The drug repositioning strategy looks at new efficacy of existing medicines.There are merits such as no need to newly synthesize a compound and the optimum amount to be administered, side effects, prohibited items, etc. are already known.It is possible to apply highly safe drugs inexpensively and quickly in clinical practice.For intractable diseases for which therapeutic drugs are expensive or for which effective drugs have not been developed, there are high expectations for an approach to see if any of the drugs already used for other diseases can be expected to be effective.

　This time, we focused on the treatment of osteoporosis and bone fractures. A gene called Runx2 is involved in the differentiation of undifferentiated cells into osteoblasts that form and repair bone.The research team investigated various medicines that have the effect of increasing the activity of the Runx2 gene.When we actually administered it to mouse cells and observed the effect, we found that a drug called lansoprazole was effective.Lansoprazole has been used since 1992 to suppress gastric acid secretion.It was also confirmed that administration to rats with fractures promotes recovery.We have also succeeded in elucidating the mechanism at the molecular level.

　Since no drug has yet been developed to promote bone formation and accelerate fracture treatment, it makes a lot of sense to identify potential substances.Furthermore, the fact that it is a substance that has been used as a pharmaceutical product for over 20 years in each country will be a great advantage for clinical application.