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Large trial rules out use of tranexamic acid for gastrointestinal bleeding


A drug licensed to treat stomach bleeding, that some doctors felt was too effective to withhold, does not improve outcome but increases side effects according to the HALT-IT clinical trial results which published in The Lancet.

Led by the London School of Hygiene & Tropical Medicine with funding and support from the NIHR, the global clinical trial of 12,000 patients with severe gastrointestinal bleeding showed that tranexamic acid, a drug that stops blood clots from breaking down failed to cut bleeding deaths but caused unwanted clots in the legs and lungs.
Gastrointestinal (GI) bleeding, from peptic ulcers, dilated gullet veins and cancer, is a common medical emergency that causes hundreds of thousands of deaths worldwide. Patients can either vomit blood or pass blood in the stools and up to 10 per cent of affected patients die. Some patients stop bleeding only to start bleeding again a short while later and these patients have particularly high death rates. Treatment includes blood transfusion and emergency surgery to tie off the bleeding vessels.

Tranexamic acid reduces bleeding in surgery and reduces deaths from bleeding after serious injury and childbirth – in both cases without increasing side effects. Only a few small trials had looked at the effect of tranexamic acid in stomach bleeding.

The HALT-IT (Haemorrhage alleviation with tranexamic acid-Intestinal system) trial is the largest ever clinical trial in gastrointestinal bleeding. Patients were recruited from 164 hospitals across 15 countries. The UK contributed the largest proportion of participants to the trial with 4,751 patients recruited from 86 hospital sites delivering the trial.

Professor Matthew Costa, National Specialty Lead for Trauma and Emergency Care, the specialty leading the study for the NIHR Clinical Research Network said:
“Previous trials have shown that tranexamic acid is effective in reducing bleeding for patients with serious injuries and after surgery, but no one knew whether or not it was effective in reducing bleeding from the stomach. The Network helped to recruit a large number of patients into the trial through collaboration between researchers in the Emergency Departments and Gastroenterology teams. We are delighted to have reached this in the agreed time and target – a key marker for the efficient delivery of research trials and studies and important for ensuring effective results.”

The results showed that tranexamic acid does not reduce deaths from stomach bleeding but increases the risk of thromboembolic events (clots in the veins of the legs that can move to the lungs). There were also more seizures with tranexamic acid. Re-bleeding was similar in both groups.

Professor Mark Hull, National Specialty Lead for the Gastroenterology specialty said of the results:
“This trial is hugely important to patient care as it shows that tranexamic acid is not effective for gastrointestinal bleeding, which is still a big cause of hospital admission and death in the UK. HALT-IT is an excellent example of the need for clinical research and how a clinical trial studying a specific cause of bleeding can uncover that one treatment doesn’t necessarily work the same for all causes of bleeding.”