* Swiss drugmaker talks up heart, cancer benefits
* Experts worry about 'modest' benefit, high price
* Novartis plans Q4 filing with regulators
By John Miller
ZURICH, Aug 27 (Reuters) - Novartis will seek regulatory approval this year for a new kind of anti-inflammatory heart drug, though some experts fear fatal infection risks and a high price may overshadow the medicine's limited benefits.
Keenly awaited clinical trial results released on Sunday showed heart-attack survivors on one of three doses of canakinumab were 15 percent less likely to suffer another major cardiac event than those on a placebo.
Novartis had said in June that the drug met its goal in the study but details were only unveiled at European Society of Cardiology meeting in Barcelona. One leading expert described the benefit as "modest".
Patients getting canakinumab also suffered significantly more deaths from infections than those on placebo - but, on the positive side, they appeared to be at lower risk of cancer.
There was no significant difference in the rate of deaths from all causes between the placebo group and those on canakinumab.
"The modest absolute clinical benefit of canakinumab cannot justify its routine use in patients with previous myocardial infarction until we understand more about the efficacy and safety trade-offs and unless a price restructuring and formal cost-effectiveness evaluation supports it," wrote Dr. Robert Harrington, chair of the Stanford University School of Medicine, in an editorial in the New England Journal of Medicine.
Canakinumab had stirred considerable scientific interest because it appears to finally deliver proof that fighting inflammation offers a promising new way to counter heart disease in patients who already get cholesterol-lowering treatment.
Subsequently, some analysts boosted their revenue estimates for the Novartis medicine into the billions of dollars, while awaiting the data announced on Sunday.
Canakinumab is already approved as Ilaris for rare autoimmune conditions.
Vas Narasimhan, Novartis's head of global drug development, said the drugmaker plans to go to regulators in the fourth quarter to seek approval for canakinumab to treat heart-attack victims with high levels of inflammation.
He downplayed critics who said the benefit was small, saying that one large subgroup in the so-called Cantos trial had shown a 27 percent reduction in cardiovascular risk.
Novartis also plans to underscore canakinumab's potential cancer fighting properties with the European Medicines Agency and the U.S. Food and Drug Administration.
That's after an analysis of Cantos data found total cancer mortality among patients getting canakinumab was significantly lower than in those receiving the placebo.
Narasimhan, who said the company now plans to start separate cancer trials for canakinumab, said the drug could be particularly suitable for smokers with risks of both lung cancer and heart problems.
Ilaris currently costs about $200,000 annually for treating rare immune conditions, though that's likely to be reduced in the heart setting, should it win approval.
Novartis initially struggled with the sluggish launch of its last heart drug, the $4,500-per-year Entresto, so it is understandably concerned about the reception for canakinumab.
While Narasimhan said it was too early to discuss pricing, he argued so-called PCSK9 cholesterol drugs that cost about $14,000 annually should not be relied on as a yardstick.
"In view of the additional oncology findings, we don't think you should just think about this as a cardiovascular drug," Narasimhan said. "I don't think you can necessarily just make comparisons to existing benchmarks, such as the PCSK9s." (Reporting by John Miller; Editing by Ben Hirschler and Ralph Boulton)