Encysive received another approvable letter for Thelin (sitaxsentan sodium), which is under review for the treatment of pulmonary arterial hypertension (PAH), in March. Investors had hoped that, this time, the drug would sway the regulators. However, the FDA has again issued an approvable letter, in which the regulator states that one of the substantive items raised in the March letter remains unresolved.
In the latest approvable letter, the FDA acknowledged that the unresolved item is a matter of judgment and expressed an openness to consider new arguments to address this remaining item. The FDA again offered the alternative of conducting additional clinical work.
The FDA also provided recommendations on the company’s risk management plan, which Encysive said it views as constructive.