An influenza pandemic is a global outbreak of disease that occurs when a new flu virus appears in the human population, causes serious illness, and spreads easily from person to person.
Over the last several years, a highly virulent new strain of avian flu (H5N1) has become endemic in the poultry population in Southeast Asia, has spread to parts of Europe and Africa, and has caused significant mortality in humans that have been infected.
The World Health Organization (WHO) and Centers for Disease Control and Prevention (CDC) have expressed major concern about the potential for this virus to mutate into a form that could cause a global pandemic of human disease.
Under the terms of the agreement, Alnylam and Novartis will advance RNAi therapeutics for pandemic flu to initial clinical testing and, if successful, regulatory approval. Financial terms were not disclosed.
This collaboration is in addition to the collaboration formed by the two companies in September 2005, and reinforces the development program for pandemic flu announced by Alnylam in December 2005.
"The influenza virus, through rapid mutation and potential inter-species transfer, represents an epidemic threat to the citizens of all countries. Multiple therapies are likely to be required both to prevent and to treat influenza," said Mark Fishman, president of the Novartis Institutes for BioMedical Research.
"An RNAi therapeutic could be an innovative modality, crippling the virus through incapacitating several genes. In addition, such drugs might be adapted to new strains as they emerge. Of course, the technology is young and is just now being tested in early clinical trials, but our hope is that it will open new therapeutic frontiers," he added.
RNA interference, or RNAi, is a naturally occurring mechanism within cells for selectively silencing and regulating specific genes.
Since many diseases are caused by the inappropriate activity of specific genes, the ability to silence genes selectively through RNAi could provide a new way to treat a wide range of human diseases.
RNAi is induced by small, double-stranded RNA molecules and one method to activate RNAi is with chemically synthesised small interfering RNAs, or siRNAs, which are double-stranded RNAs that are targeted to a specific disease-associated gene. The siRNA molecules are used by the natural RNAi machinery in cells to cause highly targeted gene silencing.
In December 2005, Alnylam announced that it had selected its pandemic flu program as a development program.
The company also announced that it had received initial government funding for the program from the Department of Defense's 'Defense Advanced Research Projects Agency' (DARPA).
The focus of the program is the development of an RNAi therapeutic targeting sequences both specific for particular strains and conserved across all flu strains, including those of avian origin.
This RNAi therapeutic would be expected to have anti-viral activity against any newly emerging strain of influenza capable of causing human disease and leading to a pandemic, including any variant of the H5N1 strain.