Skip to main content

Advertisement

SpringerLink
Log in

Demand Forecasting for Preventive AIDS Vaccines

Economic and Policy Dimensions

  • Original Research Article
  • Published:
PharmacoEconomics Aims and scope Submit manuscript

Abstract

Background

An AIDS vaccine could play a very significant role in reversing the HIV pandemic, saving millions of lives. For a vaccine to have such an impact, it must be widely available and adopted and taken up rapidly in the countries most affected. A demand-forecasting model provides a valuable tool that can guide R&D spending decisions and identify policy actions to help achieve these goals.

Objective

To identify the key determinants of vaccine demand, model global adoption and uptake dynamics, estimate potential demand and revenues associated with future preventive AIDS vaccines, and to conduct sensitivity analyses to assess the impact of each parameter on demand.

Methods

A discrete, deterministic, linear, predictive mathematical model based on stratified population averages with a 30-year time horizon was developed to assess scenarios of future demand. This forecasting model was used to explore the effects of vaccine characteristics and a variety of regulatory, political, financial and health service factors on future demand and revenues.

The intervention modelled was a preventive AIDS vaccine (efficacy: 30–90%; duration of protection: 3–5 years; in a two-dose prime-boost combination). The main outcome measure was the number of complete courses of vaccine administered.

Results

The model suggests that demand for a preventive AIDS vaccine with a medium efficacy (50%) and duration of protection (3 years) would average 68 million courses annually over a 30-year period. Under different scenarios, demand would peak at 38–152 million courses annually. On the basis of tiered pricing across public and private markets ($US2–100 per dose), these levels of peak demand would translate into $US2.5–5.5 billion in peak annual sales revenues.

Private markets and high-income countries account for small volumes but large shares of projected revenues, while low-income countries account for large volumes and more modest, but still significant, sales revenues. Vaccinations to ‘catch-up’ those who are missed or not eligible for routine annual programmes (whether adolescent or high-risk populations) would account for 20–35% of cumulative vaccination courses across all scenarios.

Demand was found to be sensitive to vaccine efficacy, duration of protection and price. Efforts to expedite regulatory review processes, improve immunization infrastructure and reduce political constraints could increase demand for an AIDS vaccine by 40 million additional courses a year compared with the medium efficacy (baseline) vaccine forecast.

Conclusions

Our model can provide vaccine developers with credible estimates of market potential for an AIDS vaccine, and with a tool that can be used to improve forecasts over time as AIDS vaccine science progresses. It can also help governments to identify and pursue those policies that could best strengthen demand and uptake of a safe and effective preventive AIDS vaccine.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Fig. 1
Table I
Table II
Table III
Table IV
Table V
Table VI
Table VII
Fig. 2
Fig. 3
Table VIII
Fig. 4
Table IX
Fig. 5
Table X
Fig. 6
Table XI

Similar content being viewed by others

Notes

  1. Eighty stakeholder interviews were conducted across the world, surveying policy makers and influencers of policy; namely, government advisers and civil servants, academics, non-government organization personnel, pharmaceutical executives and vaccine researchers. The perceptions/preferences of each stakeholder group were sought with respect to the likely characteristics (including price) of a first-generation AIDS vaccine, the associated vaccination strategy that would be employed, and the likely effectiveness (reach/coverage) of such strategies. This helped define country/regional inputs with respect to particular drivers of demand. For a full list of interviewees and collaborators see the International AIDS Vaccine Initiative[2].

  2. The year of licensure is an assumption made within the model — the chosen year is hypothetical, yet it is necessary to specify it because the year is a crucial determinant of the size of populations around the world who might be targeted for vaccination.

  3. We defined an efficacy of 50% as implying that for every ten people vaccinated, five would be fully protected against HIV no matter how risky their behaviour. This is known as ‘take-type’ efficacy in that the vaccine ‘takes’ or has an effect in a proportion of those vaccinated. Researchers have considered other definitions of efficacy for HIV vaccines (e.g. ‘degree-type’ efficacy);[4,26,27] however, for the purposes of our stakeholder interviews, we chose the simpler and cognitively intuitive definition.

