* Banks on cancer, heart, respiratory treatments
* To file serelaxin for EU, US approval in early 2013 (Adds details)
ZURICH, Nov 8 (Reuters) - Novartis gave an upbeat assessment of the battle to overcome patent expiries in its top drugs, saying it could produce 14 or more blockbusters within five years as it bets on cancer, heart and respiratory treatments.
The Swiss drugmaker said it had 139 projects in clinical development including more than 73 new molecular entities spread across a wide area of diseases.
Among its most promising products are serelaxin and LCZ686 to treat patients with heart failure as well as drugs for psoriasis and multiple sclerosis.
Novartis said it plans to file serelaxin for regulatory approval in the United States and Europe in early 2013.
However, results of a late-stage study for serelaxin published on Tuesday were mixed and some analysts think Novartis may need further trials to guarantee its commercial success.
The drugmaker, in a statement published ahead of an investor event in Boston on Thursday, was also confident about its oncology pipeline, which it expects to contribute more than $1 billion in sales by 2017, pointing to the planned launched of BKM120 for various tumours and LDK378 in lung cancer.
Like its rivals, Novartis is facing the expiry of patents on its top earners, particularly Diovan for high blood pressure. It is banking on sales of its newest products, such as multiple sclerosis pill Gilenya and breast cancer drug Afinitor to pump up its sales.
Novartis said Afinitor, which got the nod from EU regulators in July, could have sales of $2 billion in advanced breast cancer by 2017.
It is also hoping to protect its cancer franchise by convincing doctors to switch patients on to Tasigna, when one of its best-selling drugs Glivec loses patent protection in 2014.
Novartis plans to initiate further trials in 2013 to prove that patients with chronic myloid leukaemia who have taken Tasigna may be able to stop treatment once their cancer is under control.
Novartis said it planned to manage more projects but keep a lid on costs by cutting recruitment time and spending on trials.
Its cross-town rival Roche has also pledged to keep R&D spending stable, as drugmakers come under pressure from patent expiries and squeezed European healthcare budgets. (Reporting by Caroline Copley; Editing by David Cowell)