Number Of Rotavirus Vaccine-Associated Cases Of Intussusception Escalates

September 15, 1999

BETHESDA, MD, Sept 15 (Reuters Health) - The Food and Drug Administration

(FDA) has received reports of 99 cases of intussusception that may be

related to Wyeth-Ayerst's RotaShield rotavirus vaccine, an FDA medical

officer said Tuesday.

The number of previously noted cases was 15, as of July 7.

Two of the 99 children who developed intussusception died, according to

FDA's Dr. Carbone, one of the initial reviewers of the RotaShield

data. All had been given at least one dose of RotaShield.

RotaShield was approved in August 1998. Soon after its introduction, the

FDA's Vaccine Adverse Event Reporting System (VAERS) began receiving reports

of children having intussusception shortly after being vaccinated. By July

7, the VAERS had 15 cases logged, and on July 17, the Centers for Disease

Control and Prevention (CDC) urged physicians and parents to postpone

rotavirus vaccination until investigators could determine whether RotaShield

was causing intussusception.

The number of cases reported to the VAERS spiked after the CDC report, Dr.

Carbone said. All are still under investigation, so it is not clear yet

whether the two deaths or the other cases were caused by the vaccine, she

said. " This is very preliminary information, " she told a gathering of the

FDA's Vaccines and Related Biological Products Advisory Committee.

In a post-marketing study conducted in infants at an HMO, there were nine

total cases of intussusception in 9,802 children, but only three were in

those who received RotaShield, Dr. Carbone indicated.

The CDC is continuing its own case-control study, focusing on all cases of

intussusception in states that had the highest distribution of rotavirus

vaccine. The agency is expected to report preliminary data in early

November, after enrollment ends.

Depending on what CDC finds, the FDA will decide what to do with RotaShield

and how future rotavirus vaccines should be evaluated, Dr. Carbone said.

The FDA is also investigating preliminary reports of intussusception that

may be related to the oral polio vaccine.

In the meantime, the Association of American Physicians and Surgeons urged

Congress on September 2 to start an inquiry into the FDA's vaccine approval

process, claiming that the RotaShield approval may indicate problems with

the system.

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