Amrad and Merck select lead antibody for asthma

Melbourne-based Amrad (ASX:AML) and research partner Merck & Co have selected a lead therapeutic antibody for full preclinical development as a potential treatment for asthma and other types of respiratory disease.

The antibody targets a subunit of the interleukin 13 (IL-13) receptor over which Amrad holds patents, including one recently granted in the US.

Amrad partnered its IL-13 receptor antibody project with Merck in June 2003 in a deal potentially worth US$112 million, plus royalties on product sales.

"We've been working towards that with [Merck] now for about the last 18 months or so, to select the best antibody out of a pool of antibodies that we had to take forward into preclinical studies and into the clinic hopefully," said Amrad's newly appointed CEO Andrew Nash.

"Finally we've got to the point where we've agreed the antibody to move forward with."

While there is no specific milestone payment attached to the selection of the lead antibody, Amrad has already received payments totalling $US14 million, including an upfront payment of $5 million. The other $9 million stems from three milestone payments related to transferring technology to Merck, characterising the right antibodies and moving into preclinical studies, said Nash.

Further preclinical milestones payments are expected to flow to Amrad within this financial year as Merck progresses the lead antibody.

Nash said that for an antibody at this stage of development, phase I clinical trials are typically about 12 to 18 months away.

Studies in animal models have shown that IL-13 has a role in the mediation of inflammation associated with asthma. The IL-13Ra1 subunit targeted by the therapeutic monoclonal antibodies being developed by Amrad and Merck was discovered at the Walter and Eliza Hall Institute of Medical Research through a collaborative program conducted as part of the Cooperative Research Centre for Cellular Growth Factors, for which Amrad was the sole commercial partner.

Amrad is also collaborating with Cambridge Antibody Technology to develop antibodies against the GM-CSF receptor as potential therapeutics for rheumatoid arthritis and asthma.

"That also has a lead candidate antibody now that's in safety manufacturing preclinical studies. Those two programs are running neck and neck towards the clinic, and hopefully we'll have both of them in the clinic at around the same time," said Nash.