Sept 18 (Reuters) - Healthcare company Organon

said on Wednesday it has agreed to acquire skin therapy

developer Dermavant, a unit of Roivant, for up to $1.2

billion.

Organon will make an upfront payment of $175 million, as

well as milestone payments of $75 million and up to $950 million

upon achievement of certain commercial milestones.

Dermavant's VTAMA psoriasis cream was approved by the U.S.

Food and Drug Administration in May 2022. Psoriasis is a common

chronic inflammatory skin disease.

The company expects to close the transaction in the fourth

quarter of this year.