According to new research, a cannabis-based drug works as a painkiller and may also slow disease progression, in rheumatoid arthritis patients.
The drug, Sativex, produced by GW Pharmaceuticals, has featured in the first ever controlled trial of a cannabis-based medicine (CBM) in rheumatoid arthritis.
The researchers from the Royal National Hospital for Rheumatic Diseases, in Bath, England, say significant pain-relieving effects were observed and disease activity was significantly suppressed following the Sativex treatment.
They say that while the differences are small and variable across the population, they represent benefits of clinical relevance and show the need for more detailed investigation.
Of the 56 patients in the five-week randomized study, 31 were given Sativex daily by fixed delivery oromucosal spray and 27 received placebo.
Each spray of Sativex delivers Tetrahydrocannabinol (2.7mg) and cannabidiol (2.5mg).
Pain was assessed in movement and at rest and morning stiffness and sleep quality was also measured.
The cannabis-based drug was seen to produce statistically significant improvements in pain of movement, pain at rest, quality of sleep, and disease activity.
Philip Robson, Director of Cannaboid Research Institute, Oxford and one of the authors, says though a preliminary study, it is a promising start.
Pain relief was over and above the standard treatment already being taken in a stabilized way.
The large majority of side effects were mild or moderate and the treatment group showed no serious adverse effects or withdrawals due to side effects.
Three patients (11 percent) withdrew from the placebo group after experiencing adverse events such as mild dizziness, light-headedness, and dry mouth.
The study was funded by GW pharmaceuticals, which with Bayer, has launched Sativex for multiple sclerosis patients in Canada but which has so far failed to secure marketing authorization in Europe.
The research is published online in Rheumatology.