SOURCE: Antisense


October 13, 2009 12:05 ET

Antisense Therapeutics Announces ATL1103 on Track to Move Into Clinical Development

MELBOURNE, AUSTRALIA--(Marketwire - October 13, 2009) - Antisense Therapeutics Limited (PINKSHEETS: ATHJY) (ASX: ANP)

--  ATL1103: Antisense drug that targets the growth hormone receptor is
    set to become ANP's next drug to move into clinical development
--  Key animal toxicology studies on ATL1103 completed
--  Toxicology outcomes to date support plans for continued development
--  Technology partner ISIS to complete the manufacture of compound for
    initial clinical trial
--  ISIS to increase shareholding in ANP through the issue of new shares

Antisense Therapeutics Limited (PINKSHEETS: ATHJY) (ASX: ANP) is pleased to announce that the Company has now completed repeat-dosing toxicology studies for ATL1103 in two species -- mouse and non-human primate. Draft study reports from the study contractors in the United States have been received, and the toxicology outcomes from these studies support ANP's plans for the continued development of ATL1103.

ATL1103 is a second-generation antisense drug that targets the growth hormone receptor (GHR). By blocking the action of GHR, ATL1103 inhibits production of insulin-like growth factor -1 (IGF-I) from the liver thereby reducing its levels in the blood. GHR is a clinically validated therapeutic target in the growth disorder acromegaly (excessive growth of parts of the body and organs including the liver, kidney and heart) where the goal of treatment is to normalise IGF-1 levels in the blood. There is a clear need for better treatments for this niche and difficult to treat disease with the size of this market nearing US$1Billion per annum in drug sales.

In addition, treatments that reduce IGF-I levels in the blood (e.g. irradiation of the pituitary gland), have shown clinical benefit in the treatment of the disease diabetic retinopathy, a complication associated with diabetes where new blood vessels are formed in the eye with the potential to cause blindness. There is presently no pharmaceutical therapeutic approved for the treatment of vision impairment in the advanced stage of diabetic retinopathy. Consequently an effective treatment for this disease could secure a major position in this potentially multi-billion dollar market.

In animal study results previously reported by the Company, ATL1103 demonstrated its intended therapeutic action by significantly reducing IGF-I levels in the blood. ATL1103 has also demonstrated its intended therapeutic action in an animal model of retinopathy by significantly reducing retinal neovascularisation (formation of new blood vessels).

The repeat toxicology dosing studies in two species over several months are the major component of the ATL1103 toxicology program. The Company anticipates that the two remaining short term or acute studies, referred to as Safety Pharmacology and Genotoxicity, are to be completed by end of this year, after which it intends to be in a position to submit an application for a human clinical trial in the first half of 2010.

ANP's existing major shareholder and technology partner, Isis Pharmaceuticals Inc are now to complete the characterisation and release of the cGMP drug substance for formulation of the clinical supplies to be used in the planned future clinical trial. Isis will also prepare the drug substance CMC (Chemistry, Manufacturing and Controls) documentation for inclusion in the clinical trial application. Isis are undertaking this additional work in return for 18.475 million new ordinary shares in ANP. These shares will be placed in escrow for twelve months.

"We are very pleased to see another one of our satellite company partners progress another antisense drug towards the clinic," said C. Frank Bennett, Senior Vice President of Research of Isis Pharmaceuticals. "In ANP's case, this follows their lead compound ATL1102 which demonstrated successful Phase II results in patients with relapsing remitting MS. Similarly we are excited about the potential of ATL1103 to treat and improve the quality of life in patients suffering from difficult to treat diseases."

Background Information

ATL1103 is a second generation antisense drug designed to block growth hormone receptor (GHr) expression thereby reducing levels of the hormone insulin-like growth factor-I (IGF-I) in the blood and is a potential treatment for diseases associated with excessive growth hormone action. These diseases include acromegaly, an abnormal growth disorder of organs, face, hands and feet, and diabetic retinopathy, a common disease of the eye and a major cause of blindness. Acromegalic patients are known to have significantly higher blood IGF-I levels than healthy individuals. Reduction of these levels to normal is accepted by clinical authorities as the primary marker of an effective drug treatment for the disease. GHr is a clinically validated target in the treatment of acromegaly. In the case of diabetic retinopathy, published clinical studies have shown that treatments producing a reduction in IGF-I levels retarded the progression of the disease and improve vision in patients. ANP have published scientific papers demonstrating suppression of blood IGF-I levels in the mouse and inhibition of retinopathy in a mouse retinopathy model using an antisense drug to the GHr (Wilkinson-Berka et al., 2007, Molecular Vision 13, 1529-38; Tachas et al., 2006, J Endocrinol 189, 147-54) and ANP have previously reported that ATL1103 injection suppressed circulating levels of IGF-I in primates. ATL1103 commercialisation is covered by patent applications to at least 2023, and the potential for extensions to 2029 in some countries.

Acromegaly is a serious chronic life shortening disease triggered by excess secretion of growth hormone (GH) by benign pituitary tumours. Oversupply of GH over stimulates liver, fat and kidney cells, through their GH receptors, to produce excess levels of Insulin-Like Growth Factor-I (IGF-I) in the blood manifesting in abnormal growth of the face, hands and feet, and enlargement of body organs including liver, kidney and heart. The primary treatments for acromegaly are to surgically remove the pituitary gland and/or drug therapy to normalize GH and serum IGF-I levels. In North America, Europe and Japan there are approximately 40,000 diagnosed acromegaly patients with about half requiring drug therapy. In 2006, the total acromegaly market was valued at US$850M and forecast to grow with the introduction of newer and more effective medications.

Diabetic retinopathy is one of the leading causes of vision loss. Over 5 million Americans aged 18 and older are affected by diabetic retinopathy. Around 12,000-24,000 patients with diabetic retinopathy lose their eyesight each year in the US alone. This condition is caused by new blood vessel formation in the retina or macula (the central part of the retina). In diabetes, high blood glucose can cause oxygen deprivation in certain tissues, which can stimulate factors that induce additional blood vessels in the retina. These new blood vessels may break and bleed into the eye leading to scarring within the eye. Surgical ablative treatments such as photocoagulation (laser therapy) are available but are not completely effective, may cause partial vision loss, and can only be used a limited number of times. There is presently no pharmaceutical therapeutic approved for the treatment of vision impairment in the advanced stage of diabetic retinopathy.

Antisense Therapeutics Limited (ASX: ANP) is an Australian publicly listed biopharmaceutical drug discovery and development company. Its mission is to create, develop and commercialise antisense pharmaceuticals for large unmet markets. ANP has two drugs in development and two drugs in pre-clinical research. ATL1102 (injection) is in the advanced stages of a Phase IIa trial as a potential treatment of multiple sclerosis. ATL1103 is a second-generation antisense drug designed to lower blood IGF-I levels and is entering preclinical development as a potential treatment for acromegaly and vision disorders. ATL1102 (inhaled) is at the pre-clinical research stage as a potential treatment for asthma. ATL1101 is a second-generation antisense drug at the pre-clinical research stage being investigated as a potential treatment for prostate cancer. ATL1102 has been licensed to Teva Pharmaceutical Industries Ltd.

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