Alnylam Pharmaceuticals, already considered one of the leading companies in the emerging field of RNA interference (RNAi), has merged with one of its rivals. The US firm has linked up with Germany's Ribopharma to create what it claims is a world leading company in the development of RNAi-based therapeutics.
The merger has created a new company called Alnylam Holding, and took place at the same time as a private round of fund-raising which raised $24.6 million (€21.5m). This brings its total paid-in capital to $43 million and ranks it "among the best-capitalised companies in the field," according to the merger statement. The first RNAi-based drug from the new entity is scheduled to start clinical trials later this year.
RNAi allows the inactivation of target genes by using complementary double stranded RNA (dsRNA) that binds to messenger RNA and prevents protein transcription. It is a naturally occurring defence against molecular parasites, discovered in 1998, and offers high specificity with a level of potency and stability that is far superior to that achievable with other technologies, such as antisense or ribozymes.
Despite its early promise, RNAi was initially limited to use in lower organisms such as Caenorrhabditis elegans and Drosophila, as dsRNA sequences tended to cause immune responses in mammalian cells. This was solved by the development of short sequences (siRNA), typically comprised of less than 30 base pairs, which can evade this immune response whilst effectively achieving gene silencing.
RNAi has emerged as a potent research tool for elucidating gene functions and validating drug targets. However, those properties that make siRNA sequences so useful in basic research, i.e. their potency, stability and specificity, also make them attractive as potential therapeutics.
Nevertheless, there are significant hurdles to overcome before siRNA-based therapeutics can enter the clinic. The primary obstacle is delivery. Mouse studies have shown that siRNA can be administered and achieve target gene silencing in vivo, although this requires near-continuous delivery or administration in very high volumes, which limits its clinical utility.
One potential solution is to use a vector to express the sequence in the patient. However, the safety problems encountered where vectors have been used in gene therapy suggest this present a different set of problems.
Alnylam has been give a kick start with the merger and fund-raising, but the RNAi sector is becoming increasingly competitive and the company will have its work cut out keeping ahead of the pack. One rival is Sirna Therapeutics, while a flurry of other companies including Cenix Bioscience, Ribozyme Pharmaceuticals, Cytrx, Intradigm and Cyclacel have recently unveiled ambitions in this area. Alnylam's position is that its strong intellectual property position in RNAi will be a key factor in persuading big pharma into partnership.
The company will have operating units in Kulmbach, Germany, and Cambridge, Massachusetts. Alnylam's chief executive (and former chief scientists at Millennium Pharmaceuticals) John Maraganore will serve as president and CEO of the new company, while Ribopharma CEO Roland Kreutzer will take up the position of chief operating officer. Stefan Limmer, chief science officer of Ribopharma, will act as chief technology officer of the new firm.