SINGAPORE: The Ministry of Health (MOH) has helped more than half the patients affected by the recall of three brands of high blood pressure drugs switch to alternative medicines, said Senior Minister of State for Health Lam Pin Min in Parliament on Wednesday (May 8).
The affected products, which are the 50mg and 100mg tablets from the brands Losartas, Losagen and Hyperten, were recalled on Mar 28 because they contained higher than acceptable levels of a potentially harmful impurity.
About 137,000 patients in Singapore were using the three recalled brands of losartan medicine, the Ministry of Health (MOH) had said.
Speaking in Parliament, Dr Lam said MOH is on schedule to complete the recall exercise by end June.
"As of Apr 28, we have helped more than half of the affected patients switch to alternative medicines," he said.
"For all patients whose appointments are on or after Jul 1, public healthcare institutions have already reached out to all of them to offer earlier appointments."
HSA had said that several losartan medicines have been recalled overseas since end-February due to the presence of a nitrosamine impurity, N-nitro-N-methyl-4-aminobutyric acid (NMBA).
It tested all locally marketed losartan products for the presence of the NMBA impurity and in March found the three brands contained trace amounts of NMBA above acceptable levels.
The other seven brands of losartan medicines marketed in Singapore are not affected by this impurity.
"As the short term risk of taking the medicine was low, the advisory to affected patients was to continue taking their medicines until they are provided with suitable alternatives,” said Dr Lam.
"Sudden stopping of their medication could pose greater and more immediate risk to patients’ health."
Dr Lam added: “Public healthcare institutions then scheduled appointments for affected patients to switch to alternative medicines.
"The institutions also deployed additional staff to operate the hotlines for patient queries and set up service touchpoints to help patients switch their medicines. These actions went beyond what most other countries had done.”
Testing for nitrosamines like NMBA was not previously part of the testing parameters of such angiotensin receptor blocker medicines because NMBA was not expected to be generated in the manufacturing process, said Dr Lam.
“Since the recall, HSA has also been working with suppliers and international regulatory agencies to determine the cause of contamination, and to formulate measures to eliminate the nitrosamines in the medium to longer term,” he said.
“HSA will continue to monitor the quality and safety of these medicines to safeguard public health."