According to three people who are familiar with the situation, Astellas Pharma Inc. is looking to sell its dermatology asset. The value of said portfolio of the Japanese drugmaker is around US$500 million to US$1 billion.

DC Advisory, a London based investment bank was hired by Astellas to work on the sale of its assets. This was according to two sources asking not to be named as they are not permitted to speak to the press.

Astellas dermatology portfolio includes a drug to treat eczema. This drug is called Protopic. The company's derma unit sells products all over the world.

Japan's Astellas has US$23 billion market capitalization. It is discussing breaking up the business and selling the pieces to different parties. The intention of which is to generate greater premium. The move to break up the portfolio makes sense as the US patent partner for Protopic is set to expire next year.