References

  1. Sekhri N. Forecasting for global health: new money, new products and new markets [background paper]. Washington, DC: Center for Global Development, 2006

    Google Scholar 

  2. International AIDS Vaccine Initiative. Forecasting the global demand for preventive HIV vaccines [policy research working paper no. 15]. New York: IAVI, 2007

    Google Scholar 

  3. International AIDS Vaccine Initiative. Estimating the global impact of an AIDS vaccine [policy research working paper no. 4]. New York: IAVI, 2005

    Google Scholar 

  4. International AIDS Vaccine Initiative. The impact of an AIDS vaccine in developing countries: a new model and preliminary results [policy research working paper no. 8]. New York: IAVI, 2006

    Google Scholar 

  5. The United Nations Joint Programme on HTV/AIDS. 2007 AIDS epidemic update. Geneva: UN AIDS, 2007

    Google Scholar 

  6. International AIDS Vaccine Initiative. Demand for a preventive HIV vaccine: a review of the literature [policy research working paper no. 3]. New York: IAVI, 2005

    Google Scholar 

  7. Esparza J. Potential vaccination strategies using HIV vaccines in developing countries [background paper; GPA/IFP.4/93.8]. Fourth meeting of the WHO-IFPMA Working Group on the development, testing, utilization and supply of drugs and vaccines for HIV infection and HIV-related disease; 1993 Feb 1–2; Geneva

    Google Scholar 

  8. Bishai D, Lin MK, Kiyonga CWB. Algorithms for purchasing AIDS vaccines [World Bank policy research working paper no. 2321]. Washington, DC: World Bank 2000

    Google Scholar 

  9. Esparza J, Chang ML, Widdus R, et al. Estimation of ‘needs’ and ‘probable uptake’ for HIV/AIDS preventive vaccines based on possible policies and likely acceptance (a WHO/ UNAIDS/IAVI study). Vaccine 2003; 21: 2032–2041

    Article  PubMed  Google Scholar 

  10. International AIDS Vaccine Initiative. An advance market commitment for AIDS vaccines: accelerating the response from industry [policy research working paper no. 7]. New York: IAVI, 2005

    Google Scholar 

  11. Shaffer C, Brandewinder M, Wroebel S, et al. Applied strategies: analysis using the AMC-FIRM model. San Mateo (CA): Applied Strategies, 2007. Data on file

    Google Scholar 

  12. Medicines for Malaria Venture. Planning for success: analysis conducted by the Bill and Melinda Gates Foundation and the Boston Consulting Group. Boston (MA): Medicines for Malaria, 2005 (data on file)

    Google Scholar 

  13. Longhi A, Chisholm R, Rilling M, et al. Principles for forecasting demand for global health products. Washington, DC: Center for Global Development Forecasting Principles Mini-Group, 2006

    Google Scholar 

  14. McCluskey MM, Alexander SB, Larkin BD, et al. An HTV vaccine: as we build it, will they come? Health Aff (Millwood) 2005; 24 (3): 643–651

    Article  Google Scholar 

  15. World Health Organization. Selected vaccine introduction status into routine immunization worldwide, 2003. Geneva: WHO, 2003 [online]. Available from URL: http://www.who.int/immunization_monitoring/routine/schedule_analysis_2003.pdf [Accessed 2008 Jan 15]

    Google Scholar 

  16. International AIDS Vaccine Initiative. Forecasting the global demand for preventive HIV vaccines [policy research working paper no. 15, appendices III-IV]. New York: IAVI, 2007

    Google Scholar 

  17. Central Intelligence Agency. Age structure/distribution by country [online]. Available from URL: https://www.cia.gov/library/publications/the-world-factbook/index.html [Accessed 2008 Jun 23]

  18. United Nations Secretariat. Department of Economic and Social Affairs. Population Division. World population prospects: the 2004 revision [online]. Available from URL: http://www.un.org/esa/population/publications/WPP2004/2004Highlights_finalrevised.pdf [Accessed 2008 Jun 23]

  19. Vandepitte J, Lyerla R, Dallabetta G, et al. Estimates of the number of female sex workers in different regions of the world. Sex Transm Infect 2006; 82 Suppl. 3: iii18–iii25

    Article  PubMed  Google Scholar 

  20. Aceijas C, Stimson GV, Hickman M, et al. Global overview of injecting drug use and HIV infection among injecting drug users. AIDS 2004; 18 (17): 2295–2303

