Study to Evaluate the Long- Term Safety and Efficacy of Luspatercept in Subjects Who Received at Least One Dose of Luspatercept in the Compassionate Use Phase

Observational Study to Evaluate the Long- Term Safety and Efficacy of Luspatercept in Subjects Who Received at Least One Dose of Luspatercept in the "Compassionate" Use Phase

Luspatercept represents the first and only erythroid maturation agent (EMA) approved by the European Commission (EC) and the Food and Drug Administration (FDA) capable of enhancing advanced erythrocyte maturation.

The efficacy of luspatercept was demonstrated in the phase III clinical trial called "BELIEVE." More than 200 Italian patients with transfusion- dependent beta thalassemia aged ≥18 years who had no approved therapeutic alternatives to improve their clinical course were considered eligible for the 'compassionate' use program related to luspatercept and most of them received at least one dose of the drug before it was dispensed by the National Health System (NHS), after approval by the pharmaceutical company and the Ethics Committee of the Clinical Center in which they were being followed.

One month after the publication in the Official Gazette of the Italian Republic of the AIFA determination of price and reimbursement for the treatment indication covered by the program, those who were still on treatment and were, in clinical judgment, eligible to continue it, continued to receive the drug through dispensation by the NHS.

Because access to the compassionate phase was less restrictive than access to that in formal clinical trials and the patients included particularly representative of real life, collecting data on clinical characteristics at baseline, safety, and efficacy is critical to enriching the information available on this new therapy. Continuing to collect efficacy, safety, and tolerability information beyond the compassionate phase is also essential for a more complete and accurate assessment, given the short duration of 'compassionate' treatment for a portion of the patients under study.

Inclusion criteria:

- Subjects who received at least one dose of luspatercept in the compassionate phase

Exclusion Criteria:

- Subjects who are not willing or able to sign the informed consent.