A US study has been hailed a potential breakthrough in the treatment of recurrent Clostridium difficile by paving the way for a pill to tackle the deadly superbug.
The findings – published in the journal Alimentary Pharmacology and Therapeutics – could mean thousands of patients being spared the inconvenience and discomfort of current procedures used to treat C difficile in persistent cases.
“Freeze-dried product can be put into a pill that can be given orally”
The study authors noted that most people who contract C difficile are treated with antibiotics in the first instance but it may not be enough to see off the infection with C difficile spores lurking in the gut and leading to repeat attacks.
Patients blighted by recurrent diarrhoea that lasts months or even years can be successfully treated by replenishing their gut with “good” bacteria extracted from the faeces of a healthy donor.
The procedure – known as fecal microbiota transplantation (FMT) – is usually done with live bacteria transferred to the C difficile patient via a colonoscopy, endoscopy, sigmoidoscopy or enema.
However, the study by researchers from the University of Texas and Kelsey Research Foundation is said to be the first show that frozen and freeze-dried products are almost as effective.
Senior author Dr Herbert Dupont said the findings could see an end to the “logistical nightmare” of using fresh bacteria for FMT.
“If we were going to treat you today, a donor would have to come in two hours before,” he said. “We would have already isolated the sample and would have to administer it the same day. A pill form of the product could make all of this easier.”
More than 70 patients who had suffered at least three bouts of recurrent C difficile took part in a clinical trial where they were treated with fresh, frozen or freeze-dried FMT material via a colonoscopy.
While the freeze-dried product was less effective in curing infection outright, the research team found it “resembled other products” when it came to restoring a healthy mix of bacteria in the gut after a month.
They found fresh product cured everyone who received it, while the frozen product cured 83% of those who got it and the freeze-dried material cured 69%.
The frozen and fresh product fully restored healthy bacteria in the gut within a week of treatment. Meanwhile, researchers found some improvement in patients treated with the freeze-dried product after seven days and healthy bacteria was restored within 30 days.
‘Pill’ on horizon for treating recurrent C difficile infection
The research team said these results indicated the frozen and freeze-dried product were pretty much “as good” as fresh material.
However, the freeze-dried product comes with the major advantage of being able to be turned into a simple pill.
“Freeze-dried product can be put into a pill that can be given orally, which is much more convenient for patients and physicians,” said Dr Dupont, who co-directs the FMT research programme with Dr Zhi-Dong Jiang.
The team is currently testing the safety and effectiveness of a pill version of the treatment.
The study suggests the “slightly reduced efficacy” of the freeze-dried material may be because less of the “good” bacteria survived the freezing process.
The researchers are now exploring the possibility of boosting the amount of bacteria contained in the prototype pills and looking at ways of protecting it during the freezing process.