October 15, 2005 (Vol. 25, No. 18)
Zyflo Asthma Treatment Receives FDA Approval for sNDA
The FDA approved Critical Therapeutics’ (www. crtx.com) supplemental New Drug Application (sNDA) to manufacture and market Zyflo (zileuton tablets), which is indicated for the prevention and chronic treatment of asthma in patients 12 years of age and older. Zyflo is expected to be available to patients before the end of October 2005.
Zyflo inhibits the production of 5-lipoxygenase (5-LO), the main enzyme responsible for the production of leukotrienes, a family of inflammatory mediators that can trigger asthma symptoms, including inflammation, swelling, bronchoconstriction, and mucus secretion.
Kate Winkler, Ph.D., senior executive director, healthcare and life sciences research at Global Crown Capital, rates the stock as overweight. “Critical Therapeutics has an attractive set of products in development that target inflammatory mediators via distinct and scientifically astute mechanisms.
“We believe that collectively these products have opportunities addressing the underlying pathologies of prevalent but complicated inflammatory diseases. Zileuton sales should commence next month, and by early 2007 the 2x day formulation could expand its market substantially.
“A highlight is the unrealized clinical and market potential for zileuton (Zyflo). The drug inhibits 5-lipoxygenase (5-LO), a central molecular grandparent of several families of pro-inflammatory molecules, thereby inhibiting their production. We expect that zileuton will see use beyond acute asthma; preliminary data points to efficacy in autoimmune diseases (rheumatoid arthritis and lupus),” says Dr. Winkler.
“Also, critical care is an attractive specialty market. Concentrated prescribers and premium pricing tolerated in the no holds barred’ ICU setting make it a lucrative medical market despite generating lower sales volumes. Furthermore, in the aftermath of the Vioxx recall, there is clear need for new anti-inflammatory agents that exploit different physiologic mechanisms.”
Additionally, another product in its pipline, anti-HMGB1, “is a promising approach to sepsis. Usually by the time patients are septic, it’s too late to use most anti-inflammatory agents whose targets are no longer contributing to the reaction. HMgB1 promotes inflammation late in the reaction and thereby remains a viable target at the time of diagnosis.”
For the year ending December 31, 2005, the company expects net cash expenditures of between $50 million and $55 million, net of cash received from any product sales and payments received under collaboration agreements.
This is an increase from the company’s previous guidance of $45 million to $50 million for 2005 and is primarily due to Phase IV studies to support the marketing position of Zyflo and increased costs related to the scale up and manufacture of zileuton CR.
“Based on the drug’s pharmacologic profile, I believe Zyflo may be an effective treatment for patients already taking beta agonists and high-dose steroids that have failed to sufficiently control their asthma symptoms,” says Sally Wenzel, M.D., an invesigator for Zyflo and professor of medicine at the National Jewish Medical and Research Center.