Alexion Pharmaceuticals is paying $100 million upfront as part of an agreement with Moderna Therapeutics to develop messenger RNA  treatments for rare diseases.

Alexion, which has also made a $25 million equity investment into Moderna, has purchased ten product options to the latter's mRNA therapeutics platform. Moderna will also be entitled to commercial and drug development milestone payments, as well as high single- to double-digit royalties.

The partners say that mRNA therapeutics are designed to use the body’s natural processes to enable the in vivo production of both intracellular proteins, which remain within the cells, and secreted proteins, which are released into the bloodstream and act to restore function elsewhere in the body. As a result, they have the potential "to speed the development and manufacture of treatments for many rare diseases that are currently untreatable with existing technologies".

Alexion chief executive Leonard Bell said mRNA therapeutics represent "an especially exciting drug discovery platform, and we look forward to combining Moderna’s deep expertise in mRNA with Alexion’s significant global resources and expertise in drug discovery, clinical studies, regulatory affairs and commercialisation for the benefit of patients worldwide". His company markets Soliris (eculizumab), approved for paroxysmal nocturnal haemoglobinuria, an ultra-rare and life-threatening blood disorder, and atypical haemolytic uraemia syndrome.

His counterpart at Moderna, Stephane Bancel, said that "given the broad potential of this new drug modality, we wanted to forge a few long-term strategic relationships with best-in-class companies. As we were looking for a global leader with a proven track record in the discovery, development and global commercialisation of treatments for patients with rare diseases, entering into a strategic agreement with Alexion became an obvious choice for us".

In March last year, Moderna signed an mRNA therapeutics deal with AstraZeneca.