Absorption of sublingually delivered fentanyl (Abstral®) in head and neck cancer patients treated with curatively aimed chemo-radiotherapy

SUMMARY



Rationale: The majority of head and neck cancer patients treated with curatively aimed chemoradiotherapy suffer from severe mucositis. Mucositis can cause different problems e.g. pain and difficulties with swallowing. Furthermore, xerostomia often occurs after chemoradiotherapy, due to destruction of the salivary glands. From the third week of radiotherapy, oral pain is getting worse, and will require analgesics. Mucositis is increasing in the weeks following and worst at the end of the radiotherapy treatment. Most patients need strong opioids for the treatment of the pain caused by mucositis. Fentanyl is a widely used strong opioïd and is highly lipophilic. Nowadays there are several immediate release fentanyl products for the treatment of breakthrough pain. One of them is sublingually delivered fentanyl, (Abstral ®). Abstral is placed directly under the tongue to be absorbed by the mucosa. It is unknown if mucositis and xerostomia will influence the absorption of sublingual fentanyl and thereby its potential efficacy in case of breakthrough pain.



Objective: First objective: To study the influence of mucositis on the absorption of sublingually delivered fentanyl (Abstral ®) in head and neck cancer patients treated with chemoradiotherapy. Secondary objectives: to study the influence of xerostomia on the absorption of sublingually delivered fentanyl (Abstral®) in these patients 6 weeks after treatment with chemoradiotherapy; to study the relation between the dose of radiotherapy administered sublingually and the changes in pharmacokinetics of sublingually delivered fentanyl (Abstral®); and to study the effect of sublingually delivered fentanyl (Abstral®) on pain intensity in these patients before, during and after chemoradiotherapy.

First objective: To study the influence of mucositis on the absorption of sublingually delivered fentanyl (Abstral ®) in head and neck cancer patients treated with chemoradiotherapy. Secondary objectives: to study the influence of xerostomia on the absorption of sublingually delivered fentanyl (Abstral®) in these patients 6 weeks after treatment with chemoradiotherapy; to study the relation between the dose of radiotherapy administered sublingually and the changes in pharmacokinetics of sublingually delivered fentanyl (Abstral®); and to study the effect of sublingually delivered fentanyl (Abstral®) on pain intensity in these patients before, during and after chemoradiotherapy.

4 different time points: 24-72 hrs before the start of the chemoradiotherapy (T=0), 24-72 hrs before the planned start of the 2nd gift of chemotherapy (T=1) , 24-72 hrs before the planned start of the 3rd gift of chemotherapy (T=2) and six weeks after the end of the chemoradiotherapy (T=last).

Patients will be given a single dose of Abstral® 200 mcg sublingually. Pharmacokinetics of sublingually delivered fentanyl will be measured at 4 different time points: 24-72 hrs before the start of the chemoradiotherapy (T=0), 24-72 hrs before the planned start of the 2nd gift of chemotherapy (T=1) , 24-72 hrs before the planned start of the 3rd gift of chemotherapy (T=2) and six weeks after the end of the chemoradiotherapy (T=last).