Polymyxin-containing medicines

  • Procedure started
  • Under evaluation
  • CHMP opinion
  • European Commission final decision
Current status
European Commission final decision


Recommendations issued for safe use in patients with serious infections resistant to standard antibiotics

On 23 October 2014 the European Medicines Agency (EMA) completed a review of the safety and effectiveness of products containing the antibiotics colistin or colistimethate sodium (known as polymyxins) and recommended changes to their product information to ensure safe use in the treatment of serious infections that are resistant to standard antibiotics.

Polymyxin-based products have been available since the 1960s, but their use quickly decreased due to the availability of antibiotics with fewer potential side effects. Due in part to this limited use, colistimethate sodium has retained activity against a number of bacteria which have become resistant to commonly used antibiotics. This has led to a resurgence in recent years in the use of polymyxins in patients with few other options. However, current experience has raised concerns that the existing product information, in particular relating to dosing and the way the medicine is handled in the body (pharmacokinetics), might need updating. The European Commission therefore requested the EMA to review the available data and make recommendations on whether the marketing authorisations for these medicines should be changed and the product information amended appropriately.

The Agency's Committee for Medicinal Products for Human Use (CHMP) reviewed the available data about the pharmacokinetics, effectiveness and safety of these medicines. The review considered products given by injection or inhaled as a liquid into the lungs (systemic use) containing colistimethate sodium, which is converted to the active substance colistin in the body. Products taken by mouth (which mainly contain colistin and are not absorbed into the body in significant amounts but act locally on the gut) and those applied externally were not covered in this review.

The CHMP concluded that injection or infusion (drip) of colistimethate sodium should be reserved for the treatment of serious infections due to susceptible bacteria, in patients whose other treatment options are limited. The medicine should be given with another suitable antibiotic where possible. The Committee recommended that doses should always be expressed in international units (IU) but because doses of colistimethate sodium can be expressed in different ways a conversion table should be included in the product information. Critically ill patients should be given a higher starting dose (loading dose) to provide an effective level of the antibiotic in the body more quickly. Although data were very limited, the Committee recommended doses for use in patients with kidney problems and in children, and provided guidance on dosage in adults when given directly into fluid surrounding the brain or spinal cord (intrathecal or intraventricular injection).

CHMP concluded that colistimethate sodium may also be given by inhalation or in a nebuliser to treat ongoing (chronic) infections with the bacterium Pseudomonas aeruginosa in patients with cystic fibrosis. (Products for inhalation as a dry powder have a different dosage and distribution in the body, and were not affected by the conclusions of the review.)

The CHMP opinion was forwarded to the European Commission, which issued a final decision valid throughout the EU on 15 December 2014.

Key facts

About this medicine
Approved name
Polymyxin-containing medicines
International non-proprietary name (INN) or common name
colistimethate sodium
Associated names
About this procedure
Current status
European Commission final decision
Reference number
Article 31 referrals

This type of referral is triggered when the interest of the Union is involved, following concerns relating to the quality, safety or efficacy of a medicine or a class of medicines.

Key dates and outcomes
CHMP opinion date
EC decision date

All documents

Opinion provided by Committee for Medicinal Products for Human Use

  • List item

    Polymyxin Article-31 referral - Annex III (PDF/178.17 KB)

    First published: 24/10/2014
    Last updated: 05/01/2015

  • European Commission final decision

  • List item

    Polymyxin Article-31 referral - European Medicines Agency completes review of polymyxin-based medicines (PDF/94.61 KB)


    First published: 24/10/2014
    Last updated: 05/01/2015

  • List item

    Polymyxin Article-31 referral - Annex I (PDF/183.37 KB)

    First published: 05/01/2015
    Last updated: 05/01/2015

  • List item

    Polymyxin Article-31 referral - Annex II (PDF/38.39 KB)

    First published: 05/01/2015
    Last updated: 05/01/2015

  • List item

    Polymyxin Article-31 referral - Assessment report (PDF/249.15 KB)

    First published: 05/01/2015
    Last updated: 05/01/2015

  • Description of documents published

    Please note that some of the listed documents apply only to certain procedures.

    • Overview - lay-language summary of the stage of the procedure
    • Notification – a letter from a Member State, the European Commission or the marketing authorisation holder requesting the initiation of the procedure
    • Scientific background – further background information from the triggering Member State on the issues leading to the initiation of the procedure (if applicable)
    • List of questions – questions agreed by the Committee requesting further information from the marketing authorisation holder(s) / applicant(s) to evaluate the issues identified
    • Timetable for the procedure – agreed timeframe to respond to the list of questions, to assess the issues and to adopt a conclusion
    • List of medicines concerned by the procedure – medicine(s) / active substance(s) concerned, and marketing authorisation holder(s) / applicant(s)
    • List of questions to be addressed by the stakeholders – call for data to be submitted by stakeholders (e.g. healthcare professionals, patient organisations, individual patients) (if applicable)
    • Stakeholder submission form – form to be used by stakeholders to submit data (if applicable)
    • Scientific conclusions – scientific conclusions of the PRAC and/or CHMP and/or CMDh
    • Assessment report – PRAC or CHMP assessment and conclusions on the issues investigated, including divergent positions (if applicable)
    • Divergent positions – divergent positions of the CHMP or CMDh members for pharmacovigilance procedures (if applicable)
    • Changes to the summary of product characteristics, labelling and package leaflet (amended sections or fully revised version) (if applicable)
    • Condition(s) to the marketing authorisation(s) – condition(s) for the safe and effective use of the medicine(s) (if applicable)
    • Condition for lifting the suspension – condition to be fulfilled for the suspension of the marketing authorisation(s) to be lifted (if applicable)
    • Timetable for implementation of CMDh position – agreed timeframe to submit and finalise the variation(s) implementing the outcome of the procedure (if applicable)

    Note that older documents may have different titles.

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