The Duodopa suspension is dispensed into cassettes, which are designed to be connected to an ambulatory pump, and their contents delivered via continuous intraduodenal administration. For the clinical trial, Duodopa suspension is filled into 100 ml capacity, PVC bags housed in polycarbonate medication cassettes. The cassettes are supplied by SIMS Deltec, Inc., St. Paul, Minnesota. The CADD-Legacy Duodopa Ambulatory Infusion Pump is used for delivery of the Duodopa suspension, also supplied by SIMS Deltec. This infusion pump is commonly used both at hospitals and in ambulatory care.
In order to obtain long-term access to the small bowel, surgery is needed. The surgical techniques used are easy and well-known methods (e.g., percutaneous endoscopic gastrostomy [PEG] with a duodenal tube or radiologic gastrojejunostomy). No general anesthesia is needed; only local anesthesia is required. After surgery, the infusion system can be used immediately and the patient can be mobilized. All patients feel some, but seldom severe, pain from the wound, usually not for more than two days. The postoperative risk of complications is small as no general anesthesia is used and the incision is minimal. Transient local infection may appear but is uncomplicated. An increased mortality rate after PEG surgery is seen in patients who already are hospitalised due to severe illness at the time of surgery. However, this has not so far been the case when it comes to patients suitable for Duodopa therapy.
The infusion of Duodopa is intended only for daytime use, starting with a bolus dose in the morning so that the steady-state concentration is rapidly reached. The infusion rate is easily programmed and can be adjusted in steps of 0.1 ml/h (= 2 mg/h). If the patient needs a small extra dose during the day, he/she can press a dose button to infuse a preprogrammed bolus adjustable to 0.1 ml (= 2 mg). The patient can also choose the amount of the extra dose from time to time. Such extra doses are often 10 or 20 mg.
