Nucala (mepolizumab) effectively induced remission in about half of patients with eosinophilic granulomatosis with polyangiitis (EGPA) that relapsed or did not respond to treatment, according to results from a Phase 3 clinical trial (NCT02020889).
The study found that Nucala reduced relapse rates and allowed patients to lower their doses of corticosteroids, which make up the standard of care of the inflammatory condition, also known as Churg-Strauss syndrome.
Of 136 patients enrolled in the trial, half were randomized to receive Nucala, while the other half had placebo treatment. The report, “Mepolizumab or Placebo for Eosinophilic Granulomatosis with Polyangiitis,” showed that the treatment caused 28 percent of patients treated with Nucala to have 24 weeks or more of accrued remission.
Findings, published in the New England Journal of Medicine, showed that the number of people in the placebo group with an equal amount of remission time was 3 percent. This suggested that Nucala made it nearly six times more likely to reach that level of remission.
Patients in the trial were treated with 300 mg of Nucala or placebo in subcutaneous injections every four weeks for 52 weeks. Patients also received standard care, and attempted to taper their corticosteroid doses during the study.
Looking at the number of participants in remission at week 36 and 48, it was again obvious that Nucala benefitted a larger proportion of patients; 32 percent were in remission at both junctures. The number for placebo was again 3 percent. With this, the trial met both its primary goals.
The annualized relapse rates were halved in patients receiving Nucala compared to placebo. The study also met all its secondary goals, including the time to first relapse and reductions in glucocorticoid dose. In fact, 12 (18 percent) of Nucala-treated participants could stop corticosteroid treatment completely, compared to 3 percent in the placebo group.
Patients receiving active treatment experienced more severe adverse events than placebo-treated patients. But researchers underscored that many of the adverse events were related to disease worsening, rather than to treatment. Worsening of asthma was the most common serious adverse event, occurring in 3 percent of Nucala-treated and 6 percent of placebo-treated patients.
At this point, researchers do not know why only half the group responded to the treatment.
Nucala, developed by GlaxoSmithKline, is an antibody against interleukin (IL)-5, which has been shown to reduce the infiltration of eosinophil immune cells in people with eosinophilic asthma, for which the drug is approved by the U.S. Food and Drug Administration.