The Sunday Telegraph says up to 6,000 posts would be eliminated around the world, while The Observer said as many as 10,000 jobs could go – 10 per cent of the company’s global work force.
Glaxo spokespeople could not immediately be reached for comment on Sunday.
Major pharmaceutical manufacturers are facing increasing competition from generic rivals to their best-selling drugs.
Like its rivals, Glaxo has already been cutting jobs to help make savings. The company aims to shave 700 million pounds ($1 billion) off its annual cost base by 2010.
Rival AstraZeneca last week confirmed plans to slash another 6,000 jobs.