Switzerland's cannabis pilot trials: the only European experiment with a control group

A research carve-out, not a legalisation

Switzerland has not legalised cannabis. It has written a research exemption into its Narcotics Act and then used it seriously. Article 8a permits pilot trials of regulated cannabis supply, and the Federal Office of Public Health authorises them one by one against published criteria.

The distinction matters because the trials are frequently described abroad as Swiss legalisation. Outside an authorised trial, non-medical cannabis above 1 percent THC remains prohibited. Participation is what confers legal purchase, not residence.

The constraints written into the statute

• Trials must be geographically limited to one or more communes.
• Duration is limited to five years, with one possible extension of no more than two years where justified.
• Participant numbers must be the minimum needed for meaningful scientific conclusions, and may not exceed 5,000 per trial.
• Trials may be run by public or private organisations, and must submit a full study protocol covering methodology, participant information, funding and timeframe.
• The enabling legislation itself applies for ten years, from 15 May 2021 to 14 May 2031.

Why the variety of models is the point

The FOPH has authorised eight trials since the first began dispensing in 2023, and they do not test the same thing. Some operate as commercial market models with product sold for profit through pharmacies or specialist shops; others use non-profit, state monopoly or mixed structures. Roughly half are constructed as randomised controlled trials with a group that receives nothing.

The most recently authorised trial adds a variable no earlier Swiss pilot tested: home delivery, compared against pharmacy collection and a control group. That is a policy question dressed as a logistics question, and no other European jurisdiction is set up to answer it with data.

The 2031 problem

Because the enabling framework expires in May 2031 and individual trials run up to five years with a possible two-year extension, Switzerland has effectively built itself a deadline. Trials authorised late in the window cannot complete a full course before the legal basis lapses, which means the political decision about what follows has to be taken while some evidence is still incomplete.

Medical cannabis, separately, has been prescribable without a federal exemption since August 2022, with Swissmedic licensing the supply chain upstream. Reimbursement, not authorisation, is the constraint patients now report.

LeafCurrent tracks FOPH authorisations and published interim reports. Enrolment and sales figures circulating in trade press are snapshots at specific cut-off dates and should be read as a moving baseline rather than a market size.