Important Update: Erwinase® Supply Status and Treatment Guidance (Updated 5 December 2025)

Following the confirmation of manufacturing cessation by Porton Biopharma Limited (PBL) of Erwinase® (crisantaspase (L-asparaginase Erwinia chrysanthemi)), Clinigen has been informed by PBL that there will be a delay in the availability of new stock, and it is expected that shortages and supply constraints will occur in the UK and throughout the EU into February 2026. We recognise the implications this news holds for patients and for the clinical community dedicated to treating patients with acute lymphoblastic leukaemia (ALL).

As the exclusive global distributor of Erwinase, Clinigen's paramount focus is on supporting treatment continuity. Clinigen is aware that shortage notifications will be submitted to the relevant regulatory authorities and will be triaging all supply until we have further information on the availability of new batches. 

Clinigen is sharing the following guidance to help manage existing stock:

  • Prioritise High Risk patients.
  • Maximise dose availability per vial by scheduling treatment of several patients on the same day.
  • Where available, use of Therapeutic Dose Monitoring.
  • Adjustments to existing clinical protocols in line with evolving supply and alternative treatment strategies.

We will provide stakeholders with regular updates to ensure you are informed of developments regarding supply and treatment guidance.

Background: Manufacturing Cessation

As previously announced, Porton Biopharma Limited (PBL), the manufacturer of Erwinase® (crisantaspase (L-asparaginase Erwinia chrysanthemi)), has confirmed that it will be ending production of the medicine towards the end of 2025. Clinigen understands there will be no future source of manufacturing. 

Erwinase plays an important role in the treatment of patients with acute lymphoblastic leukaemia (ALL) who are unable to tolerate E. coli-derived asparaginase. We know how vital this treatment is.

As the exclusive global distributor of Erwinase, Clinigen has been working closely with PBL and preparing for this scenario and take this moment to reassure healthcare professionals and partners that the product has a three-year shelf life. 

Clinigen is working closely with PBL and regulatory authorities to support the orderly and responsible withdrawal of marketing authorisations and to support patient access during this process.

Clinigen is already working with healthcare professionals, treatment protocol leaders and regulators to support a smooth and coordinated transition. This includes exploring suitable alternatives and helping ensure continuity of care wherever Erwinase has been part of the treatment pathway. 

Our commitment remains the same: to ensure that healthcare professionals have access to the treatments they need for their patients, when and where they need them. 

If you have any questions about Erwinase supply, get in touch at: 

medicineaccess@clinigengroup.com

 

The sole purpose of this statement is to inform Health Care Professionals of the current position regarding Erwinase supply. While this statement has been prepared in good faith, Clinigen does not accept any liability and does not make any representation or warranty, express or implied, with respect to the information in this statement. This statement includes forward-looking statements, that are based on Clinigen's current views and assumptions. Clinigen assumes no obligation to update any information or forward-looking statement contained herein, save for any information we are required to disclose by law.