Long‑Term Safety and Tolerability of Benralizumab in Participants with HES, EGPA, or Severe Asthma Continuing Therapy After Prior Study (ROSY‑F Roll‑Over)

The primary objective is to evaluate the long‑term safety and tolerability of benralizumab in participants with hypereosinophilic syndrome, eosinophilic granulomatosis with polyangiitis, or asthma who have completed a previous clinical trial and are deemed by the investigator to continue deriving clinical benefit from ongoing treatment. This assessment aims to characterize adverse event profiles over an extended exposure period, thereby informing the risk–benefit balance of continued therapy in these rare and severe eosinophilic disorders.

The trial enrolled 252 participants of both sexes, including individuals classified as vulnerable, with an age distribution spanning from early childhood through adulthood as indicated by the study’s age range codes. Eligible subjects had a confirmed diagnosis of Hypereosinophilic Syndrome, Eosinophilic Granulomatosis with Polyangiitis, or asthma and had completed the minimum required open‑label extension period of a preceding study, after which the investigator determined continued therapeutic benefit. Additional selection criteria required provision of a signed informed consent form, adherence to contraception requirements per the parent protocol, and an inability to obtain commercially available benralizumab despite clinical indication for its continued use. Participants were required to remain in the study until 12 weeks after the last dose of the investigational product.

The ROSY‑F roll‑over study enrolls participants who have completed the minimum required open‑label extension period of a preceding benralizumab trial and, in the investigator’s judgment, continue to benefit from therapy; all participants must provide a signed informed consent form and comply with contraception requirements per the parent protocol. Eligible individuals receive subcutaneous benralizumab 30 mg administered in a pre‑filled syringe according to the dosing schedule established in the prior study, with ongoing treatment continued until the investigator determines that clinical benefit is no longer present or until study completion. The visit schedule includes an initial screening visit to confirm eligibility, a baseline visit for the first dose, regular follow‑up visits coinciding with each subsequent dose to assess adverse events, concomitant medication use, and clinical status, and a final end‑of‑study visit conducted 8 weeks after the last dose to complete safety monitoring. Participants remain in the study for the full treatment period plus the 8‑week safety follow‑up; involvement may be terminated early in the event of a serious adverse event, emergence of a condition that precludes continued benralizumab administration, pregnancy, or voluntary withdrawal of consent. The trial is a phase 5, category 2 safety evaluation with an anticipated recruitment period from June 2026 to December 2029.

The investigational product is Fasenra 30 mg solution for injection supplied in a pre‑filled syringe. The formulation is a sterile solution for subcutaneous use containing the monoclonal antibody benralizumab. Each administration delivers 30 mg of active substance in a volume consistent with the labeled concentration. Dosing is performed by subcutaneous injection according to the study‑specified schedule.

A second investigational item listed is benralizumab presented as a solution for injection for subcutaneous use. This product contains the same active ingredient as Fasenra and is administered in the same manner, providing 30 mg per dose via subcutaneous injection.

No placebo, comparator drug, or additional experimental therapy is administered in this rollover study. Participants may continue any background therapy deemed necessary by the investigator, provided it does not interfere with the assessment of benralizumab safety and tolerability.

All injections are administered by qualified clinical staff. Dosing records are maintained in the study log to verify adherence to the prescribed schedule. Compliance monitoring includes verification of injection site, documentation of dose administered, and review of any missed or delayed doses at each study visit.