May 19 (Reuters) - Achillion Pharmaceuticals Inc said it will collaborate with Johnson & Johnson to develop and market one or more of its hepatitis C drugs.

Achillion will be eligible for milestone payments of up to $1.1 billion related to the development, regulatory approval and sales of the drugs.

Johnson & Johnson will also invest $225 million in Achillion in return for about 18.4 million unregistered shares at $12.25 per share.

(Reporting by Amrutha Penumudi in Bengaluru; Editing by Don Sebastian)