(Corrects spelling of Regeneron drug Dupixent in 14th paragraph)
ZURICH, June 20 (Reuters) - A drug developed by Novartis to treat vision loss in people over 65 does not need to be injected as frequently as a rival medicine from Regeneron to be effective, clinical trials showed on Tuesday.
Novartis said the trials showed its RTH258 drug would reduce the injection burden for patients with neovascular age-related macular degeneration (nAMD), the leading cause of vision loss for over 65s in North America, Europe, Australia and Asia.
Novartis shares climbed 1.4 percent by 1041 GMT, outperforming the Stoxx European health care sector index , with analysts saying the trial results gave RTH258 a competitive advantage over rival treatments.
Head-to-head late-stage trials showed RTH258, whose generic name is brolucizumab, worked as well as Regeneron's Eylea, with just over half the patients needing doses every 12 weeks, rather than every eight weeks for Eylea.
Cutting the frequency of injections could also give RTH258 an edge over Lucentis, another best-selling eye drug which Roche sells in the United States and Novartis sells elsewhere. Lucentis patients generally receive doses every four weeks.
"It's a positive study, we're very excited about it - it exceeds our expectations - and we're looking forward to filing in 2018" for regulatory approval, said Vas Narasimhan, Novartis's drug development chief, in an interview.
"We had hoped to see 40 percent or greater" of patients responding positively to injections every 12 weeks, he said. "Now that we see it well into the 52 to 57 percent range, we feel very good about the result."
Novartis expects RTH258 sales to eventually top $1 billion a year.
Analysts at Jefferies called the trial result "a significant differentiator and competitive advantage for RTH258".
They cited previous estimates that success in the trials could boost Novartis's earnings per share and valuation by about 2 percent in the medium term.
Zuercher Kantonalbank analyst Michael Nawrath said the data should help Novartis win back share in a highly lucrative market of 20 million to 25 million patients.
Eylea, which was developed with Bayer, has powered much of Regeneron's growth since late 2011. However, the drug's sales growth has slowed in recent quarters, mainly due to competition from Lucentis.
Lucentis topped $3.2 billion in sales in 2016 for Roche and Novartis.
Regeneron is betting on two key treatments, sarilumab for rheumatoid arthritis and Dupixent, to reduce its reliance on Eylea, which accounts for nearly 70 percent of its revenue.
Competition for nAMD patients is likely to grow even more intense, with data from trials on Abicipar, an investigational medicine being developed by Allergan and Switzerland's Molecular Partners <MOL N.S>, set for release in 2018.
Allergan is also banking on reduced injection frequency compared to Lucentis and Eylea to win over eye doctors and patients, should its drug win approval. (Reporting by Michael Shields and John Miller; editing by David Clarke)