Important Update: Erwinase® Supply Status and Treatment Guidance (Updated 27 April 2026)

Following confirmation from Porton Biopharma Limited (PBL) of the cessation of manufacturing of Erwinase® (crisantaspase [L asparaginase Erwinia chrysanthemi]), and in light of recent supply notifications, Clinigen would like to confirm that limited stock availability has resumed for EU licensed markets. Please note that this distribution represents the final batch release of Erwinase®.

Clinigen is actively engaging with relevant regulatory authorities to explore all potential pathways to support a structured and controlled transition of care. Our priority is to ensure continuity of patient management while minimising disruption to clinical practice. Specifically, our objectives are to:

  • Provide aligned clinical guidance: Develop and disseminate clear, timely advice for healthcare professionals regarding the anticipated timelines for changes in treatment strategies, with patient safety and clinical outcomes as the foremost considerations. This will include guidance on the appropriateness of initiating new patients on Erwinase®.
  • Support protocol adaptation: Assist clinical teams in making necessary updates to existing treatment protocols in response to evolving supply circumstances and alternative therapeutic strategies.
  • Enable an informed transition: Ensure the clinical community is equipped with the appropriate resources, information, and support to manage this transition effectively and confidently.

In relation to the above, Clinigen suggest that hospitals now consider ordering the complete treatment course at the time of treatment initiation for any new patients.

Clinigen will continue to provide regular updates to stakeholders as further information becomes available regarding supply status and clinical guidance. Our aim is to ensure transparency and to support you throughout this transition.

We sincerely thank you for your continued commitment to patient care. Through proactive planning, close collaboration with regulatory bodies, and clear communication, we remain confident in our ability to support the healthcare community responsibly during this period of change.

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.