Peplin cheered by sunspot trial results

Shares in Peplin Biotech (ASX:PEP) jumped today when the company announced that full analysis of the data from its Phase I safety and tolerability trial had provided "hugely exciting" results: in 40 per cent of cases, a single application of its PEP005 topical gel for pre-cancerous skin 'sunspots' completely or substantially cleared the volunteers' actinic keratoses (AK), compared with 15 per cent for placebo patients.

The double-blind, placebo-controlled trial was conducted in the US, recruiting 14 men and two women aged between 42 and 82 with multiple AK lesions. From these, 11 received the treatment, and five control subjects were treated just with the carrier gel.

One patient's five AK lesions cleared completely within 21 days of the single, low-dose application of PEP005 at a 0.01 per cent concentration in the gel medium. In another patient, four of five lesions disappeared.

As Peplin reported in November, the trial confirmed that the drug was well tolerated, causing predicted mild local inflammation that rapidly resolved, with no other adverse of systemic effects.

MD and CEO Dr Michael Aldridge pointed out that the drug works, in part, by eliciting a local inflammatory reaction that brings neutrophils to the site of the lesion. These are thought to mop up any pre-cancerous cells that evade the drug's primary, cell-killing activity.

In the PEP005 treatment group, the lesions began to resolve around 14 days after the single application. Aldridge said this contrasted with the many weeks to months required for current market-leading treatments for AK lesions, which must be applied daily.

"These results are hugely exciting," he said. "Not only did the trial's results document the drug's favourable safety profile, they also showed that a single, low dose application of PEP005 Topical is able to resolve lesions in less than three weeks.

"Anyone who has used currently available topical products or been subjected to surgical approaches will appreciate the benefit of a short course of therapy and rapid clearance of lesions."

Aldridge said the results validated Peplin's decision in November, based on its preliminary results, to take back the drug from its former US collaborator, Allergan. Allergan had earlier paid Peplin over approximately US$6 million for the right to develop PEP005 as a topical treatment for squamous-cell and basal-cell carcinomas, the two most common forms of skin cancer.

Prospective partners

Aldridge was in San Francisco yesterday where he is having discussions with a number of potential partners, who have been showing keen interest since Allergan's withdrawal. He said the new results would strengthen the company's hand in negotiations to take the drug to market.

Peplin will fund the Phase II trials dose-ranging and efficacy trials from its own resources, giving it maximum leverage when it negotiates with partners.

The trials will be run entirely in Australia, and Peplin has already lined up clinical collaborators.

The company's detailed seven-page announcement was prompted in part by the ASX's severe criticism of WA biotech Solbec Pharmaceuticals last year for providing inadequate information to investors to judge the results of an animal trial of its anti-cancer compound SBT002.

At time of writing Peplin shares were up 19 per cent to $0.50.