LISBON—Results of a large study revealed a higher incidence of adenovirus (AdV) infection after allogeneic hematopoietic stem cell transplant (allo-HSCT) in children than adults.

The rate of AdV infection in the 6 months after allo-HSCT was 32% in children and 6% in adults.

However, researchers believe this data may be influenced by a lack of routine AdV screening in adults.

These findings—from the AdVance study—were reported at the 44th Annual Meeting of the EBMT as abstracts OS9-7 and B043.*

Other results from AdVance were also presented at the meeting, with mortality data reported as abstract OS9-8 and hospitalization data reported as abstract B073. The AdVance study was sponsored by Chimerix, Inc.

“The robust findings of the AdVance study are extremely important for transplant clinicians, as we seek to better understand the rates and clinical outcomes of adenovirus infection and assess ways to evaluate antiviral therapies,” said study investigator Marco Zecca, MD, of Fondazione IRCCS Policlinico San Matteo in Pavia, Italy.

AdVance is a multi-center, retrospective study of 4276 allo-HSCT recipients—1738 pediatric patients and 2538 adults. The patients underwent transplants at 50 centers in Europe from January 2013 to September 2015.

Abstract OS9-7: Incidence

Thirty-two percent (n=558) of pediatric patients developed an AdV infection in the first 6 months after allo-HSCT, and 23% (n=395) developed detectable AdV viremia. Fourteen percent (n=241) had AdV viremia ≥ 1000 copies/mL, a level previously associated with negative clinical outcomes.

Meanwhile, 6% (n=141) of adults had an AdV infection in the 6 months after transplant, 3% (n=77) developed AdV viremia, and 2% (n=39) had ≥ 1000 copies /mL.

Further analysis revealed that age, donor type, and use of T-cell depletion were independent predictors of AdV viremia ≥ 1000 copies/mL.

Older age was associated with a lower risk of AdV viremia ≥ 1000 copies/mL. There was a stepwise reduction in risk with increasing age (compared to ages 0-2, P=0.104 for ages 2-12, P=0.001 for ages 13-17, and P<0.0001 for ages 18-65+).

T-cell depletion was associated with an increased risk of AdV viremia ≥ 1000 copies/mL. Compared to no T-cell depletion, there was an increased risk for depletion with antithymocyte globulin (P=0.036) or alemtuzumab (P<0.0001) and for ex vivo depletion (P=0.002).

Compared to patients who received a matched related transplant, recipients of other transplants had an increased risk of AdV viremia ≥ 1000 copies/mL. This includes matched unrelated (P=0.016), cord blood (P=0.011), haploidentical (P=0.007), and mismatched (P<0.001) transplants.

Abstract B043: Screening

Dr Zecca and his colleagues believe the difference in AdV incidence between children and adults may have been affected by a lack of routine screening in adults.

To assess the use of screening, the investigators analyzed practice surveys from physicians at centers included in the AdVance study. There were 28 survey respondents who treat pediatric patients and 14 who treat adults.

All 28 physicians treating pediatric patients said there is routine AdV screening at their center. Ninety-three percent of these doctors said they routinely screen all pediatric allo-HSCT recipients for AdV infection. The remaining 7% said they screen patients considered to be at high-risk of AdV infection.

Thirty-six percent of the physicians treating adults (5/14) said they routinely screen for AdV, and 21% (3/14) said they routinely screen all of their adult allo-HSCT recipients for AdV infection.

Of the 11 doctors who said they did not routinely screen adult allo-HSCT recipients, some said they would screen recipients with a high-risk of AdV infection, such as those with graft-versus-host disease (4/11) or those who received haploidentical, mismatched, or cord blood transplants (3/11).

*Data in the abstracts differ from the presentations.

Kids may have higher rate of AdV infection after HSCT