AstraZeneca potassium drug delayed by manufacturing snag

LONDON (Reuters) - AstraZeneca said on Friday U.S. regulators would not approve its new drug for high potassium levels at present due to a manufacturing issue, dealing a blow to a product acquired when it bought ZS Pharma for $2.7 billion (1.8 billion pounds) last year. Analysts said the drug's launch would now likely be delayed until 2017 after the British drugmaker said the Food and Drug Administration (FDA) had issued a so-called complete response letter (CRL) for ZS-9, or sodium zirconium cyclosilicate. Such letters typically outline concerns and conditions that must be addressed to gain U.S. approval. "The CRL refers to observations arising from a pre-approval manufacturing inspection," AstraZeneca said. "The FDA also acknowledged receipt of recently submitted data which it has yet to review. The CRL does not require the generation of new clinical data." A spokesman said the company hoped to resolve the matter in a "timely" manner. Berenberg analysts said AstraZeneca would probably face a six-month review once it refiled with the FDA. "Assuming the company can refile in a matter of months, an approval in Q1 2017 could be possible," they wrote in a note. The setback offset positive news from a clinical trial testing Faslodex in breast cancer, which may boost sales of that medicine. Buying ZS Pharma was one of several bolt-on acquisitions by AstraZeneca designed to help build up its pipeline of new drugs. ZS-9 treats hyperkalaemia, or high potassium levels, which is typically associated with chronic kidney disease and chronic heart failure. AstraZeneca said when the acquisition was announced in November that its peak sales were forecast to exceed $1 billion. (Reporting by Ben Hirschler; Editing by Alexander Smith)