Rigel Initiates Multi-Dose Safety Trial of R112 for Allergic Rhinitis
Wednesday September 10, 6:41 pm ET
Trial Designed to Establish Safety of R112 for Longer-Term Use
SOUTH SAN FRANCISCO, Calif., Sept. 10 /PRNewswire-FirstCall/ -- Rigel Pharmaceuticals, Inc. (Nasdaq: RIGL - News) today announced that it has initiated a multi-dose safety trial of R112, an experimental drug to treat allergic rhinitis. The goal of this trial is to establish the longer-term, multi-dose safety of R112 in various dosing regimens. Results of this trial are expected by January 2004 and will allow Rigel to enter into broader, longer-term, multi-dose efficacy trials in the first half of 2004.
In late July, Rigel released the results of a Phase I/II study which evaluated the efficacy and safety of a single intra-nasal administration of R112 in volunteers with asymptomatic seasonal allergic rhinitis. The study demonstrated significant improvement or consistent positive trends in reducing the release of chemical mediators involved in mast cell activation, one of the earliest steps in the initiation of an inflammatory response in allergy and asthma. Additionally, with only a single dose of R112, a correlation between reductions in key mediators and improvements in some allergy symptoms was established. No clinically significant adverse effects were attributed to R112 during this trial or any prior clinical trial.
"R112 may offer a new, comprehensive treatment strategy for allergic inflammation by potentially blocking all major chemical mediators of inflammation involved in mast cell responses and may provide an important, potentially first-line drug, for the treatment of allergic rhinitis," said Donald Payan, MD, Rigel's Chief Scientific Officer and Executive Vice President.
"The multi-dose safety trial is an important next step in the development of this drug and is an indicator of our belief in its potential," said Elliott Grossbard, MD, Rigel's Senior Vice President of Medical Development.
How R112 Works and Its Possible Advantages
R112 enters mast cells, binds to an intracellular target and interrupts the signal from the IgE receptor, thus preventing downstream signaling and subsequent chemical mediator release. However, unlike common allergy drugs such as antihistamines or antileukotrienes that block only a single mediator, R112 is designed to block all of the major pathways that are triggered in an allergic attack, potentially making R112 a more effective and comprehensive drug. Currently, steroids are the major class of drugs that are able to block multiple mediators in the allergic response, but these have a slow onset of action. In the Phase I/II trial, R112 began to diminish chemical mediator release within minutes after allergen challenge. In addition, steroids need to be used selectively due to their global blocking of immune function. R112 is delivered intra-nasally and no systemic exposure of R112 has been detected in any intra-nasal administration in the two human trials conducted. |
