selexipag and Vascular-Diseases

Systemic sclerosis (SSc) is burdened by Raynaud phenomenon (RP) and digital ulcers (DUs), and sometimes standard vasoactive therapies are ineffective or contraindicated. Selexipag is an oral selective IP prostacyclin receptor agonist approved for the treatment of SSc-related pulmonary arterial hypertension. We aimed to evaluate the clinical and instrumental efficacy of selexipag in SSc digital vasculopathy.. Patients with SSc with severe digital vasculopathy refractory or with contraindication to all other vasoactive therapies were administered selexipag. RP- and DU-related clinical outcomes were evaluated, and digital perfusion was assessed by laser speckle contrast analysis (LASCA), all at baseline and after 3 months.. Selexipag was administered to 9 patients with SSc (66.6% female, mean age 52.3 [SD 16.6] yrs). One patient had to stop the drug because of adverse effects. After 3 months of selexipag administration, there was a significant reduction in RP daily episodes (. Selexipag showed good potential for the treatment of SSc digital vasculopathy. Our results are certainly preliminary, yet quite encouraging. New trials for the evaluation of selexipag efficacy in SSc digital vasculopathy are needed.

Topics: Female; Fingers; Humans; Lasers; Male; Middle Aged; Raynaud Disease; Scleroderma, Systemic; Skin Ulcer; Vascular Diseases

Prostacyclin (PGI(2)) and its analogs are useful for the treatment of various vascular disorders, but their half-lives are too short for widespread clinical application. To overcome this drawback, we have synthesized a novel diphenylpyrazine derivative, 2-[4-[(5,6-diphenylpyrazin-2-yl)(isopropyl)amino]butoxy]-N-(methylsulfonyl)acetamide (NS-304), a prodrug of the active form [4-[(5,6-diphenylpyrazin-2-yl)(isopropyl)amino]butoxy]acetic acid (MRE-269). NS-304 is an orally available and potent agonist for the PGI(2) receptor (IP receptor). The inhibition constant (K(i)) of MRE-269 for the human IP receptor was 20 nM; in contrast, the K(i) values for other prostanoid receptors were >2.6 microM. MRE-269 was therefore a highly selective agonist for the IP receptor. The plasma concentrations of MRE-269 remained near peak levels for more than 8 h after oral administration of NS-304 to rats and dogs, and NS-304 increased femoral skin blood flow in rats in a long-lasting manner without affecting the hemodynamics. These findings indicate that NS-304 acts as a long-acting IP receptor agonist in vivo. The continuous vasodilation evoked by NS-304 was not attenuated by repeated treatment, indicating that NS-304 is unlikely to cause severe desensitization of the IP receptor in rats. Moreover, a microdose pharmacokinetic study in which NS-304 was orally administered to healthy male volunteers showed conversion of NS-304 to MRE-269 and a long plasma elimination half-life for MRE-269 (7.9 h). In conclusion, NS-304 is an orally available and long-acting IP receptor agonist prodrug, and its active form, MRE-269, is highly selective for the IP receptor. Therefore, NS-304 is a promising drug candidate for various vascular diseases, especially pulmonary arterial hypertension and arteriosclerosis obliterans.

Topics: Acetamides; Administration, Oral; Animals; Dogs; Femur; Half-Life; Humans; Male; Prodrugs; Pyrazines; Rats; Receptors, Epoprostenol; Regional Blood Flow; Vascular Diseases; Vasodilation