What is CUPID?
CUPID stands for Cannabinoid Use in Progressive Inflammatory brain Disease. CUPID is a clinical trial which will evaluate whether THC, one of many chemical compounds (cannabinoids) found in the cannabis plant, might slow the development of disability in multiple sclerosis (MS). The trial began in 2006 and is expected to complete in 2012. Recruitment to this study is now complete, with 493 people with progressive MS from across the UK successfully recruited. CUPID is a publicly funded study.
Why is CUPID taking place?
Current treatments for MS are either designed to target the immune system in the early stages of relapsing-remitting MS (disease-modifying drugs) or else are aimed at helping specific symptoms such as muscle spasms or bladder problems. Few treatments have yet been found to be effective in primary or secondary progressive MS, so there is considerable interest in finding new treatments which may slow down long-term disease progression.
Results from our previous study (CAMS study) showed that THC appeared to have an effect on slowing disability, when taken for a year. In order to find out if THC really does slow progression of disability in MS, we have designed a new study, over a longer period of time. In this study, we will assess the effects of THC on progressive MS, by comparing it with an inactive substance, called a placebo.
What type of study is this?
The CUPID study is a randomised trial which means that each participant's treatment is chosen randomly (by chance) by a computer at the beginning of the trial. Participants are allocated to receive either active cannabis treatment (THC) or a placebo (dummy) treatment. Two thirds of the people in the study are allocated to active treatment and one third to placebo. Both treatments are in the form of capsules, taken by mouth, and all capsules look identical. This is a double blind study which means that neither the participants nor the study doctors know which treatment people are taking until the end of the study, in order that study assessments are not biased.