GlaxoSmithKline will shed around 380 jobs as one of its research units in Essex closes.
The pharmaceutical giant will make one-third of the workforce redundant after projects for pain relief, anxiety and depression drugs end at GlaxoSmithKline in Harlow, the BBC reports.
The company said the plant was to remain open.
A consultation period was under way but no new research projects would be started, a spokeswoman said.
The firm also said it would continue restructuring to bring in £500m of savings by 2012 but would “try to preserve jobs” wherever possible.