated in patients with known hypersensitivity to any components of VABOMERE (meropenem and vaborbactam), or to other drugs in the same class or in patients who have demonstrated anaphylactic reactions to beta-lactam antibacterial drugs.

Warnings and Precautions

  • Hypersensitivity reactions were reported in patients treated with VABOMERE in the clinical trials. Serious and occasionally fatal hypersensitivity (anaphylactic) reactions and serious skin reactions have been reported in patients receiving therapy with beta-lactam antibacterial drugs. There have been reports of individuals with a history of penicillin hypersensitivity who have experienced severe hypersensitivity reactions when treated with another beta-lactam antibacterial drug. If an allergic reaction to VABOMERE occurs, discontinue the drug immediately.
  • Seizures and other adverse Central Nervous System (CNS) experiences have been reported during treatment with meropenem, which is a component of VABOMERE. Close adherence to the recommended dosage regimens is urged, especially in patients with known factors that predispose to convulsive activity.
  • Clostridium difficile-associated diarrhea (CDAD) has been reported with use of nearly all antibacterial agents, including VABOMERE, and may range in severity from mild diarrhea to fatal colitis. 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 antibacterial drug use not directed against C. difficile may need to be discontinued.
  • The concomitant use of VABOMERE and valproic acid or divalproex sodium is generally not recommended. Case reports in the literature have shown that co-administration of carbapenems, including meropenem, to patients receiving valproic acid or divalproex sodium results in a reduction in valproic acid concentrations. The valproic acid concentrations may drop below the therapeutic range as a result of this interaction, therefore increasing the risk of breakthrough seizures. If administration of VABOMERE is necessary, consider supplemental anticonvulsant therapy.
  • In patients with renal impairment, thrombocytopenia has been observed in patients treated with meropenem, but no clinical bleeding has been reported.
  • Alert patients receiving VABOMERE on an outpatient basis regarding adverse reactions such as seizures, delirium, headaches and/or paresthesias that could interfere with mental alertness and/or cause motor impairment.
  • Prescribing VABOMERE in the absence of a proven or strongly suspected bacterial infection is unlikely to provide benefit to the patient and increases the risk of drug-resistant bacteria.
  • As with other antibacterial drugs, prolonged use of VABOMERE may result in overgrowth of nonsusceptible organisms.

Adverse Reactions

The most frequently reported adverse reactions occurring in ≥3% of patients treated with VABOMERE were headache, phlebitis/infusion site reactions, and diarrhea.

Please see Full Prescribing Information.