National Patient Safety Alert: Discontinuation of Promixin® (colistimethate) 1-million unit powder for nebuliser solution unit dose vials

National Patient Safety Alert: Discontinuation of Promixin® (colistimethate) 1-million unit powder for nebuliser solution unit dose vials

National Patient Safety Alert Reference Number: NatPSA/2025/001/DHSC

Date issued: 17 March 2025

Explanation of identified safety issue

Promixin® (colistimethate) 1-million-unit powder for nebuliser solution unit dose vials (UDVs) are being discontinued from early May 2025, with stocks anticipated to be exhausted by this date.

As a result of the discontinuation of I-neb devices, discs and consumables from an external manufacturer, which are compatible with Promixin® (colistimethate) 1million unit powder for nebuliser solution unit dose vials, it is no longer viable to manufacture further supplies of the drug.

Promixin® (colistimethate) 1million unit powder for nebuliser solution unit dose vials are licensed for the treatment of adult and paediatric chronic pulmonary infections due to Pseudomonas aeruginosa in patients with cystic fibrosis. This treatment may also be prescribed for the treatment of Pseudomonas aeruginosa colonisation and infection in adult and paediatric patients with non-cystic fibrosis bronchiectasis or bronchial sepsis.

Colicym® (colistimethate) 1million-unit powder for nebuliser solution unit dose vials are available and can support an increase in demand.

Colomycin® (colistimethate) 1million-unit and 2million-unit powder for solution for injection, infusion or inhalation vials are in limited supply until mid- April 2025 and late March respectively and are currently unable to support any increase in demand until the resupply dates.

The SPS Medicines Supply Tool provides an overview of the supply situation and will be updated if there are subsequent changes to this communication, including resupply dates.

Actions required

Actions to be completed by 30/04/2025

Primary and secondary care providers:

1. Do not initiate new patients on Promixin® 1-million-unit powder for nebuliser solution UDVs.
2. Pro-actively identify and review all patients currently prescribed Promixin® 1million unit powder for nebuliser solution UDVs and immediately refer them to their respiratory specialist to switch to an alternative colistimethate preparation.

Respiratory specialists within secondary care should consider the patients diagnosis and:

1. Consider prescribing Colicym® 1-millionunit powder for nebuliser solution unit dose vials. ^{NOTE A}
2. Where the above is not suitable, prescribe Colomycin® 1-million- or 2- million-unit powder for solution for injection, infusion or inhalation. ^{NOTE B}
3. When switching colistimethate products, ensure patients are provided with appropriate education and training to ensure they can use the new nebuliser device and administer the correct dose.
4. Once switched to an alternative colistimethate product, clinicians in secondary care should ensure this is documented and shared with primary care, for on-going treatment, where applicable.
5. Homecare providers should ensure affected patients are notified of any changes to their prescribed medicines and are aware of any changes to their homecare provisions.

Additional information

Clinical Information

When switching patients from Promixin® to an alternative colistimethate preparation, individual summary of product characteristics (SmPCs) should be consulted as the products vary in indications, dosing and administration. Switching from Promixin® to alternative colistimethate preparations should be carried out under specialist supervision to ensure patients understand how to use the new nebuliser device and administer the correct dose. The respiratory team should risk assess the need for a test dose and ensure if needed this is administered under clinical supervision.

All equipment (diluents, nebuliser device and needles) will be supplied via Respiratory teams.

Note A: CAUTION: Colomycin® is licensed for administration via both the intravenous and inhaled route. Colicym® is only licensed for nebulisation. Care should be taken to ensure the correct product has been selected when dispensing and administering colistimethate products.

Note B: Colomycin® (colistimethate) 1-million and 2-million unit powder for solution for injection, infusion or inhalation vials are in limited supply until mid-April and late March 2025 respectively and unable to support an increase in demand until these dates.

Current stock should be reserved for patients already maintained on this treatment or for those who require treatment via the intravenous route.

References:

1. SmPC Promixin® 1 million international units (IU) powder for nebuliser solution
2. SmPC Colomycin® 1million international units (iu) powder for solution for injection, infusion or inhalation
3. SmPC Colicym® powder for nebuliser solution
4. BNF Colistimethate sodium
5. BTS Guideline for bronchiectasis in adults
6. NICE: Bronchiesctasis (non-cystic fibrosis), acute exacerbation: antimicrobial prescribing
7. SPS Purchasing for safety
8. I-neb AAD System User guide

Please see full guidance in the alert.