In 1978, two NCI researchers published a report showing taxol was mildly effective in leukaemic mice. In November 1978, taxol was shown to be effective in xenograft studies. Meanwhile, taxol began to be well known in the cell biology, as well as the cancer community, with a publication in early 1979 by Susan B. Horwitz, a molecular pharmacologist at Albert Einstein College of Medicine, showing taxol had a previously unknown mechanism of action involving the stabilization of microtubules. Together with formulation problems, this increased interest from researchers meant that, by 1980, the NCI envisaged needing to collect of bark. Animal toxicology studies were complete by June 1982, and in November NCI applied for the IND necessary to begin clinical trials in humans.