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By Ben Hirschler
LONDON, July 31 (Reuters) - AstraZeneca isaccelerating its push into cancer immunotherapy, with plans totest a key experimental drug in new tumour types.
The company is seen as No. 4 in a race to develop the firstdrug in a new class that fights cancer by unleashing the body'simmune system, behind rivals Roche, Merck & Co and Bristol-Myers Squibb.
But its MEDI4736 medicine is still viewed as a highlypromising agent, both on its own and in combination with othertreatments.
AstraZeneca said on Thursday it would launch a pivotalclinical trial programme with MEDI4736 in head and neck cancerthis year, in addition to ongoing tests in lung cancer, and wasalso looking at expanding tests into other cancer types.
"There is the potential we would announce an additionaltumour type beyond head and neck and non-small cell lung cancerby the end of this year," head of medicines development BriggsMorrison told analysts in a post-results conference call.
MEDI4736 is part of a closely watched class of drugs knownas anti-PD-L1 therapies, which block a tumour's ability to evadethe immune system's defences.
AstraZeneca said it would present further data looking atMEDI4736 in lung cancer, as well as early results for head andneck cancer, in September at the annual meeting of the EuropeanSociety for Medical Oncology.
Analysts said the decision to study MEDI4736 in head andneck cancer made sense, given encouraging results with a similarMerck drug for the condition reported in June.
The commercial promise of MEDI4736 was flagged byAstraZeneca during its recent $118 billion takeover battle withPfizer, when it argued that the drug - used on its ownand in combination with other therapies - could potentiallygenerate annual sales of $6.5 billion.
In recent years, the British drugmaker has become best knownfor its cholesterol drug Crestor and its ulcer and heartburnpill Nexium. But it has a long history in oncology, havingbroken new ground decades ago in developing tamoxifen and otherhormonal therapies. It also produced one of the first "targeted"cancer drugs, Iressa.
AstraZeneca earlier raised its sales and earnings forecastsfor 2014 after second-quarter sales and earnings both beatexpectations, helped by several one-off factors. (Editing by David Holmes)
