Allergan and Molecular Partners have taken their partnership up a notch with two new deals to develop eye drugs worth up to just shy of $1.5 billion.

The companies have announced the significant expansion of their existing relations with two separate agreements centred on the discovery, development, and commercialisation of proprietary therapeutic DARPin-based products for the treatment of serious ophthalmic diseases. 

DARPins are a novel class of biological drugs that combine the high specificity, selectivity and safety of monoclonal antibodies with many advantages of small molecules, including high stability and low-cost production, according to private biotech Molecular Partners.

The company is heavily focused on the development of DARPins in the belief they could address significant unmet medical needs in large patient populations in various disease areas, and it seems Allergan - which itself is keen to beef up its ophthalmology portfolio - has also been convinced of their potential.

The first arrangement is an exclusive license deal focusing on the discovery, development, and commercialisation of an experimental DARPin known as MP0260 and its corresponding backups for the treatment of exudative age-related macular degeneration and related conditions. 

Working on MP0260

The companies will work together to develop MP0260 through human proof of concept, after which Molecular Partners could co-fund Allergan's development costs in exchange for a significant royalty slice.

The second is an exclusive discovery alliance under which the firms will put their heads together on the design and development of DARPins against selected targets implicated in causing serious diseases of the eye. 

In this instance, Allergan holds the right to exercise three options to exclusively license compounds for ophthalmology, for which it will be responsible for all subsequent development, manufacturing and commercialisation activities. And Molecular Partners stands to receive fees each time an option is taken up. 

Under the deals, Molecular Partners will get combined upfront payments of $62.5 million as well as up to $1.4 billion in development, regulatory and sales milestones, as well as tiered sales-based royalties up into the low double-digits.