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* 80 pct of new drugs have potential to be first-in-class
* Nucala, Shingrix, anaemia pill, antivirals highlighted
* Still sees mid-to-high single digit EPS growth 2016-2020
* Shares fall 1.5 pct (Adds further comment from CEO and analysts, closing shares)
By Ben Hirschler
LONDON, Nov 3 (Reuters) - GlaxoSmithKline could fileup to 20 new drugs for regulatory approval before 2020 as itseeks to revitalise a portfolio hit by falling sales ofbest-selling inhaled lung treatment Advair, the company said onTuesday.
Seven of them may reach the market before the end of decade,it added.
Britain's biggest drugmaker is trying to boost low investorexpectations for its pipeline by hosting its first research anddevelopment (R&D) day in more than a decade.
Investors, however, saw little to spark immediate earningsupgrades and the shares ended 1.5 percent lower.
The company highlighted projects in six core areas: HIV andother infections, respiratory medicine, oncology,immuno-inflammation, vaccines and rare diseases.
Chief Executive Andrew Witty said around 80 percent of themedicines and vaccines presented had novel mechanisms of actionthat could make them first-in-class.
"I am very confident of our ability to deliver verysubstantial new product sales growth momentum over the nextfive, 10 and 15 years," Witty said, adding GSK could file 20more products between 2020 and 2025.
Bernstein analyst Tim Anderson said the heavy focus onearlier-stage assets meant there was a high chance many productswould fail.
Investor confidence in GSK's R&D has been shaken by somehigh-profile drug failures at a time when many rivals have beenthriving, adding to pressure on Witty to revive GSK's fortunes.
He declined to comment on a report that Pfizer hadapproached GSK before entering merger talks with Allergan.
SEVERE ASTHMA
Near-term hopes hinge on new injection Nucala for severeasthma, for which a U.S. approval decision is due by Nov. 4, aswell as experimental shingles vaccine Shingrix, sirukumab forrheumatoid arthritis, a long-acting HIV medicine calledcabotegravir and daprodustat for anaemia.
Only Nucala and Shingrix were included in a GSK forecast inMay that new drugs would generate sales of at least 6 billionpounds ($9 billion) by 2020 and Witty said this figure nowlooked conservative.
Still, the company kept unchanged its forecast that coreearnings per share would grow at a mid-to-high single-digit rateat constant currencies over 2016-2020.
Despite having sold its marketed cancer drugs to Novartis, GSK is still investing in oncology and it announced adeal with Merck to test its experimental OX40 cancerdrug alongside the U.S. company's Keytruda in solid tumours.
Witty said GSK would continue to pursue new cancer avenuessuch as next-generation immunotherapies and epigenetic drugs,which can turn off cancer-related genes.
HIV drug cabotegravir will enter final Phase III testing in2016, along with daprodustat, which boosts red blood cells bymimicking the body's response to high altitude.
Fibrogen, which has deals with AstraZeneca and Astellas, already has a similar anaemia product inPhase III.
GSK also announced a collaboration with Regulus Therapeutics in hepatitis C, as well as plans for a pivotal study ofnovel antibiotic gepotidacin. JP Morgan analysts said thesePhase III decisions were largely expected.
GSK's R&D event in New York is one of three high-profileinvestor days being held by major European pharmaceuticalcompanies this week. Roche will hold a pharma day inLondon on Nov. 5, while Sanofi is hosting a strategyseminar in Paris on Nov. 6. ($1 = 0.6506 pounds) (Editing by Jason Neely and Daid Holmes)
