Efficacy of influenza vaccine (FluVax) in patients on chemotherapy (POCT): final data analysis from South Australia

Background

Influenza (flu) virus infection has a significant morbidity and mortality in excess of 5-10% especially in patients with medical co-morbidities who are also immune-suppressed. Influenza vaccination decreases all-cause mortality by about 30-50%. Patients undergoing chemotherapy along with the general public are vaccinated annually; there has been no study to assess the efficacy of influenza vaccination in these groups (patients on chemotherapy- POCT).

Methods

This is a prospective single arm, phase II open label study. 53 POCT with non-haematological cancers were recruited between 2011 and 2012 influenza seasons. POCT vaccinated in the current influenza season were excluded. Participants had one dose of 2011/2012 trivalent FluVax containing strains A/California/7/2009(H1N1); A/Perth/16/2009 (H3N2); B/Brisbane/60/2008 at least 3 days before chemotherapy. Primary endpoint was early seroconversion (SC) rate at 3weeks; other end-points were late SC rate at 6weeks; sustained SC and sero-protection (SP) at 24 weeks. Haem-agglutination inhibition (HAI) titres in serum were measured at baseline, 3, 6 and 24 weeks. Endpoint defined as SP (HAI ≥ 40); SC (≥4-fold increase titre).

Results

53 patients; mean (sd) age 58.3(10.5) years; n(%) of Females 31(58.5). The results are displayed in the table below.

Conclusions

POCT might have sub-optimal response to the FluVax. Our findings should be confirmed in a larger patient population and warrants further research into a more effective strategy in this patient group.

Clinical trial identification

ACTRN:12611000306910

Legal entity responsible for the study

Southern Adelaide Health Network Inc

Funding

N/A

Disclosure

All authors have declared no conflicts of interest.