Dr. Lorraine Nolan:

I will respond to a couple of points. Deputy Kelleher spoke of the mindset towards cannabis, which comes from its history and the fact that it has always been viewed by regulators as a substance of abuse. There are, however, authorised medicines which contain cannabis such as Sativex and a range of synthetic cannabinoid products. This shows the flexibilities among regulators who recognise that they have therapeutic value and that, once there is sufficient scientific evidence, a product can be authorised as a medicine and viewed as part of conventional therapy. Dr. Doherty said the issue was one of evidence and it is a lack of evidence, rather than division, which is the underlying factor. We echo that and while we recognise that there is emerging evidence from research on a range of cannabis-type products many reviews, such as the Barnes report and the Cochrane reviews, cite the limitations within that emerging evidence. The Barnes report, which is cautious and balanced, puts forward strong evidence in favour of the use of cannabis for neuropathic pain, spasms associated with multiple sclerosis and nausea control but found that, in other cases, the evidence was moderate or poor. It also cites limitations in the studies which have been conducted in that they involved small numbers of patients, were not peer reviewed and included controlled populations. We are getting there but we are not there yet in terms of having the evidence to authorise them as medicines.

Other jurisdictions have introduced frameworks to allow access to cannabis for medicinal purposes, but all of these have been demand led and are part of drugs legislation in those countries. Access has been allowed by a relaxation of drug laws so they sit outside what is considered conventional medicine. The focus is on ensuring a controlled supply source that is regulated, particularly in the case of cannabis material, the purity and content of whose cannabinoid components can be controlled. In this way the chemical content, such as the amount of THC and CBD, is known and standardised. The focus has not been on a level of quality control which one would accept from a conventional medicine, though elements of quality control have been put into the system to give reassurance on the quality of the dried cannabis.

Deputy Smith said that side effects were associated with conventional medicines, such as those used to treat epilepsy, and that is a fact but an authorised medicine has been through a rigorous scientific evaluation. All medicines carry risks and all medicines can have side effects. Our job in assessing medicines is to monitor those risks, weigh them against the benefits and ensure the profile is positive in favour of the benefit. The side effects of an authorised medicine are identified during its development. The risks are known and medicines are sold in the market with patient information leaflets showing a product's characteristics. They always list the side effects and say what the expected risks are. Once a medicine is authorised it is subject to a rigorous process whereby the experience of patients is monitored, and things which may not have been anticipated are reported to competent authorities, properly investigated and addressed by regulators. It may be that extra controls are applied or the supply restricted when they are not suitable for full populations. A rigorous system is in place for conventional medicines and they have a full benefit-risk assessment. The risks associated with their use are known and anticipated. We equip our health care professionals to monitor them and, where side effects or new signals arise, they can be reported to an authority and be appropriately investigated.

A point was made about the importance of the best interests of patients and nobody in this room would disagree that the best treatment option for a patient is an authorised medicine. In the absence of the availability of an authorised medicine, or one authorised in another jurisdiction and on which an assessment has been carried out by a regulatory authority, the next best option is access through a clinical trial. There is an appropriate level of regulatory oversight of these mechanisms but there is a limit to the number of cannabis products which are available to meet these needs. They are investigational products although some, as Dr. Doherty pointed out in the case of Epidiolex, are more advanced and there is more evidence with which to work.

In its review of this area the Health Products Regulatory Authority, HPRA, will weigh up all these factors. It will take into account emerging evidence in a balanced and impartial way which takes into account the risks associated with using cannabis, which is typically used as an adjunct supportive treatment in an established ongoing therapeutic programme for a patient. The review will assess how it can be used and what harms are associated with cannabis. The information we have on the harms comes from illicit use and there are strong links between prolonged and excessive use of cannabis and psychosis and schizophrenia. These things are more prevalent in those who start to use cannabis illicitly at an early age and in people with a susceptibility to mental illness. There have been very limited studies which have monitored the side effects of the medicinal use of cannabis. A meta-analysis by the American Medical Association looked at 80 studies and found side effects or adverse events in 69 of them, though they were not hugely significant, being mainly headaches, nausea and drowsiness.

To assist us in our review we will convene a working group of experts as it is important that we bring on board the clinicians practising in the area. We have already identified a number who have agreed to participate and we would like to involve patients in order that we can bring together all the information and review it in an impartial way to see if it has a benefit and a place in patient treatment. In other jurisdictions which have relaxed drug laws and frameworks, there has always been a detailed upfront review and the Barnes report, of which I spoke earlier, was part of the initiatives taken in the UK to advance this issue.