A preliminary study involving more than 300 patients from seven hospitals in Italy has found those given sitagliptin in addition to insulin had a mortality rate of 18%, compared with 37% in patients receiving only insulin.
Based on their findings, published in the journal Diabetes Care, the researchers are set to begin a randomised controlled trial of sitagliptin and are preparing to enrol patients in Europe.
Dr Paolo Fiorina, of Boston Children’s Hospital in the US, who led the research, said: “We think it’s reasonable to try sitagliptin if a patient is admitted to the hospital with type 2 diabetes and Covid.
“I’m excited about our findings, because we still have very few therapeutic options for the many diabetic patients affected by Covid.”
We think it's reasonable to try sitagliptin if a patient is admitted to the hospital with type 2 diabetes and Covid
Sitagliptin is used to lower blood sugar in type 2 diabetes and belongs to a class of drugs known as DPP-4 inhibitors.
Previous research has shown that DPP-4, an enzyme found in human cells, may also help the coronavirus that causes Covid-19 get into respiratory cells.
In addition to blocking DPP-4, sitagliptin can reduce production of a protein known as IL-6, which according to the researchers, is known to contribute to the “cytokine storm” that can cause organ complications in Covid-19.
Dr Fiorina, who is also affiliated with the University of Milan, said: “We decided to try sitagliptin and collect the data.
“Covid-19 mortality in diabetic patients is high, and the drug is very safe, so we felt there was no reason not to use it.”
Covid-19 mortality in diabetic patients is high, and the drug is very safe, so we felt there was no reason not to use it
The researchers looked at the data of 338 patients, with an average age of 69, with type 2 diabetes and Covid-19 pneumonia – who were admitted to hospital from March 1 through to April 30, 2020.
Half of them were given only IV insulin for their type 2 diabetes and served as controls, while the other half received sitagliptin in addition to IV insulin.
The two groups were matched for age and sex, and illness severity, other clinical characteristics, and use of other treatments for Covid-19 were similar in both, the researchers said.
In addition to reduced risk of mortality, the researchers found those on sitagliptin were less likely to need mechanical ventilation and need intensive care.
Dr Fiorina and colleagues believe the drug could also work in non-diabetic patients with Covid-19 and are seeking approval to test sitagliptin in Covid-19 patients without diabetes.
He said: “We must now confirm our findings in a placebo-controlled, prospective study.”