Queensland Institute of Medical Research And Peplin Inc.: Scientific Peers Validate PEP005 Research

Brisbane, Australia, 15 April, 2004: The Queensland Institute of Medical Research (QIMR) and Peplin Biotech Ltd. (Peplin, ASX:PEP), today announced that five years of collaborative research on Peplin's new cancer drug, PEP005, had been published in the prestigious peer reviewed international journal Cancer Research.

Peplin Executive Director, Research Dr Jim Aylward said publication of the research paper in such a highly respected journal was an enormous validation by international peers of the quality of the science behind PEP005.

"While we are moving forward aggressively to commercialise PEP005 for skin cancer with our US partner Allergan, it is gratifying to receive such respected recognition." said Dr Aylward, who is a co-author of the paper.

"It is also instructive to appreciate the wide range of other cancers that this molecule may be effective in treating."

The article illustrates that three daily topical applications of PEP005 onto the skin above the tumour resulted in complete clearance of tumour in a panel of aggressive mouse and human tumours growing subcutaneously in mice. These tumours include melanoma and squamous cell carcinoma (both skin cancers) and lung, cervical and prostate cancers. Importantly, after a few weeks the skin over the previously existing tumour is almost normal, without significant scarring or loss of flexibility. The article also highlighted that PEP005 as a topical agent has a new cancer killing mechanism, which is different from the way that current cancer chemotherapy kills cancer cells. PEP005 induces primary necrotic cell death rather than the apoptotic cell death that is caused by current chemotherapeutic agents. The article notes that many cancers develop resistance to the apoptotic death mechanism of conventional chemotherapy, but this resistance is unlikely to present a problem for PEP005 topical treatment because this drug kills cells by a completely different mechanism. QIMR Director, Professor Michael Good said the article was testimony to Queensland's world class research climate.

"QIMR has been intimately involved in the development of Queensland intellectual property. It is rewarding to see the quality of Queensland research affirmed by our international peers, and also to see it move forward towards commercial reality," said Professor Good.

Minister for State Development and Innovation Mr. Tony McGrady said the article demonstrated that the Queensland Government's significant investment in biotechnology was paying off.

"We are seeing a lot of exciting research, but more importantly results, coming out of Queensland laboratories such as QIMR," Mr McGrady said.

"This new cancer treatment is certainly a great result for the many people afflicted by skin cancer throughout the state and indeed the world. I wish to congratulate the scientists for their excellent achievement."

Mr McGrady said that his background in Mount Isa in the state's far North West gave him an intimate understanding of the ravages skin cancer could cause and that this research meant hope to many sufferers.

ABOUT PEPLIN BIOTECH

Peplin Biotech Ltd is focused on the discovery, development and commercialisation of prescription human therapeutic products for the treatment of cancer and other diseases which have limited therapeutic options. Peplin's strategy is to leverage its pipeline of novel proprietary products through collaborative development arrangements with international pharmaceutical companies. Peplin's lead product is a potential topical therapy for actinic keratosis and non-melanoma skin cancer. It is the subject of a joint development agreement with Allergan, Inc. of Irvine, California for commercialisation in North and South America.

Peplin's earlier stage pipeline is targeted at other forms of cancer using intralesional and systemic routes of administration. Its new portfolio of EPUFA compounds opens additional potential opportunities in cancer and adds candidates for cardiovascular disease, pain, inflammation and diabetic complications.

Further information:

Michael Aldridge

Managing Director & CEO

Peplin Biotech Ltd

Tel: 07-3854-0980

michael.aldridge@peplin.com

Media enquiries:

Anita Westerberg-Jaensch

PhillipsGroup

Tel: 07-3230 5000

awesterberg-jaensch@phillipsgroup.com.au