Anticalins look promising

German biopharmaceutical company Pieris has completed studies of its proprietary candidate, PRS-060 Anticalin, which has been formulated into a microspray for treating the underlying mechanism for asthma. The studies so far have shown that the inhalable lead candidate had a 10 fold higher bioavailability than an inhalable antibody via intratracheal administration. "This important milestone demonstrates the exciting potential of Anticalin-based products for the treatment of respiratory disease,"​ Pieris director of science and preclinical development Dr Andreas Hohlbaum said. Anticalins are engineered from human lipocalins, which are a family of naturally binding proteins. While fundamentally similar to monoclonal antibodies in terms of binding properties, anticalins are much smaller in size, about 20kDa. They also have robust physiochemical properties and their simple composition allows for highly soluble and stable products to be easily manufactured from E. coli​. PRS-060 targets an undisclosed target which is involved in the origin of asthma. The mode of action is unique compared to currently available asthma treatments, meaning the product has development potential in treating patients whose disease is not well controlled through standard therapies. In the preliminary studies a liquid formulation was used in a microspray device. But Pieris senior manager of business development Birgit Zech told in-PharmaTechnologist.com that the formulation could be changed to either an inhalable powder or developed in an inhaler system as a liquid aerosol. While also having the potential to be formulated as an intravenous or subcutaneous administration, Zech said the ability to inhale the anticalin showed the product was robust and stable enough in this form, unlike antibodies. Pieris chief executive Evert Kueppers said in a statement: "This study confirms the ability of PRS-060 to be formulated in a way ideally suited to its application in asthma, namely as an inhalable preparation for home use." ​ With no anticalins on the market yet, this is a new area of biopharma discovery. It holds many advantages over monoclonal antibodies such as being independent of antibody intellectual property issues. The worldwide revenue from monoclonal antibodies exceeded $20bn in 2006 and is forecast to exceed $30bn in 2010. Pieris is now actively seeking licensing partners to help develop PRS-060.