Continuous Infusion Piperacillin-tazobactam for the Treatment of Cystic Fibrosis (PIPE-CF)

Continuous Infusion Piperacillin-Tazobactam for the Treatment of Pulmonary Exacerbations in Patients With Cystic Fibrosis

Cystic fibrosis is an inherited disorder leading to chronic pulmonary inflammation and infection. A majority of people with cystic fibrosis have large quantities of bacteria residing in their lungs. One of the most common and harmful bacteria is called Pseudomonas aeruginosa. Patients with cystic fibrosis require frequent therapy with intravenous (I.V.) antibiotics to treat lung infections thought to be caused by Pseudomonas aeruginosa. One of the antibiotics frequently used to treat this bacteria is piperacillin-tazobactam. Piperacillin-tazobactam is thought to be the most effective when there is a constant level of drug in the body. The standard way to administer piperacillin-tazobactam is to give several grams 4 times each day as a 30 minute infusion. An alternative way to give piperacillin-tazobactam is by a continuous infusion; a continuous infusion will make it more likely that drug will remain at a constant level in the body. The objective of this study is to determine if administering piperacillin-tazobactam as a continuous infusion is more effective at treating people having a pulmonary exacerbation of cystic fibrosis than a standard 30 minute infusion, 4 times a day.

All patients will receive combination therapy to include piperacillin-tazobactam 400 mg/kg/day (based on piperacillin component, actual body weight) not to exceed 16 grams and tobramycin 12 mg/kg/day extended interval dosing (once daily). Patients randomized to the continuous infusion group will receive a one-time loading dose of 100 mg/kg over 30 minutes followed immediately by initiation of the continuous infusion. Other antibiotics with activity against Pseudomonas aeruginosa are not allowed. Patients may receive an antibiotic for treatment of Staphylococcus aureus if deemed appropriate. Other treatments for pulmonary exacerbation of cystic fibrosis will be left up to the control of the treating physician. Patients will receive a total of 14 days of therapy. If deemed appropriate, patients may be discharged to home where they will continue to receive blinded treatment via an infusion pump. Patients will be evaluated after completing their 14 day course of antibiotics (end of therapy).

piperacillin, tazobactam, pseudomonas aeruginosa, cystic fibrosis, pulmonary exacerbation, continuous infusion, beta lactam

Piperacillin-tazobactam administered at a dose of 400 mg/kg/day (maximum of 16 grams), divided in four equal doses, administered over 30 minutes, four times a day

Piperacillin-tazobactam administered at a dose of 400 mg/kg/day (maximum of 16 grams) as a continuous infusion over 24 hours, once daily

FEV1 will be measured upon enrollment (day 0). FEV1 will also be measured at end of therapy (day 14). If FEV1 is available when patient was stable, prior to enrollment, this value will be treated as baseline FEV1. Change in FEV1 will be calculated from baseline (if available) to day 14 and also Day 0 to day 14

Serum piperacillin concentration will be measured as follows: Intermittent infusion arm: prior to dose (trough), 30 minutes (after completion of infusion), and at 4 hours Continuous infusion arm: collected at the same time as in the intermittent infusion arm

Patients will be followed for time of next subsequent pulmonary exacerbation for up to 52 weeks after completion of receiving study drug. Next pulmonary exacerbation is defined as requiring admission to a hospital for receipt of I.V. antibiotics because of a diagnosis of pulmonary exacerbation.

Sputum density of Pseudomonas aeruginosa will be determined at enrollment, day 3, and at end of therapy

Temperature will be taken multiple times daily according to standard of care. If patients present febrile, time until patient is afebrile and remains afebrile for 24 hours will be recorded.

White blood cell (WBC) count will be measured once daily. If patient presents with WBC count greater than 11.0 x 10^3/mL, time until patient has WBC less than 11.0 x 10^3/mL will be recorded.

Failure of treatment will be defined as patient needing I.V. antibiotics beyond the 14 days allowed in this study. The primary medical team (along with a blinded investigator) treating the patient will determine whether patient requires additional therapy.

Inclusion Criteria: Diagnosis of cystic fibrosis 8 years of age or greater Chronic or intermittent infection with Pseudomonas aeruginosa as defined by the Leeds Criteria Pulmonary exacerbation as defined by Fuchs et al. Exclusion Criteria: Admission for greater than 48 hours prior to enrollment Isolation of Burkholderia spp. in a respiratory tract culture in the prior 12 months Current treatment for allergic bronchopulmonary aspergillosis Pregnant or breast feeding History of solid organ transplantation Renal impairment at time of randomization (< 40 mL/min as calculated by the Cockcroft-Gault equation24 ¬for adults or the Schwartz equation45 for those < 18 years of age) or receipt of hemodialysis Allergy to study medication