* Forecasts $45 billion sales by 2023 as new drugs deliver
* EPS growth expected to exceed revenue growth over 2017-23
* Biggest pipeline hopes hinge on new cancer drugs (Adds more drug details, latest shares, analyst and fund manager comments)
By Ben Hirschler
LONDON, May 6 (Reuters) - AstraZeneca Plc laid out its defence against Pfizer Inc's $106 billion takeover approach on Tuesday by predicting its revenues would rise 75 percent over the next decade, although only after a short-term drop.
With promising new medicines expected to lift annual sales above $45 billion by 2023, up from $25.7 billion in 2013, selling out to the U.S. group now would deprive investors of huge gains, it argued.
"The increasingly visible success of our independent strategy highlights the future prospects for our shareholders," said Chairman Leif Johansson. "These are benefits that should fully accrue to AstraZeneca's shareholders."
Investors and analysts agree Britain's second biggest drugmaker has an improving experimental drug portfolio in areas ranging from cancer to asthma, but they remain nervous about the uncertain commercial future of many products.
AstraZeneca has rebuffed three approaches from Pfizer, which wants to create the world's biggest pharmaceuticals company - and cut its tax bill - by buying the group. It said on Friday that the U.S. firm's latest offer of 50 pounds a share undervalued the company "substantially".
The British group has not ruled out a deal altogether, however, and people familiar with the matter said it was willing to talk if there were a compelling, higher offer.
Shares in AstraZeneca fell back 2.5 percent to 46.90 pounds by 1200 GMT.
While AstraZeneca faces declining revenue over the next three years as older medicines lose patent protection, the company forecasts "strong and consistent" growth from 2017 to 2023, driven by new treatments for cancer, diabetes, heart disease and lung disorders.
It also has a possible therapy for Alzheimer's disease, a notoriously difficult condition to tackle with medication.
Growth in core earnings per share, which excludes certain items, is expected to exceed revenue growth during this period, it added.
Jefferies analysts said the forecasts appeared "overly optimistic", although the detailed breakdown for products might help to push the price and cash mix in any deal higher. In addition to wanting a higher offer, AstraZeneca also says any viable deal must include a lot more cash than the 32 percent suggested by Pfizer, with the balance paid in shares.
AstraZeneca made the detailed forecasts for the next 10 years - an important salvo in its defence strategy - a day after Pfizer CEO Ian Read renewed his call for the British company's board to enter talks.
Read insisted his offer was "compelling" and signalled he was now looking at all options, including a possible hostile bid or looking at other targets, although he stressed that buying AstraZeneca remained "Plan A".
Most investor interest centres on AstraZeneca's experimental cancer medicines designed to boost the immune system. Such drugs promise to revolutionise treatment of many tumour types and would also complement Pfizer's line-up of oncology medicines.
But AstraZeneca is lagging rivals such as Bristol-Myers Squibb Co, Merck & Co and Roche Holding AG in this field.
"This is a company that has made significant progress in moving its pipeline forward over the last 18 months," said Alistair Campbell, an analyst at Berenberg Bank. "Is it enough on a fundamental basis to justify the current share price? Personally, I don't think so - at least not without the certainty you need in terms of knowing clinical trial outcomes."
Among individual products, AstraZeneca said heart drug Brilinta had the potential to deliver annual sales of around $3.5 billion by 2023, with diabetes and respiratory medicines both adding about $8 billion apiece.
In cancer it forecast potential peak sales of around $6.5 billion for its experimental immunotherapy drug MEDI4736 - the product that has excited most interest from investors and analysts.
AstraZeneca said last month it planned to push ahead with late-stage Phase III testing of MEDI4736, following evaluation of positive Phase I data that will be presented at an American Society of Clinical Oncology (ASCO) conference on May 30-June 3.
Detailed presentations on this and other experimental cancer medicines will be important and share price-sensitive catalysts for AstraZeneca and its rivals - but ASCO may come just too late for the Pfizer bid battle.
Pfizer has a deadline of May 26 to make a firm offer or walk away under British "put up or shut up" takeover rules.
"They've got drug candidates in what look to be really exciting areas," said Dan Mahony, a fund manager at Polar Capital, who raised his stake in AstraZeneca last year. "But it is not clear to us yet who, across the industry, has the best drug."
Pfizer's pursuit of AstraZeneca has created a political stir in Britain, with critics of the U.S. group's approach fearing that a takeover will lead to big cuts in drug research, despite assurances given by Pfizer to the government.
A spokesman for Prime Minister David Cameron reiterated on Tuesday that any deal would be a commercial decision for the two companies. (Additional reporting by Anjuli Davies; editing by David Stamp)