LONDON U.S. regulator the Food and Drug Administration (FDA) intends to ban unapproved oral colchicine products to treat gout, according to a document posted online by the U.S. Office of the Federal Register.
Shares in Hikma Pharmaceutical, a company that will be impacted by the move, closed down 4.2 percent at 688.5 pence, after earlier falling as much as 7.5 percent, after analysts cited the document.
Oral colchicine has been available since the nineteenth century, but was only approved by the FDA last year when it cleared Mutual Pharmaceutical's Colcrys product, which is based on the drug.
Several companies, but not Hikma, were asked to pull unapproved colchicine products earlier in the year.
Hikma kept its medicine, made by its generics division, on the market, helping boost its first-half sales in the United States by 41 percent.
The latest statement, visible here was due to be officially published on October 1 but will not come as a surprise to Hikma, which had said it expected growth in its U.S. generics division to slow to about 20 percent or more in the second half.
Numis analyst Jonathan Kwok said in a note on September 17 that much of Hikma's first-half earnings beat was down to colchicine, and he calculated that the firm recognized about $30 million of sales in the period, generating gross profits as high as $25 million.
"If the FDA follows its official guidance of a 'one year grace period', Hikma's colchicine is due to be pulled from the market any time now," he said in the September note.
Hikma said it had not been directly contacted by the FDA.
A spokeswoman said: "Hikma would of course comply if it receives a request or notification to stop selling colchicine."
(Reporting by Paul Sandle; Editing by David Holmes)