Surveillance of adverse events after the first trivalent inactivated influenza vaccine produced in mammalian cell culture (Flucelvax(®)) reported to the Vaccine Adverse Event Reporting System (VAERS), United States, 2013-2015.

BACKGROUND

In November 2012, the first cell cultured influenza vaccine, a trivalent subunit inactivated influenza vaccine (Flucelvax(®), ccIIV3), was approved in the US for adults aged ≥ 18 years.

OBJECTIVE

To assess adverse events (AEs) after ccIIV3 reported to the US Vaccine Adverse Event Reporting System (VAERS), a spontaneous reporting surveillance system.

METHODS

We searched VAERS for US reports after ccIIV3 among persons vaccinated from July 1, 2013-March 31, 2015. Medical records were requested for reports classified as serious (death, hospitalization, prolonged hospitalization, disability, life-threatening-illness), and those suggesting anaphylaxis and Guillain-Barré syndrome (GBS). Physicians reviewed available information and assigned a primary clinical category using MedDRA system organ classes (SOC) to each report. Empirical Bayesian data mining was used to identify disproportional AE reporting following ccIIV3.

RESULTS

VAERS received 629 reports following ccIIV3 of which 313 were for administration of vaccine to persons <18 years. Among 309 reports with an AE documented, 19 (6.1%) were serious and the most common categories were 152 (49.2%) general disorders and administration site conditions (mostly injection site and systemic reactions) and 73 (23.6%) immune system disorders with two reports of anaphylaxis. Four reports of GBS were submitted. Disproportional reporting was identified for 'drug administered to patient of inappropriate age.'

CONCLUSIONS

Review of VAERS reports did not identify any concerning pattern of AEs after ccIIV3. Injection site and systemic reactions were the most commonly reported AEs, similar to the pre-licensure clinical trials. Reports following ccIIV3 in persons <18 years highlight the need for education of healthcare providers regarding approved ccIIV3 use.