Roche could pay out more than $1 billion to Molecular Partners over the next few years under a research and licensing deal centred on the latter's DARPin-based route of drug delivery.

The Swiss drug giant is hoping that DARPins - non-antibody-based small proteins carrying a variable region has been engineered to bind to targets - will be able to carry the toxic agents it has developed straight to cancer cells leaving healthy tissues unharmed.

The small size and high binding affinity of DARPins enable them to hone in on and penetrate deep into solid tumours, which the companies believe makes them "ideal targeting agents to deliver toxic agents to tumours to kill cancer cells".

Because they bind to different epitopes than antibodies, and multiple targets in parallel at the same time, DARPins are believed to have a higher selectivity for tumour cells compared to other biologics including antibody drug conjugates, Roche noted, further explaining its interest in the deal.

"By combining [Roche's] technical and commercial expertise with our DARPin R&D expertise, we can rapidly develop a pipeline of highly differentiated products offering a novel approach to treating patients far more quickly than we could do independently, offering new hope for patients with unmet medical need," said Christian Zahnd, Molecular's chief executive.

The terms

Under the terms of the agreement, Roche rights gained rights to develop and commercialise several DARPin-based products. In return, Molecular stands to receive 55 million Swiss Francs upfront, but could potentially earn more than 1 million Swiss Francs if all development and sales milestones are met for all potential products, as well as double-digit tiered royalties on future sales.

The deal signifies growing interest and confidence in the DARPins; Molecular has already established alliances with Allergan and Johnson & Johnson unit Janssen, amongst others.