Rigel Pharmaceuticals suffered a blow yesterday when its candidate allergic rhinitis product came out worse than an already-marketed comparator drug in a Phase II clinical trial, sending its stock down by two thirds.
Rigel said its R112 drug was no better than placebo in relieving symptoms in hayfever sufferers, while GlaxoSmithKline’s intranasal corticosteroid Beconase AQ (beclomethasone) demonstrated superior results. The news makes Rigel’s chances of capturing a slice of the $4 billion dollar allergic rhinitis market look increasingly remote.
Rigel chief executive James Gower said the results came as a surprise as an earlier Phase II study of R112 demonstrated a statistically significant reduction in the symptoms associated with allergies.
R112, Rigel’s lead drug candidate, is an intranasally-administered inhibitor of Syk kinase, which is involved in immunoglobulin E signalling in mast cells.
Rigel also has an early-stage collaboration with Pfizer focusing on the development of Syk kinase inhibitors for the treatment of asthma and other respiratory diseases. As yet Pfizer has not selected a candidate to take into drug development.