Four of the best: pSiVida, Progen, AustCancer, Anadis

Three Australian biotechnology companies logged share price gains of over 300 per cent this financial year: pSivida (ASX: PSD) soared 387 per cent, Progen (ASX:PGL) was up 368 per cent and Australian Cancer Technology (ASX:ACU) was up 316 per cent. Biopharmaceutical company Anadis (ASX:ANX) also hit its stride, its share price rising 177 per cent.

Perth-based pSiVida describes itself as a nanotechnology company, but is developing biomedical and veterinary applications for its proprietary biocompatible, biodegradable, nanoporous silicon material, BioSilicon. The company is also exploring strategic defence applications for BioSilicon nanotechnology devices.

BioSilicon is a promising substrate for bradytherapeutics: slow, or sustained release therapeutics to treat a wide range of diseases, including metabolic disorders, and cancer.

Fine particles of BioSilicon are “doped” with the phosphorus radisotope 32P. Injected into tumours, BrachySil delivers sustained, short-range radiation over several weeks to kill cancerous cells. Singapore General Hospital oncologists are currently running a phase IIb clinical trial of pSiVida’s BrachySil™ in liver-cancer patients.

In nanoporous form, BioSilicon can be charged with therapeutic drugs and implanted in the body to release them as it biodegrades. Proteins can be attached to the surface of BioSilicon “chips” to create implantable diagnostic or metabolism-monitoring devices

PSiVida is also eveloping tissue-engineering and prosthetic applications BioSilicon.

The company was granted a number of patents on new Biosilicon applications during the year. In June it announced it had acquired 100 per cent ownership of its UK subsidiary pSiMedica, as a prelude to listing on the NASDAQ next year.

Avastin boost for Progen

Brisbane-based cancer-drug developer Progen has reported promising – even spectacular - results from clinical trials of its angiogenesis-inhibitor, PI-88.

In January the company announced it had begun a new, multi-centre phase I/II clinical trial of PI-88 in patients with malignant melanoma, one of the most aggressive and lethal of all cancers.

In late 2003, the University of Colorado Health Sciences Centre (CHSC) in Denver, one of the leading centres for testing new cancer drugs, completed a dose-ranging trial in 42 patients with advanced secondary melanoma tumours. Metastatic melanoma is normally rapidly lethal, but at the time the new trial was announced in January, 17 of the 42 patients treated with PI-88 were still alive – the first patient treated was still alive 30 months after he received his first dose. One doctor involved in the trial described the result as “unprecedented”.

Progen’s shares surged last year when US investors moved in after an announcement by US Biotech giant Genentech that its own candidate angiogenesis inhibitor, Avastin, had successfully completed a Phase III trial in colon-cancer patients. It surged again in February when the US Food and Drug Administration approved Avastin’s clinical use.

Like Avastin, PI-88 inhibits the growth of new blood vessels that keep rapidly growing tumours supplied with oxygen and nutrients; because this process, called angiogenesis, is common to all solid tumours, PI-88’s therapeutic potential extends to a wide range of cancer types.

AustCancer forges ahead

Australian Cancer Technology is conducting a Phase II trial of a novel anti-cancer vaccine, Pentrys, developed by award-winning oncologist Dr Robin Ward, of Sydney’s St Vincent’s Hospital.

The Pentrys vaccine – the name means “53” – primes the immune system to attack cells displaying mutant forms of a tumour-suppressor protein called P53 on their surface. The P53 protein is a key mediator of programmed cell death, or apoptosis – normally, it instructs cells carrying a high mutation load to commit “suicide”. But when P53 is itself silenced by mutation, the cell is free to grow out of control.

P53 normally functions in the cell nucleus, away from the immune system’s gaze. But when it is mutant, it ends up on the cell’s outer surface.

Because the loss of P53 is typically the last event that tips a cell into cancerous growth, any cell displaying mutant P53 proteins on its surface is, by default, cancerous.

About 60 per cent of all cancers display mutant P53 proteins, including many common cancers. If the Pentrys vaccine works, it should have generic activity against a wide range of cancers.

AustCancer has another promising anti-cancer drug in its kinase inhibitor Chk1 – kinase inhibitors work by jamming the cell-division machinery of fast-dividing cancer cells.

The market also looked favourably on AustCancer’s appointment last year of experienced executive Paul Hopper as its CEO last year.

Hopper was responsible for AustCancer’s recent takeover last month of Alabama-based Galenica, whose vaccine-boster GP-0100 has just gone into Phase 2 clinical trials at leading cancer research institute, New York's Memorial Sloan Kettering Cancer Centre last month.

Anadis: milk and nutraceuticals

Melbourne biopharmaceutical company Anadis has an unusual product portfolio, based on extracts of bovine colostrum, the antibody-rich “first milk” of dairy cows.

The pregnant cows are immunised with antigens from pathogenic human bacteria and viruses, such as strains of E. coli bacteria that cause traveller’s diarrhoea. The cows respond by making antibodies, which appear in their colostrum when their calves are born.

Anadis recently signed an agreement with its partner, Tatura Milk Industries, securing its colostrum supply from Tatura’s large herd of hyperimmunised dairy cows.

It is also about to launch its traveller’s diarrhoea product, Travelan, which contains antibodies to 14 pathogenic strains of E. coli bacteria found in water supplies around the world.

Anadis is also preparing to launch an over-the-counter nutraceutical, Pyloran, which has been shown to reduce gastritis and gastric ulcers caused by chronic Helicobacter pylori infection of the stomach.

In May, Anadis announced its first sale to China – a 3-tonne shipment of a bovine-colostrum “nutraceutical” that will be used as a health food by the Chinese military, to provide protection against enteric bacteria.

Anadis has also been involved in talks with the Taiwan Government, which is interested in the company’s trials of a colostrum extract containing antibodies to an enterovirus, known as Enterovirus 71, which causes a polio-like paralytic disorder called hand, foot and mouth disease in children.

A recent outbreak of hand, foot and mouth disease affected 4.5 million Taiwanese children; many will suffer chronic health effects including slack facial muscles, and limb weakness.

The US Military has shown interest in a colostrum extract that could protect soldiers who may be exposed to biowarfare microbes like anthrax bacteria and the bubonic plague virus. In February the commonwealth government gave Anadis an Innovation Access Program grant of AUD$786,500 towards the company’s respiratory pathogen program.