IACM-Bulletin of September 16, 2001

Science UK — 77 percent show relief in pain studies of GW

GW Pharmaceuticals said on 10 September its cannabis spray had delivered significant benefit for 77 percent of chronic pain sufferers in clinical trials. 41 out of the first 53 patients enrolled in the Phase I and II studies derived statistically significant benefit, including reduced pain, improved sleep and overall symptom relief.

Side effects, including headaches and nausea, were "predictable and generally well tolerated," the study added. Some patients did become intoxicated but generally the ability to control dosage with the spray mechanism allowed users to strike a balance between pain reduction and psychic effects.

Results of trials at three centres in Great Britain (Oxford, Great Yarmouth and London) were presented at the meeting of the American Academy of Pain Management in Arlington.

Dr William Notcutt of James Paget Hospital in Great Yarmouth in eastern England outlined promising results from one of the studies at the British Association for the Advancement of Science Conference in Glasgow (Scotland) on 3 September. He studied 23 people with intractable pain for more than a year. Only one of the 23 patients failed to benefit from the cannabis spray that is applied under the tongue and two others dropped out because of side effects.

(Sources: Reuters of 3 and 10 September 2001, Financial Times of 4 September 2001)

Science UK — 200 patients enrolled in multiple sclerosis study of MRC

Two hundred people have signed up for the first large scale British study into the effects of cannabis on multiple sclerosis, it was announced on 6 September.

The research is funded with 1.2 million pounds (about 1.77 million US dollars) by the Medical Research Council (MRC). The study protocol was developed by the Royal Pharmaceutical Society of Great Britain.

Dr John Zajicek of Derriford Hospital, Plymouth, is leading the project. In January 2001 the first recruits were signed up in Plymouth and from June the trial was extended nationwide. In total 660 people are needed for the three-year programme, which will involve 38 hospitals across Britain.

Patients are randomly given one of three treatments, capsules with cannabis extract, THC capsules (Marinol), or placebo capsules. Results are expected by summer 2003.

(Source: PA News of 6 September 2001)

News in brief

Science — Neuroprotection

THC was neuroprotective in rats given the toxic agent ouabain. THC treated animals showed reduced volume of oedema by 22% in the acute phase and 36% less nerve damage after 7 days. The effect was not CB1 receptor mediated. (Source: van der Stelt, et al. J Neurosci 2001 Sep 1;21(17):6475-6479)

Science — Antitumour effects

A synthetic non-psychotropic derivative of the THC metabolite THC-CCOH showed antitumour effects in mice. Ajulemic acid (CT3) inhibited the growth of subcutaneously implanted human glioma cells by acting primarily via CB2 receptors. In vitro, ajulemic acid proved to be approximately one-half as potent as THC in inhibiting tumour growth against a variety of cancer cell lines. However, its effects lasted longer. (Source: Recht LD, et al. Biochem Pharmacol 2001 Sep 15;62(6):755-763)

Science — Discrimination of use

11-COOH-THCV (11-nor-delta-9-tetrahydrocannabivarin-9-carboxylic acid), a major metabolite of delta-9-tetrahydrocannabivarin (THCV), was identified in the urine of cannabis users but not in the urine of users of Marinol (THC). Thus, the identification of 11-COOH-THCV indicates the use or ingestion of natural cannabis products. THCV is one of the 9 known cannabinoids of the THC type. (Source: ElSohly et al. J Anal Toxicol 2001 Sep;25(6):476-480)

Science — Schizotypal features

Research examined the relationship between cannabis use and schizotypal features in 20 healthy cannabis users and 20 controls, all of them students of the university of Hamburg. Cannabis users exceeded controls in schizotypal scores. Schizotypal subjects seem to be more likely to use cannabis than the general population. (Source: Mass R, et al. Psychopathology 2001 Jul;34(4):209-214)