( human use. The experimental work rep...)Calando Pharmaceuticals Publishes the First Non-Human Primate Study,on Targeted, Systemic Delivery of siRNA in National Academy of,Sciences Journal,Health

"The experimental work reported in this paper shows that CALAA-01 can safely be repeatedly administered to large animals," said Jeremy Heidel, Calando's Chief Scientific Officer. "We observed a lack of significant immunostimulation and, notably, the absence of complement activation, even at the highest dose administered. The results of this study are promising and suggest further investigation of CALAA-01 is warranted."

"These results demonstrate that our lead siRNA formulation CALAA-01is well tolerated at levels many times higher than what we would expect to be an efficacious dose in humans," said John Petrovich, Calando's Chief Executive Officer. "We are proceeding with full IND-enabling toxicology studies as the next step toward commencing what we believe will be the first Phase I clinical trial with a targeted, systemic formulation of siRNA by the end of 2007."

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About RNA Interference (RNAi)

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. One method to activate RNAi is with chemically synthesized 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 c
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