BELGIUM – UCB has announced that zilucoplan was effective in treating the rare autoimmune disease myasthenia gravis in a large Phase III trial just over two years after spending more than US$2 billion to acquire the drug.

Although UCB declined to provide specific numbers, the Belgian pharmaceutical said patients on the drug outperformed placebo on all primary and secondary endpoints, including three different scales used to track symptoms of the complex disease.

According to, the study had 174 patients and found the drug to be “well-tolerated,” with a similar number of serious treatment-emergent adverse events in both the placebo and drug arms.

The company intends to file for approval later this year.

UCB acquired the drug in 2019 when it paid US$2.1 billion from Ra Pharma. The drug was designed to compete with Alexion’s blockbuster Soliris, which is now owned by AstraZeneca.

Zilucoplan targets the same target as Soliris: complement factor 5, a key node in the immune system.

Without actual data, it is impossible to predict where zilucoplan will be able to compete if it is approved. However, the market has already become more crowded in the short time since UCB’s acquisition.

Aside from AstraZeneca’s follow-up drug Ultomiris, Apellis now has an approved complement-targeting competitor called Empaveli, though it has yet to gain approval in myasthenia gravis.

Both Empaveli and zilucoplan are administered subcutaneously rather than intravenously, allowing patients to follow a simpler dosing regimen.

Several companies have also pursued — and in one case received approval for — molecules that block a receptor called Neonatal Fc receptor (FcRn), assisting in the removal of antibodies that contribute to diseases like myasthenia gravis.

UCB, on the other hand, has hedged its bets. The company is also developing rozanolixizumab, a monoclonal antibody for the same indication.

Rozanolixizumab, is already in Phase III trials. It is also working on an extended release form of zilucoplan and an oral complement inhibitor, both of which would be the first of their kind if successful.

Zilucoplan was previously designated as an Orphan Drug by the Food and Drug Administration (FDA) for generalized myasthenia gravis.

Liked this article? Sign up to receive our regular email newsletters, focused on Africa and World’s healthcare industry, directly into your inbox. SUBSCRIBE HERE