(Adds details on probe)
July 25 (Reuters) - The UK Competition and Markets Authority (CMA) on Thursday said it had found provisionally that sellers of antibiotic Nitrofurantoin broke competition law by "arranging to carve up the market between them".
The watchdog said from 2014 to at least October 2017, two suppliers, Advanz Pharma Corp and Morningside, and a wholesaler, Alliance Healthcare, entered into arrangements under which Alliance would buy equal volumes of the drug from each of the suppliers so that they would not compete.
During 2015 and 2016, the two suppliers also committed to supply the drug exclusively to Alliance, the watchdog added.
Nitrofurantoin is one of the most effective options for treating urinary tract infections (UTIs) like cystitis which are among the most common infections world-wide and have become a focal point for concerns about growing bacterial resistance to antibiotics.
"We've provisionally found that suppliers of this important antibiotic entered into arrangements with the aim of keeping Nitrofurantoin capsule prices artificially high, meaning the NHS wouldn't benefit from the lower prices that come from effective competition," said Ann Pope, the CMA's Senior Director of Antitrust.
The CMA said the investigation had focussed on the capsule form of Nitrofurantoin rather than tablets or liquid versions.
AMCo, now known as Advanz and formerly Concordia International Corp, was the sole UK supplier of both products, until Morningside entered the market in mid-2014, the watchdog said. (Reporting by Justin George Varghese and Ankur Banerjee in Bengaluru; editing by Patrick Graham)