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* AstraZeneca confirms talks with biotech firm Acerta
* Signals determination to build up cancer drug business
* "No certainty" that any deal will be agreed (Adds comment on other potential bidders for Acerta)
By Ben Hirschler
LONDON, Dec 14 (Reuters) - AstraZeneca said onMonday it was in talks that might lead to the acquisition ofprivately held biotech firm Acerta Pharma, a potential $5billion-plus deal designed to build up its cancer drugportfolio.
"AstraZeneca confirms that it is exploring potentialstrategic options with Acerta Pharma BV. There can be nocertainty that any transaction will ultimately be entered into,or as to the terms of any transaction," it said in a briefstatement.
Credit Suisse analysts said acalabrutinib's considerablepotential could also encourage other potential buyers. "IfAcerta is open to a transaction, we would expect significantinterest from multiple other bidders," they said in a note.
The Wall Street Journal had reported on Friday that theBritish drugmaker was looking to buy Acerta for more than $5billion to gain access to its experimental blood cancer drugacalabrutinib.
Acalabrutinib works in a similar way to Imbruvica, which wasdeveloped by Pharmacyclics but is now controlled by AbbVie after the U.S. drugmaker bought Pharmacyclics for $21billion earlier this year. Johnson & Johnson jointlymarkets Imbruvica.
Both drugs are so-called Burton's tyrosine kinase inhibitorsthat target an array of blood cancers and have the potential tobecome multibillion-dollar-a-year sellers, according to industryanalysts. They may also help in autoimmune diseases like lupus.
Given pharmaceutical companies' current heated interest inoncology, Bernstein analyst Tim Anderson said it was notsurprising that Acerta, based in California and the Netherlands,was an acquisition candidate.
PIPELINE BOOST
Acerta does not yet have a partner to help develop itsleading drug, although it has agreed to test acalabrutinib incombination with Merck's Keytruda.
Acerta is running a wide range of cancer clinical trials,including two final-stage Phase III studies. Last week itreported positive results in leukaemia.
The decision to chase after Acerta reflects a determinationby AstraZeneca Chief Executive Pascal Soriot to use deals toboost his company's pipeline as sales of older blockbusters,including cholesterol fighter Crestor, lose patent protection.
Last month he agreed to buy ZS Pharma, a specialistin treating high potassium levels, for $2.7 billion.
The biggest hopes are pinned on oncology, however, whereAstraZeneca already has a goal of bringing six new cancertreatments to market by 2020.
Its new lung cancer pill Tagrisso, which it believes couldsell $3 billion a year, was approved last month and the companyalso recently launched Lynparza for ovarian cancer.
Buying Acerta would take AstraZeneca into the less familiarterritory of blood cancers and some analysts said the movesuggested a bigger commitment to this area of oncology thaninitially expected.
Earlier this year AstraZeneca signed a deal to co-developanother cancer drug, durvalumab, in blood cancers with Celgene because it said at the time it had limited experiencein the field. (Editing by Mark Potter and Keith Weir)
