Novartis drug cuts recurrence risk by 25% in early-stage breast cancer

FRANKFURT, June 2 (Reuters) - Novartis breast cancer drug Kisqali cut the risk of recurrence by more than 25% in a pivotal trial on women diagnosed at an early stage, positioning the Swiss drugmaker to win new patients and but facing strong competition from Eli Lilly.

The company on Friday said the relative risk reduction of cancer recurrence was 25.2% and that the results were broadly consistent regardless of patients' menopausal status or cancer progression status. The results were presented at the annual meeting of the American Society of Clinical Oncology in Chicago.

The Swiss drugmaker's shares rose, even as the efficacy read-out fell short of that of a drug by Lilly, but a more favourable side effect profile might swing the balance in favour of Kisqali.

The drug was used in the trial together with standard endocrine therapy to treat a type of cancer that grows in response to hormones and it was compared to endocrine therapy alone.

The Novartis treatment has been approved to treat hormone-driven breast cancer that has spread to other parts of the body, where Novartis has taken market share from Pfizer's Ibrance.

But an earlier diagnosis, when tumours can still be surgically removed, is much more common, representing about 90% of patients.

Still, better drugs are needed after surgery because the cancer later returns in between a third and one half of cases.

Eli Lilly is ahead with the approval of rival drug Verzenio in the early setting. But that is in a subset of women who are at high risk of recurrence after surgery, typically diagnosed based on signs of cancer in the lymph nodes.

Here, Novartis will face tough competition because the U.S. drugmaker has said Verzenio reduces the risk of recurrence by 35% in that group.

But Kisqali looks set to be a pioneer in a wider market because it was tested successfully in both high-risk and medium-risk patients, a population that is twice as large.

Analysts have said investors could be disappointed if the Kisqali read-out fell well short of Verzenio's efficacy and Jefferies analysts said on Friday the efficacy read-out was "closer to our downside scenario".

But Novartis stressed very low rates of symptomatic side effects in its trial, important to patients facing years-long treatment, with severe diarrhoea affecting only 0.6% of participants on Kisqali.

That compares with 8%-20% of the women in trials with Eli Lilly's Verzenio being affected by severe diarrhoea.

"This may be very relevant commercially," said Evercore ISI analyst Umer Raffat.

Novartis shares were up 1.5% at 1430 GMT, rebounding from initial losses after the news. Lilly shares gained 0.9%.

"We know diarrhoea can be a very troublesome, burdensome adverse event for patients taking anti-cancer medicines," said Jeff Legos, Head of Oncology & Hematology Development at Novartis.

The March trial update boosted market confidence in targets issued by CEO Vas Narasimhan for annual sales growth of 4% through 2027 and a core operating income margin of 40% from 2027, analysts have said.

Novartis will request approval for wider use in the U.S. and Europe before the end of the year, it added.

Novartis gave a brief preview of the Kisqali data in March, boosting its shares and growth prospects.