Anglo-Swedish drugmaker AstraZeneca has sold US right for its Synagis infant respiratory drug to Swedish Orphan Biovitrum (Sobi) for an upfront sum of $1.5 billion. The payment consists of $1 billion in cash and $500 million in Sobi ordinary shares, equivalent to a stake in the Swedish company of 8%.

The sale is part of AstraZeneca’s moves to refocus its portfolio and follows the divestment earlier this month of rights outside the US for several respiratory drugs to Switzerland’s Covis Pharma.

“We continue to streamline our portfolio, allowing AstraZeneca to allocate resources more effectively, while Sobi’s focus on Synagis will enable infants in the US to continue benefiting from this important treatment,” said AstraZeneca’s CEO, Pascal Soriot.

Sobi’s president and CEO, Guido Oelkers, added that the addition of Synagis “will become an important catalyst for Sobi’s future development and will form a powerful platform for growth in rare diseases.”

About 130 AstraZeneca staff will transfer to Sobi, which also gains the right to participate in AstraZeneca’s share of US profits and losses related to MEDI8897, a vaccine for immunizing infants against respiratory syncytial virus (RSV) that received US Fast Track Designation in March 2015. AstraZeneca is developing and commercializing MEDI8897 with Sanofi Pasteur.

Under the terms of the deal, AstraZeneca is also eligible to receive up to $470 million in sales-related payments for Synagis; a $175-million milestone following the submission of the Biologics License Application for MEDI8897; potential net payments of around $110 million on achieving other profit and development milestones for MEDI8897 and a total of $60 million in non-contingent payments for MEDI8897 during the period 2019-2021.

The sale is expected to complete very early in 2019, subject to the usual conditions.

In the year to Dec. 31 2017, pre-tax profits attributable to Synagis in the US were approximately $118 million.