Novartis has agreed to sell its blood transfusion diagnostics unit to Spain's Grifols for $1.68 billion, the first of what many believe will be a number of sell-offs at the Swiss major.

Acquired in 2006, the unit is dedicated to "increasing transfusion safety worldwide with nucleic acid testing, blood testing products and immunoassay reagents that detect infectious disease", Novartis notes. It is headquartered in Emeryville, California, and posted sales last year of $565 million.

Novartis stressed that its companion diagnostics unit and the Genoptix business are not included in the sale as they are closely linked to its pharmaceuticals operations. Chief executive Joseph Jimenez added that the sale "enables us to focus more sharply on our strategic businesses".

However, quite what constitutes a strategic business for Novartis is under the microscope at the moment. The sale to Grifols, the world's third largest producer of plasma-derived therapies, follows a group-wide review headed by new chairman Joerg Reinhardt.

Novartis is a market leader in three fields - pharmaceuticals, eyecare and generics - but is looking at what role three other divisions (vaccines and diagnostics, over-the-counter products and animal health) will have in the future.

Regarding the latter units, Mr Jimenez told Reuters that "we need to have global scale in these businesses and right now we're in that process of gaining scale or considering other options for these businesses". He added that "I wouldn't want to speculate on the outcome [as] our objective is to determine what it would take to gain global scale". If that is not possible, sell-offs "would be a potential outcome".

As for Grifols, the Barcelona-based group is financing the acquisition with a $1.5 billion loan from Nomura, BBVA and Morgan Stanley. The deal is expected to close in the first half of 2014.