In less than six years, GlaxoSmithKline has moved from being “virtually nowhere” in biopharmaceuticals to becoming a player in this increasingly important area of drug development.

That is the view of Ian Tomlinson, senior vice president, biopharmaceuticals R&D at GSK. Speaking at a briefing in Stevanage UK, Dr Tomlinson said the recent launch of Arzerra (ofatumumab), which is partnered with Denmark’s Genmab for refractory chronic lymphocytic leukaemia, was just the beginning and that he had high hopes for many of the company’s biopharmaceuticals in late stage development.

The company was “a relatively late player in this field, but today 22% of GSK’s clinical portfolio are biopharmaceuticals and we are now making good progress in building and advancing the pipeline,” he said, adding that “our aspiration is to see 20% of the [biopharma] pipeline translate to 20% of launches by 2015”.

He was particularly excited about the prospects for GSK’s domain antibody (dAb) technology (dAbs are the smallest functional binding units of antibodies) which the company acquired with the 2006 purchase of Domantis. They have a molecular weight of around 11,000 compared with 150,000 for a conventional monoclonal antibody (mAb).

Dr Tomlinson noted that dAbs are thirteen times smaller than mAbs and “small is good, for example you can pack more molecules into an inhaler”. He added: “It also turns out that dAbs are very robust molecules; some can be boiled, cooled and still be functional – this makes formulation in dry powders and liquid formulation much easier”.

Steve Martin, business development unit head, dual targeting, noted that dAbs can also be ‘doubled-up’ to build a single antibody that simultaneously hits two targets. GSK sees great potential for these bi-specific dAbs in oncology and inflammatory diseases such as asthma; the company’s most advanced molecule is being developed to hit the cytokines IL-13 and IL-4, the ‘terrible twins’ of airway inflammation.

“We have made a lot of progress building the bispecific molecule. What is really exciting is that we are on the cusp of testing industrial scale manufacturing. If all goes well, we hope to start clinical trials sometime next year,” said Dr Martin. He concluded by saying that “the opportunity is there to go beyond what can be done with one antibody and deliver something that is a real step-change”.