Cyclosporins are cyclic polypeptide macrolides that were originally derived from the soil fungus Tolypocladium inflatum. Cyclosporine (also known as cyclosporine A) was discovered by Sandoz and developed for the tretment of immune disorders. The drug was approved by FDA for such diseases as Rheumatoid Arthritis, Psoriasis (Neoral), Keratoconjunctivitis sicca (Restasis) and prevention of transplant rejections (Neoral and Sandimmune). Cyclosporine’s primary immunosuppressive mechanism of action is inhibition of T-lymphocyte function. Upon administration cyclosporine binds to cyclophilin A and thus inhibits calcineurin, leading to immune system suppression.

Rioprostil is a methylprostaglandin E1 analog. Rioprostil inhibits gastric acid secretion and enhances the gastric mucus-bicarbonate barrier. In peptic ulcer cases, it facilitates the healing process and the elimination of pain. Rioprostil can also be used to prevent recurrence of duodenal ulcers. However, its development has been discontinued in 2000.