Results of the first-ever clinical drug trial using lonafarnib from Merck Inc., for children with Progeria, demonstrate the efficacy of a farnesyltransferase inhibitor (FTI), a drug originally developed to treat cancer. Twenty-eight children from sixteen countries participated in the two-and-a-half year drug trial, representing 75 percent of known Progeria cases worldwide at the time the trial began. Of those, 26 are children with the classic form of Progeria. Treatment consisted of lonafarnib given to children orally, twice-a-day over the course of the study. Results included improvement in one or more of the following areas: Weight: One in three children demonstrated a greater than 50 percent increase in annual rate of weight gain or switched from weight loss to weight gain, due to increased muscle and bone mass. Bone Structure: On average, skeletal rigidity (which was highly abnormal at trial initiation) improved to normal levels after FTI treatment. Cardiovascular: Arterial stiffness, strongly associated with atherosclerosis in the general aging population, decreased by 35 percent. Vessel wall density also improved with treatment.Progeria (also known as "Hutchinson–Gilford Progeria Syndrome", "Hutchinson–Gilford syndrome", and "Progeria syndrome") is an extremely rare genetic disease wherein symptoms resembling aspects of aging are manifested at an early age.