GlaxoSmithKline is set to buy Human Genome Sciences for $3.6 billion

After months of wrangling, GlaxoSmithKline (GSK) has found enough common ground with Human Genome Sciences (HGS) for the two to sign up to a $3.6 billion (£2.3 billion) takeover deal.

GSK announced a $2.6 billion bid in April but was immediately turned away. This prompted the company to take the offer directly to the HGS shareholders.

The two companies have worked together for over 20 years on several products, including the development of benlimumab, marketed as Benlysta, the first new treatment for lupus erythematosus in half a century. Benlimumab, a monoclonal antibody, was approved by US authorities in March 2011, and analysts are predicting peak sales of $3–7 million per year.

GSK says the deal will lead to cost savings across the combined business of $200 million.