Biota gets ready to inhale

Melbourne anti-viral drug developer Biota Holdings (ASX:BTA) has signed an agreement with American company Aerogen (NASDAQ:AEGN) to use Aerogen's Aeroneb nebuliser in clinical trials of new, long-acting anti-viral compounds for influenza developed by Biota and its Japanese partner Sankyo.

The US National Institutes of Health (NIH) has awarded a US$5.6 million grant to Biota and Sankyo that will fund development of an aerosol device to deliver their second-generation anti-viral compounds, called long-acting neuraminidase inhibitors (LANIs). The grant will also fully fund three Phase 1 clinical trials over the next three years.

Biota CEO Peter Molloy said today that the results of animal trials indicated that a single dose of the companies' lead compound, CS-8958, could provide protection against influenza, or suppress an established infection, for at least seven days.

Aerogen is leading developer of aerosol devices for delivering drugs for respiratory disorders, based on its OnQ Aerosol Generator.

Aerogen's chairman and CEO, Dr Jane Shaw, said that, with its efficiency and ease of use, her company's Aeroneb Go Nebuliser was "particularly suited" for delivery of LANIs in patients of all ages.

Molloy said the Biota-Sankyo project had produced four LANIs - CS-8958 was developed by Sankyo researchers, and Biota had three of its own compounds in reserve if it failed to fulfil its promise. Molloy said CS-8598 is "at least as active" as Biota's pioneering flu drug zanamavir (GlaxoSmithKline's Relenza).

He said the first step would be to develop a formulation to solubilise CS-8958 for delivery by the Aerogen nebuliser.

Biota and Sankyo are developing a dry-powder form of the drug for direct delivery into the lungs via an asthma- or Relenza-type inhaler.

The drug, which would be sold through prescription, would contain a one- or two-shot dose, for individual use.

However, the NIH grant will be used to develop a soluble form of the drug for aerosol delivery, as a front-line weapon to protect large numbers of people in key occupations - for example, medical personnel in hospitals - in the event of an influenza pandemic.

The drug would be stored as a dry powder for long periods, and reconstituted in liquid form in an emergency.

Molloy said it would probably take four to six months to develop a suitable medium to rapidly solubilise the powdered drug, which would be formulated to have a shelf life of at least six years.

The limited, three-year shelf life of GSK's Relenza, and rival Roche neuraminidsase inhibitor Tamiflu, has been problematic for both companies, forcing them to spend millions of dollars to buy back stockpiled supplies that have reached their expiry date.

The longer storage life of LANIs will meet the need of governments stockpiling anti-influenza drugs against the possibility of an influenza pandemic - but Molloy said, that with the imminent threat of a pandemic of H5Ni "bird flu" from Asia, it was unlikely that the new Biota-Sankyo LANI would be ready in time.