The Food and Drug Administration (FDA) has approved a new 100mg/mL formulation of Ultomiris® (ravulizumab-cwvz; Alexion Pharmaceuticals) for the treatment of adults with paroxysmal nocturnal hemoglobinuria (PNH) and for atypical hemolytic uremic syndrome (aHUS) to inhibit complement-mediated thrombotic microangiopathy (TMA) in adults and pediatric patients. 

Ultomiris, a long-acting complement inhibitor, works by specifically binding to the complement protein C5, inhibiting its cleavage to C5a and C5b, thereby preventing the generation of the terminal complement complex C5b9. The product is currently available as a 300mg/30mL (10mg/mL) strength solution in single-dose vials.

The approval was based on a comprehensive chemistry, manufacturing and control submission and a supplementary clinical data that showed comparable safety and efficacy data between Ultomiris 10mg/mL and 100mg/mL. Findings showed that the 100mg/mL formulation required an infusion time of 0.4 to 1.3 hours depending on body weight compared with 1.3 to 3.3 hours for the 10mg/mL formulation. Ultomiris 100mg/mL reduced the average annual infusion times by approximately 60% compared with the 10mg/mL formulation.

The new 100mg/mL formulation of Ultomiris is expected to be available within the next few days in 3mL and 11mL single-dose vials for intravenous infusion. The Company will continue to supply the 10mg/mL formulation of Ultomiris until mid-2021, at which time it will be removed from the market.

With regards to safety, the most common adverse events include upper respiratory tract infections, diarrhea, nausea, vomiting, headache, hypertension, and pyrexia. Ultomiris carries a Boxed Warning for severe meningococcal infections and is only available under a Risk Evaluation and Mitigation Strategy (REMS) program that prescribers are required to enroll in.

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“We have seen the significant clinical benefits Ultomiris has demonstrated for patients, through its complete C5 inhibition and sustained efficacy,” said Jamile Shammo, MD, FASCP, FACP, Professor of Medicine and Pathology, Department of Internal Medicine, Rush University Medical Center. “Based on the scientific evidence presented, the advanced formulation demonstrated comparable safety and efficacy to the original formulation, with the additional benefit of significantly shorter infusion times. This reduced treatment burden is important to consider for patients, as it has the potential to make a meaningful difference in their lives.”

Additionally, the Company plans to submit regulatory filings for a subcutaneous formulation of Ultomiris in the third quarter of 2021. Ultomiris is also being investigated in phase 3 studies for the treatment of coronavirus disease 2019 (COVID-19). 

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  1. Alexion receives FDA approval for new advanced formulation of Ultomiris® (ravulizumab-cwvz) with significantly reduced infusion time. [press release]. Boston, MA: Alexion Pharmaceuticals; October 12, 2020. 
  2. Alexion receives CHMP positive opinion for New Advanced Formulation of Ultomiris® (ravulizumab-cwvz) with significantly reduced infusion time. [press release]. Boston, MA: Alexion Pharmaceuticals; September 21, 2020.
  3. Ultomiris [package insert]. Boston, MA: Alexion Pharmaceuticals; 2020.