Clinical studies - step by step

Clinical studies - step by step
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    Health and medical care or clinical research?

    Compare your idea with previous research

    Search for knowledge among systematic analyses

    Search for gaps in scientific knowledge

    Use data found in registers

    Formulate the problem

    Särskilda regler för läkemedel och medicinteknik

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    Research plan

    Statistical analysis plan

    Information to study participants

    Insurance for study participants

    Study budget

    Registering your study

    Handling of personal data

    Health economics evaluation

    Specific rules for clinical trials with medicines or medical devices

    Särskilda regler för läkemedel och medicinteknik

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    Applying for an ethical review

    Applying for authorisation from a radiation protection committee

    Setting up a biobank

    Specific rules for clinical trials with medicines or medical devices

    SKL and LIF – agreements and templates for clinical studies

    Särskilda regler för läkemedel och medicinteknik

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    Consent from study participants

    Access to information from medical records

    Collecting and managing data

    Specific rules for clinical trials with medicines or medical devices

    Särskilda regler för läkemedel och medicinteknik

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    Statistical analysis plan

    Analysis population

    Replacement (imputation) of missing values

    Statistical analysis

    Adjustment analysis

    Subsidiary group analysis and interactions

    Sensitivity analysis

    Interim analysis

    Analysis database and analysis program

    Evaluating the result

    Writing a study report

    Särskilda regler för läkemedel och medicinteknik

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    Writing a scientific article

    Selecting the journal

    Open access

    Särskilda regler för läkemedel och medicinteknik

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    Personal data

    Specific rules for clinical studies using medicines

    Särskilda regler för läkemedel och medicinteknik

The various phases of clinical trials

A clinical trial is conducted according to a study protocol set in advance. A trial may last from a couple of weeks up to a year or more, depending on the question, the disease and the nature of the therapy.

The results from clinical trials constitute an important part of the documentation required to get a medicine approved for sale, and are often a requirement in order to get a medical device CE-marked and marketed. Often, it is also a requirement that companies or researchers carry out trials of the safety of a medicine even following an approval.

The description of the various phases of a clinical trial apply for trials with medicines, but the phases are similar also for medical devices.

Phase 1

Phase 1 often uses healthy study participants, around 20–80 individuals who are usually men, to study the safety of the product. A substance is investigated for any side effects, how the body breaks it down and disposes of it, and what the pharmacological characteristics are. Phase 1 starts by testing a very low dose of a substance, and the dose is then gradually increased. Between each increase, a comprehensive safety evaluation is made.

Phase 2

For Phase 2, study participants are recruited who have the disease or condition that is to be treated with the therapy in question. The number of study participants is still limited, and the patient group should be as homogenous as possible. During Phase 2, a first idea is obtained of the effect of the therapy on a certain disease, and the optimal dose. The new therapy is compared with existing therapies or placebo, and further information about the safety of a substance and any side effects is also obtained.

Phase 3

During Phase 3, large patient groups of between 200 and 3 000 individuals or more are studied, to confirm the effect and safety of a therapy compared to standard therapy or placebo over a longer period. The dose used is the one found most suitable during an earlier phase. The patient groups shall resemble as far as possible the group on which the finished therapy will be used (for example gender, weight and age). So-called “interaction studies” are also carried out, where the reactions to the substance in question of patients who are simultaneously receiving other therapy are looked at.

If the Phase 3 studies are successful, an application can be made to have the therapy approved.

Phase 4

Once the product has begun being marketed, major studies are carried out to map unusual side effects and to monitor the safety, effectiveness and optimal area of use of the therapy.

Approval of medicines

Approvals of new medicines are nearly always based on a joint decision made by several or all EU countries.

An approval does not by itself entail any recommendation that the medicine should be used, but when a medicine is approved then marketing of the product is also approved.

An application for approval of a new medicine includes documentation on pharmaceutical quality, pre-clinical pharmacology and toxicology and the results of clinical studies.

How a medicine is approvedexternal link, opens in new window

Skapad: 2017-11-10
Senast uppdaterad: 2018-11-13 


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