Abdominal pain resulting from chronic pancreatitis (CP) is often recurrent, intense and long-lasting, and is extremely difficult to treat. Medical analgesic therapy is considered as first choice in pain management of CP, resulting in regularly prescription of opioids. The adverse consequences of prolonged opioid use, including addiction, tolerance and opioid induced hyperalgesia, call for an alternative medical treatment. Cannabis has been used to treat pain for many centuries. Delta-9-tetrahydrocannabinol (Δ9-THC), the psychoactive substance of the cannabis plant, has been shown in previous studies to be a promising analgesic. The development of Namisol®, a tablet containing purified Δ9-THC showing an improved pharmacokinetic profile, provides the opportunity to test the analgesic potential of Δ9-THC in favourable conditions. The current study aims to investigate the analgesic efficacy of Namisol® as add-on analgesic during a long-term treatment (52 days) of abdominal pain resulting from CP.

Inclusion Criteria:

• Aged 18 years or older
• Confirmed chronic pancreatitis
• Pain duration exceeding 3 months, and average NRS≥3
• Stable doses intake of analgesics for the past 2 months
• The patient has been informed about the study, understood the information and signed the informed consent form

Exclusion Criteria:

• Patient took cannabinoids on a regular basis for at least one year
• Patient does not feel a pinprick test in the lower extremities
• Patient has a body mass index (BMI) above 32,0 kg/m2
• Patient suffers from serious painful conditions other than chronic pancreatitis
• Patient has a significant medical disorder that may interfere with the study or may pose a risk for the patient
• Patient uses any kind of concomitant medication that may interfere with the study or may pose a risk for the patient
• Patient does not tolerate oral intake of medication or liquids, or is refrained from oral intake because of medical reasons
• Patient demonstrates clinical relevant deviations in the electrocardiogram (ECG)
• Patient has an actual moderate to severe renal impairment
• Patient has an actual moderate to severe hepatic impairment
• Patient has a presence or history of major psychiatric illness
• Patient has experienced an epileptic seizure in the past
• Patient demonstrates clinically significant laboratory abnormalities
• Patient demonstrates a positive urine drug screen for THC, cocaine, MDMA, and amphetamines
• Patient demonstrates a positive test result on hepatitis B surface antigen, hepatitis C antibody or HIV antibody test
• Patient has a history of sensitivity / idiosyncrasy to THC
• Patient has a known or suspected lactose intolerance
• Female patient is pregnant or breastfeeding
• Patient intends to conceive a child during the course of the study
• Patient participates in another investigational drug study
• Patient has a clinical significant exacerbation in illness
• Patient is unwilling or unable to comply with the lifestyle guidelines