​We are pleased to announce an important update to the IDELVION Connect Copay Program.* In recognition of the ongoing needs of the patient community and our commitment to providing meaningful support, we are increasing the maximum eligible out-of-pocket copay assistance from $12,000 to $20,000 per patient. To enroll, patients and Specialty Pharmacies are encouraged to contact IDELVION Connect at 1-800-676-4266.
 
What is Changing

• Effective, January 1, 2026, CSL has increased the out-of-pocket IDELVION copay coverage up to $20,000 per year for each eligible patient. 

 
What is Not Changing

• IDELVION Copay Support Program helps eligible patients with commercial insurance by assisting with out-of-pocket expenses for IDELVION. Most patients with commercial insurance pay $0 out-of-pocket.
• Both patients and Specialty Pharmacies can contact IDELVION Connect at 1-800-676-4266 to inquire and/or process a copay coverage request.
• If a claim is disputed for any reason, the Specialty Pharmacy is responsible for contacting IDELVION Connect at 1-800-676-4266

 
If you have questions, feel free to contact IDELVION Connect at 1-800-676-4266.

Dear Hemophilia Community Partners,

On December 22, 2025, we shared the very sad news of the passing of a hemophilia A
participant with inhibitors in the marstacimab long-term extension trial. We remain
committed to transparency as we continue to assess what occurred.

The circumstances of this case are multi-factorial – including co-existing conditions, the
participant undergoing a urethroscopic surgical procedure, and use of a bypassing agent as
a concomitant therapy – and we are working to understand these elements as fully as
possible in this clinical setting. We plan to present this information as part of a late-breaker
session at the EAHAD congress on February 6.

As we previously shared, an independent external Data Monitoring Committee oversees all
ongoing marstacimab studies. Based on the current information available, the studies are
continuing as planned and the established benefit/risk profile of marstacimab remains
unchanged. We are continuing to review and assess information on this case as we always
do for our medicines, per established processes.

Thank you for your partnership and for your commitment to the hemophilia community.
​
Sincerely,
The Pfizer Hemophilia Team

Dear Hemophilia Community Partners, 

We are deeply saddened to share that a participant in the long-term extension trial  (B7841007) studying marstacimab in people living with hemophilia A or B with or without inhibitors has passed away in December 2025 following serious adverse events of  cerebellar infarction and subsequent cerebral hemorrhage. On behalf of everyone at Pfizer,  we extend our heartfelt sympathies to the participant’s family, friends, and all those  involved in their care. 

Pfizer, together with the trial investigator and the independent external Data Monitoring  Committee, are actively gathering information to better understand the complex, multi factorial circumstances surrounding this occurrence – including co-existing medical  conditions and concomitant medications – and the causality of the event. The individual, a  patient with hemophilia A and inhibitors, participated in the active treatment phase of the  parent study (B7841005) in 2022 prior to entering the long-term extension study in 2023.  Regulatory authorities and investigators have been informed. 

The safety and well-being of participants in our clinical trials remain our highest priority,  and we are committed to transparency and keeping the community informed as we learn  more. 

​Sincerely, 
​The Pfizer Hemophilia Team