* British firm sells non-core antibiotics unit to Pfizer
* Says deal fits strategy of focusing on cancer and otherareas
* Pfizer will pay $550 mln on completion and $175 mln in2019
* Will also pay sales-related payments and royalties (Adds details, shares)
LONDON, Aug 24 (Reuters) - Pharmaceutical companyAstraZeneca has agreed to sell its small moleculeantibiotics business to Pfizer Inc in a deal that couldbe valued at more than $1.5 billion.
AstraZeneca, which saw off a $120 billion takeover attemptby Pfizer in 2014, said the sale would allow it to focus ondeveloping new medicines in its main areas of cancer, andrespiratory and cardiovascular diseases.
The U.S. company, which on Monday bought cancer drug firmMedivation for $14 billion in cash, said the antibiotics wouldenhance its portfolio of more than 60 anti-infective andanti-fungal medicines.
The medicines include approved antibiotics Merrem, Zinforoand Zavicefta, and ATM-AVI and CXL, which are in clinicaldevelopment, AstraZeneca said.
Pfizer will pay $550 million upon completion and a furtherunconditional $175 million in January 2019, AstraZeneca said.
It will also pay up to $250 million in milestone fees, up to$600 million in sales-related payments and recurring,double-digit royalties on future sales of Zavicefta and ATM-AVIin certain markets.
The two established medicines in the deal --- Merrem, usedto treat serious infections in hospitalised patients, andZinforo, an intravenous antibiotic used for skin and soft tissueinfections and pneumonia -- generated sales of $250 million in2015, AstraZeneca said.
The British company said the agreement did not impact itsfinancial guidance for 2016.
Its shares were trading down 0.2 percent in early deals onWednesday, broadly in line with the market.
(Reporting by Paul Sandle; editing by Kate Holton/Keith Weir)