A Pilot Study of Ciprofloxacin Plus Gemcitabine and Nab-Paclitaxel Chemotherapy in Patients With Metastatic Pancreatic Ductal Adenocarcinoma.

Oral ciprofloxacin (study drug) will be administered twice a day throughout each 28-day cycle of gemcitabine and nab-paclitaxel chemotherapy. The patient will start taking ciprofloxacin from the evening of day 1 of chemotherapy and end on the morning of day 29 of each cycle.

Ciprofloxacin tablets should be taken in the morning and evening at about the same time each day. Swallow the tablet whole. Do not split, crush or chew the tablet. Ciprofloxacin can be taken with or without food

With each study visit, the physician will prescribe 1-month supply of oral ciprofloxacin to be taken home and self-administered by the patient. The physician will have to indicate "pancreatic cancer microbiome study" on the remarks column for each cycle oral ciprofloxacin is ordered.

Inclusion criteria

• Signed informed consent. Written informed consent must be obtained prior to performing any study-related procedures.
• Age ≥ 21 years
• Histologically or cytologically confirmed, treatment-naïve, locally advanced or metastatic pancreatic adenocarcinoma planned to commence on gemcitabine and nab-paclitaxel chemotherapy.
• Patient must have measurable disease as defined by the Response Evaluation Criteria in Solid Tumors Version 1.1 (RECIST v 1.1 guidelines)
• Life expectancy >3 months
• Eastern Cooperative Oncology Group (ECOG) performance status of 0-2
• CrCl ≥ 30 ml/min

Exclusion criteria

• Known hypersensitivity or allergy to ciprofloxacin or other quinolones
• On tizanidine or theophylline and unable to stop these medication
• Known QTc prolongation (QTc >500 msec) or torsade de pointes
• Presence of Clostridium difficile-associated diarrhea or colitis
• Known history of myasthenia gravis
• Known G6PD deficiency