BioWorld International Correspondent

SYDNEY, Australia - After seeing results from a Phase II trial of a lead molecule being developed by Prana Biotechnology in Melbourne, a group of institutional and professional investors in the U.S. invested $20 million in the company.

The share placement by the group, led by OrbiMed Advisors and Xmark Funds, will be used by Prana to develop a second-generation version of that lead molecule through a separate set of Phase I and II trials.

Prana Executive Chairman Geoffrey Kempler said the investors became interested in the original molecule, called PBT-1, after seeing the results of a Phase IIa trial involving 36 patients published in the December issue of the journal Archives of Neurology.

He said the second-generation version, PBT-2, will undergo a series of Phase I trials starting later this year, and then proceed to Phase II.

PBT-1 and PBT-2 are metal protein-attenuating compounds, or MPACs, which have been shown to attack the amyloid plaques and bind the associated zinc and copper molecules in the brains of transgenic mice used as a model of Alzheimer's disease.

Colin Masters, a director of Prana and chairman of the company's scientific advisory board, presented the results of the extended Phase II trial of PBT-1 at the 8th International Springfield/Montreal Symposium on Advances in Alzheimer's Disease in Montreal last month.

Masters reported that the use of PBT-1 for 18 months "markedly slowed" the decline in cognitive function associated with Alzheimer's disease, compared with the predicted level of decline available from scientific literature.

The capital injection involved buying 4 million American depositary receipts at $5 each, with Rodman & Renshaw LLC acting as the placement agent for the offering. The investors also have bought warrants that will permit them to invest a further $24 million within three years.