Ultomiris More Cost-effective Than Soliris for aHUS Patients in US, Study Finds

Ultomiris (ravulizumab) is expected to be more cost-effective than its predecessor Soliris (eculizumab) as a treatment for atypical hemolytic uremic syndrome (aHUS) in the U.S., a new study indicates.

The study, “A US cost-minimization model comparing ravulizumab versus eculizumab for the treatment of atypical hemolytic uremic syndrome,” was published in the Journal of Medical Economics. It was funded by Alexion Pharmaceuticals, which developed Soliris and Ultomiris.

aHUS is caused by abnormal activation of a group of immune proteins called the complement system. Soliris and Ultomiris are humanized antibodies that block complement activation.

Both of these medications are approved for the treatment of aHUS in the U.S. and other countries, and both are administered by infusion into the bloodstream. While no clinical trials have directly compared the two treatments, analyses of separate trials have suggested that both are similar in terms of efficacy and safety profile.

Although they are similar in many respects, a key difference between the two medications is that Ultomiris is not cleared from the body as quickly as Soliris, requiring less frequent infusions.

In the new study, researchers from Alexion and elsewhere developed a cost-minimization model (CMM) to evaluate cost differences between the two medications. Conceptually, a CMM is a mathematical model that aims to identify the least expensive treatment option, when outcomes (i.e., safety and efficacy) are virtually identical.

The model used data from previous clinical trials of the two medications to estimate lifetime costs, or the total amount expected to be accrued by a person who lives to be 100 years old. The researchers calculated cost differences with or without a 3% discount (this value was chosen based on previously published research).

With the discount, total costs for Ultomiris were 32.4% lower than for Soliris to treat adult patients. Without the discount, the cost of Ultomiris was 32.6% lower than that of Soliris.

The estimated total lifetime cost, with the discount, was $17,979,007 for Soliris and $12,148,748 for Ultomiris — meaning Ultomiris was associated with a cost saving of $5,830,260. Without the discount, the lifetime cost for Soliris was $37,429,898 and $25,224,763 for Ultomiris, revealing a cost saving of $12,205,135 for Ultomiris treatment.

For both therapies, cost on-treatment was the biggest contributor to the overall cost, whereas combined costs associated with discontinuation, relapse, and post-relapse accounted for about 5% of the total cost.

“Ravulizumab [Ultomiris], which offers an effective treatment for patients with aHUS with a favorable safety profile, was shown to provide substantial cost savings compared with eculizumab [Soliris],” the researchers concluded.

Similar findings were found for pediatric patients: the total treatment costs for Ultomiris were 35.5% (discounted) and 34.0% (undiscounted) lower than for Soliris in individuals 18 and younger. Because pediatric patients are younger and, therefore, expected to live longer, total lifetime costs were higher in the pediatric analysis, though the overall trend in costs was comparable to the findings in adults.

Additional analyses considering specific scenarios — for example, assuming that all patients had been previously treated — found similar results for adult and pediatric patients.

“In all scenarios tested … ravulizumab remained cost-saving compared with eculizumab,” the researchers wrote. “Even with the most conservative estimates for patient demographics/disease characteristics and discontinuation and relapse parameters, ravulizumab was associated with savings compared with eculizumab.”

Notably, the model used in the study assumes a “typical” aHUS patient: “the results produced are reflective of costs averaged across patients,” the researchers wrote, stressing that there will be person-to-person variation in costs with treatment. The model also makes many assumptions about disease progression and discontinuation rates, which may not apply to any individual patient.