GSK's asthma drug Nucala gets speedy review for rare blood disorder
GlaxoSmithKline’s asthma drug Nucala may not be on the same tier as rival Regeneron’s Dupixent, but it has scored a speedy review for use in a rare blood disorder.
First approved in 2015 for severe eosinophilic asthma, Nucala (known chemically as mepolizumab) targets IL-5. The British drugmaker on Wednesday disclosed that the monoclonal antibody secured priority review from the FDA for patients with hypereosinophilic syndrome (HES) — a group of life-threatening inflammatory disorders characterized by a persistent overproduction of a type of white blood cell called eosinophils.
The US drug regulator has laid out the red carpet for the use of the drug in HES, also having granted fast track and orphan drug designations for the indication. Last year, however, the agency had a decidedly contrasting view on Nucala’s use in patients with COPD, after it failed one late-stage test but cleared another. After an expert panel voted 16 to 3 against approval, the FDA spurned the application, as widely anticipated.
For HES, Nucala was tested in a 108-patient late-stage study. The drug induced a statistically significant reduction of 56% in HES flares, characterized by a worsening of symptoms or exaggerated eosinophil levels requiring an escalation in therapy over the 32-week period, versus 28% in the placebo group — meeting the main goal of the study. It also met a host of secondary trial endpoints, such as the risk of first HES flare over the study period, the annualized rate of HES flares and fatigue scores.
Last month, in a late-stage trial the biologic generated a statistically significant improvement in chronic rhinosinusitis patients with nasal polyps, another indication Dupixent is approved for.
Nucala recorded £210 million ($258 million) in first-quarter sales, benefiting from at-home use application launches worldwide as Covid-19 diminished the ability of patients to visit healthcare facilities. Dupixent generated $855 million over the same period.
“Nucala is not a major competitive threat to Regeneron’s Dupixent—the likely preferred asthma drug near term given physicians’ preference for Dupixent’s safety and efficacy. In our prior survey work, physicians indicated that they expect their usage of Nucala to decline,” Credit Suisse analyst Evan Seigerman wrote in a note last month.
Nucala is believed to work by preventing IL-5 from binding to its receptor on the surface of eosinophils diminishing blood eosinophils, but not eradicating them altogether. Regeneron and Sanofi flagship Dupixent targets IL-4 and IL-13.