Orexigenic Therapy With Delta-9-tetrahydrocannabinol in Advanced Cancer Patients With Chemosensory Abnormalities - a Pilot Study

Appetite stimulants are the common treatment for cancer-induced anorexia. However, only 30% of advanced cancer patients respond and benefit from appetite stimulants, which may be due in part to sensory abnormalities, as a person who is experiencing food aversion due to taste and smell changes may be unable to respond to these agents. Of the appetite stimulants available for use in clinical practice only Marinol, or THC, has the potential to increase food intake by improving appetite as well as by amplifying the taste of food through the brain's reward pathway.

A 22-day, double blind, randomized, placebo-controlled trial will be conducted. Participants will start at 2.5mg of THC or placebo once daily for the first 3 days and then increase to 2.5mg of THC or placebo twice daily before lunch and supper. Participant's will complete the following survey tools pre and post-treatment: Taste and Smell Survey to assess the severity and change in chemosensory complaint scores; 3-day dietary record to determine the change in caloric intake and shift in food preference by macronutrient analysis; 24-hour urine collections to validate the 3-day dietary record; Satiety Labelled Intensity Magnitude scale for subjective appetite ratings; Food Preference Checklist to assess objective shifts in macronutrient and flavor preferences; Functional Assessment of Anorexia/Cachexia Therapy questionnaire to assess participant's QOL; interview to determine the cause and effects of chemosensory alterations; Edmonton Symptom Assessment Scale to assess nausea; and Side Effect Survey to document the tolerability of the drug (post-treatment only). Participants will complete the survey tools with the aid of the researcher. All tools are short and easy to complete, which minimizes patient burden.

Inclusion criteria

• advanced cancer patients (defined as locally recurrent or metastatic) over 18 years old with a decreased food intake for at least 2 weeks (reported by physician or subject)
• able to complete questionnaires in English
• able to provide informed consent
• life expectancy of greater than 2 months (as determined by physician)
• chemosensory complaint score > 1

Exclusion criteria

• receiving enteral or parenteral feedings
• allergies or sensitivity to THC and/or sesame seed oil
• history of substance abuse or psychotic episodes
• mechanical obstruction of alimentary tract, mouth or nose
• received chemotherapy in the last 2 weeks
• received radiation therapy to the head/neck area
• brain tumor
• nausea score greater than 5 on ESAS
• history of tachyarrhythmias, angina pectoris or hypertension
• current diagnosis of liver impairment
• use of marijuana within 30 days prior to start of trial