Skip to main content

Archived Comments for: A meta-analysis of the effect of antibody therapy for the prevention of severe respiratory syncytial virus infection

Back to article

  1. Antibody therapy for for the prevention of severe respiratory syncytial virus infection

    Bosco Paes, McMaster University

    5 August 2009

    To the Editor:
    We read with interest the article by Morris SK et al addressing the effect of antibody therapy for the prevention of respiratory syncytial virus (RSV) infection.1 The primary objective was to determine the impact of RSV-IVIG and palivizumab on the risk of RSV related hospitalization and secondly to determine if antibody therapy decreases the risk of RSV infection, intensive care admission, mechanical ventilation and mortality in high risk populations. Meta-analyses are typically conducted to enhance the precision of treatment effects, provide information for the timely introduction of effective treatments and to help guide rational treatment decisions by practicing physicians.

    Unfortunately, the results derived specifically from the pooled analyses of the three RSV-IVIG trials are outdated and have limited value in current everyday practice. As the authors indicate, RSV-IVIG has not been available through the Canadian Blood Services since October 2005, was similarly discontinued in the USA in 2003 and the product was never licensed for general use in Europe. Therefore the data on the relevance of RSV-IVIG as a therapeutic intervention is entirely historical and offers little in terms of general applicability. The inclusion of the RSV-IVIG clinical trials in the meta-analysis also impacts the overall results, precision and interpretation of the statistically significant effects of both the primary and secondary outcomes displayed in majority of the figures and tables. This dilutes the contribution of palivizumab alone to the overall end points for an evidence-based consumer.

    The authors broadly discuss the cost-effectiveness (CE) of palivizumab and rightly indicate that this may differ across countries and have limited generalizability. They misquote the reference to a recent Canadian study (2) which determined that the incremental cost-effectiveness ratio (ICER) for palivizumab prophylaxis in the base-case scenario was $20,924 per quality adjusted life year (QALY) from the payer’s perspective, which is considered cost-effective in Canada. This is followed by a second misquoted reference of a comprehensive systematic review of cost-effective studies conducted across Canada, the United Kingdom and the United States (3) which concluded that the unselective use of palivizumab in any of the licensed indications did not represent good value. The review by Wang et al principally focused on the applicability of palivizumab in the UK using the specific Birmingham Economic Evaluation model (BrumEE). The single Canadian study (4) referenced in the discussion section of this paper, identified that there were no rigorously conducted CE studies available in Canada, except for the limited information available on the costs of palivizumab (5). It seems therefore that the authors contradict their original statement regarding the generalizability of CE studies and include Canada under the umbrella after previously referencing a cost-effective ICER for infants 32-35 completed weeks gestational age.
    In summary, while the meta-analysis is technically sound, it unfortunately addresses a clinically irrelevant question. Furthermore, no conclusions about cost-effectiveness can be made from these data. The selective inclusion of trials that only target the use of palivizumab for adoption into clinical practice would be much more relevant.

    Bosco Paes, MBBS
    Department of Pediatrics, McMaster Children’s Hospital
    McMaster University, Hamilton, Ontario, Canada

    Krista Lanctot, PhD
    Sunnybrook Health Sciences Centre,
    University of Toronto, Toronto, Ontario, Canada

    1)Morris SK, Dzolganovski B, Beyene J, Sung L. A meta-analysis of the effect of antibody therapy for the prevention of severe respiratory syncytial virus infection. BMC Infect Dis 2009;9:106 doi:10.1186/1471-2334-9-106
    2)Lanctot KL, Masoud ST, Paes BA, Tarride J-E et al. The cost-effectiveness of palivizumab for respiratory syncytial virus prophylaxis in premature infants with a gestational age of 32-35 weeks: a Canadian based analysis. Curr Med Res Opin 2008;24(11):3223-37
    3)Wang D, Cummins C, Bayliss S, Sandercock J, Burls A. Immunoprophylaxis against respiratory syncytial virus (RSV) with palivizumab in children: a systematic review and economic evaluation. Health Technol Assess 2008;12(36):iii, ix-x, 1-86
    4)Dunfield L, Mierzwinski-Urban M. Palivizumab prophylaxis against respiratory syncytial virus. Canad Agency Drugs Technol Health 2007;80:1-9
    5)Robinson JL, Lee BE. Prophylaxis of respiratory syncytial virus in Canada in 2003. Paediatr Child Health 2003;8(10):609-12

    Competing interests