RNAi specialist Dicerna Pharmaceuticals Inc.'s chief operating officer, James Weissman, told BioWorld that scientists inside and outside of the company have come to believe in what's called "the X hypothesis" in hepatitis B virus (HBV). "My view, though, as a person who has been in the pharmaceutical industry for decades, is who cares, anyway?" he said as long as the drug works. He pointed out that, with the cholesterol therapy Lipitor (atorvastatin calcium) from New York-based Pfizer Inc., where he served in business development and marketing, "everybody had a different theory for why it lowered the incidence of heart disease. Nobody knew with certainty."