Prana Announces Success in Phase IIa Clinical Trial of PBT2 in Early Alzheimer's Disease PBT2 demonstrates positive biomarker and cognitive effects

Announces Success in Phase IIa Clinical Trial of PBT2 in Early Alzheimer's

demonstrates positive biomarker and cognitive effects

Australia - February 26, 2008: Prana Biotechnology Limited (NASDAQ: PRAN /

biopharmaceutical company focused on the research and development of treatments

for neurodegenerative disorders, today announced that PBT2 has demonstrated

safety and tolerability and reduced Abeta 42, in a Phase IIa study of PBT2

patients with early Alzheimer's Disease. PBT2 also improved Executive Function

performance in select cognitive tests.

a very exciting and important milestone for the company, particularly because

PBT2, a drug known to inhibit the toxic oligomers of Abeta that cause the

functional damage in Alzheimer's Disease, was able to show such a clear effect

in a short trial," commented Geoffrey Kempler, Prana's Chairman and CEO.

double blind multi-centre clinical trial, 78 patients in Sweden and Australia

were randomized to receive either a placebo, PBT2 50mg or PBT2 250mg capsule

once per day for 12 weeks.

of the trial data demonstrated that the safety and tolerability profile of

at both doses was indistinguishable from that of placebo. There were no study

withdrawals related to adverse events. There was no serious adverse event (SAE)

in any PBT2 treated patient.

also demonstrated the impact of PBT2 on reducing Abeta 42 in the cerebrospinal

fluid (CSF) that surrounds the brain and spinal cord, considered a key biomarker

for Alzheimer's Disease. Specifically, PBT2 at the 250mg dose showed a highly

significant reduction in CSF Abeta 42 compared to placebo (p=0.006). The effect

of PBT2 was dose related (p=0.02).

Jeffrey Cummings, Director of the Easton Centre for Alzheimer's Disease at UCLA,

and Head of Prana's Research and Development Advisory Board, commented that

"PBT2 has hit what we consider to be the critical target for Alzheimer's

Disease, as evidenced by the significant reduction in Abeta 42."

signs of cognitive improvement, as measured by the Neuropsychological Test

Battery (NTB), were also observed. Statistically significant improvement was

evident in two of the four Executive Function NTB tests: the Category Fluency

Test (p=0.028) and the Trail Making Test part B (p=0.005), both after 12 weeks

of treatment at the 250mg dose compared to placebo. PBT2, in this study of

disease progression, had no effect on ADAS-cog, a test of cognition not designed

to measure Executive Function changes. The NTB is a test of cognition that

more sensitive to the changes in Executive Function that are seen in the early

stage of Alzheimer's Disease.

impact of this drug on Executive Function is very encouraging as this is likely

to predict an improvement in the day to day functioning in the lives of people

with Alzheimer's Disease. The ability to plan and execute everyday activities,

even more so than memory, offers great practical and clinical benefit to

patients" added Professor Cummings.

results build on earlier observations using PBT2 in transgenic mouse models

Alzheimer's Disease, where PBT2: reduced toxic oligomers of Abeta, reversed the

Abeta-induced loss of neurotransmission and improved cognition.

plans to further progress PBT2 into larger and longer clinical trials to

investigate its potential as a disease modifying drug.

very hopeful that PBT2 will continue to perform as well as it has in this trial

and progress through the development pathway, eventually to bring true benefit

to patients with Alzheimer's Disease. PBT2 is one of many Metal Protein

Attenuating Compounds (MPACs) within the Prana pipeline, which we are

enthusiastic to develop for a range of neurodegenerative diseases," concluded

refer to the Appendix below which is included in, and forms part of, this

company will hold a conference call to discuss the above results and welcomes

participation from interested parties.

from the US or Canada (toll-free)

from other locations

in at least 10 minutes prior to commencement to access

Prana or conference ID # 64631038

will be webcast and available on the Prana website www.pranabio.com

of the call will be available 2 hours later until 11.59pm (US eastern time)

888-286-8010 from the US or Canada (toll - free) or +1 617-801-6888 from other

locations.To enter conference dial ID # 16766828

Prana Biotechnology Limited

Biotechnology was established to commercialize research into Alzheimer's Disease

and other major age-related neurodegenerative disorders. The Company was

incorporated in 1997 and listed on the Australian Stock Exchange in March 2000

and listed on NASDAQ in September 2002. Researchers at prominent international

institutions including The University of Melbourne, The Mental Health Research

Institute (Melbourne) and Massachusetts General Hospital, a teaching hospital

Harvard Medical School, contributed to the discovery of Prana's technology.

further information, please visit the Company's web site at

press release contains "forward-looking statements" within the meaning of

section 27A of the Securities Act of 1933 and section 21E of the Securities

Exchange Act of 1934. The Company has tried to identify such forward-looking

statements by use of such words as "expects," "intends," "hopes," "anticipates,"

"believes," "could," "may," "evidences" and "estimates," and other similar

expressions, but these words are not the exclusive means of identifying such

statements. Such statements include, but are not limited to any statements

relating to the Company's drug development program, including, but not limited

to the initiation, progress and outcomes of clinical trials of the Company's

drug development program, including, but not limited to, PBT2, and any other

statements that are not historical facts. Such statements involve risks and

uncertainties, including, but not limited to, those risks and uncertainties

relating to the difficulties or delays in financing, development, testing,

regulatory approval, production and marketing of the Company's drug components,

including, but not limited to, PBT2, the ability of the Company to procure

additional future sources of financing, unexpected adverse side effects or

inadequate therapeutic efficacy of the Company's drug compounds, including,

not limited to, PBT2, that could slow or prevent products coming to market,

uncertainty of patent protection for the Company's intellectual property or

trade secrets, including, but not limited to, the intellectual property relating

to PBT2, and other risks detailed from time to time in the filings the Company

makes with Securities and Exchange Commission including its annual reports

From 20-F and its reports on Form 6-K. Such statements are based on management's

current expectations, but actual results may differ materially due to various

factions including those risks and uncertainties mentioned or referred to in

this press release. Accordingly, you should not rely on those forward-looking

statements as a prediction of actual future results.