SUMMIT - Merck Pharmaceuticals has announced it won't be moving its world headquarters into Summit and instead will cut its overall head count by 20 percent.

Whitehouse Station-based Merck announced those major layoffs on Tuesday.

The drug maker says it'll be eliminating 8,500 positions as part of its more focused research and development plan.

The cuts follow 7,500 layoffs that the company had already announced.

Merck hopes to save $1 billion of that by the end of next year with the move and a total of $2.5 billion in the long run.

The transition is expected to begin next year and be completed by 2015.