    Article  PubMed  Google Scholar 

  21. Cáceres C, Konda K, Pecheny M, et al. Estimating the number of men who have sex with men in low and middle income countries. Sex Transm Infect 2006; 82 Suppl. 3: iii3–iii9

    Article  PubMed  Google Scholar 

  22. The United Nations Joint Programme on HIV/AIDS. Report on the global AIDS epidemic: annex 1. Country profiles. Geneva: UNAIDS, 2006: 374

    Google Scholar 

  23. USAID, UNAIDS, WHO, and the POLICY Project. The level of effort in the national response to HIV/AIDS: the AIDS program effort index (API) 2003 round. Washington, DC: USAID, 2003 [online]. Available from URL: http://www.policyproject.com/pubs/monographs/API2003.pdf. [Accessed 2006 Jun 10]

    Google Scholar 

  24. World Bank. GNI per capita 2005: Atlas method and purchasing power parity [online]. Available from URL: http://siteres ources.worldbank.org/ICPINT/Resources/Atlas_2005.pdf [Accessed 2008 Jun 23]

  25. The Global Fund to fight AIDS, Tuberculosis and Malaria (GFATM). Resource needs: funding the global fight against HIV/AIDS, tuberculosis and malaria. Resource needs for the global fund 2008–2010. GFATM 2007 [online]. Available from URL: http://www.theglobalfund.org/en/files/about/replenishment/oslo/Resource%20Needs.pdf [Accessed 2006 Aug 22]

  26. Blower SM, McLean AR. Prophylactic vaccines, risk behavior change, and the probability of eradicating HTV in San Francisco. Science 1994; 265 (5177): 1451–1454

    Article  PubMed  CAS  Google Scholar 

  27. McLean AR, Blower SM. Modelling HIV vaccination. Trends Microbiol 1995; 3 (12): 458–462

    Article  PubMed  CAS  Google Scholar 

  28. Rogers EM. Diffusion of innovations. 4th ed. New York: The Free Press, 1995: 22–23

    Google Scholar 

  29. Andre F. How the research-based industry approaches vaccine development and establishes priorities. Developmental biology 2002; 110: 25–29

    CAS  Google Scholar 

  30. International AIDS Vaccine Initiative. Speeding the manufacture of an HIV vaccine: policy issues and options [policy discussion paper]. New York: IAVI, 2005

    Google Scholar 

  31. Van Exan R. BIOTECanada Vaccine Industry Committee. Current challenges in immunization: the delicate balance of vaccine supply and demand [presentation]. Ottawa (ON): BIOTECanada, 2004 [online]. Available from URL: http://www.phac-aspc.gc.ca/cnic-ccni/2004/pres/_pdf-wed-mec/2_VAN_EXAN_ROB_Wednesday_210ae.pdf [Accessed 2006 Oct 6]

    Google Scholar 

  32. Cohen J. Shots in the dark: the wayward search for an AIDS vaccine. New York: Norton, 2001

    Google Scholar 

  33. Kalorama information. Vaccines: the world market. Rockville (MD): Kalorama information, 2007 [online]. Available from URL: http://www.kaloramainformation.com/Vaccines-1351010/ [Accessed 2007 May 5]

    Google Scholar 

  34. IMS Health. Vaccines: an antidote to sluggish pharma sales? [online]. Available from URL: http://www.imshealth.com/web/end/0,3150,64576068_63872702_82367711,00.html [Accessed 2008 Jun 17]

  35. Barth-Jones DC, Cheng H, Kang LY, et al. Cost effectiveness and delivery study for future HIV vaccines. AIDS 2005; 19 (13): wl–w6

    Google Scholar 

  36. Barth-Jones DC, Longini Jr IM. Determining optimal vaccination policy for HIV vaccines: a dynamic simulation model for the evaluation of vaccination policy. In: Anderson JG, Katzper M, editors. Proceedings of the International Conference on Health Sciences Simulation 2002 Western Multiconference; 2002 Jan 27–31; San Antonio (TX): 6–79

Download references

Acknowledgements

The authors wish to thank Christoph Kaufmann, Dave Matheson, Wendy Woods and Michael Yeh of the Boston Consulting Group for their contributions to this research project, particularly the primary data collection and modelling work. Thanks also to Paul Wilson, Shilpa Vuthoori and Holly Wong at the International AIDS Vaccine Initiative (IAVI), Eva Roca at the Population Council (formerly of IAVI) and the members of the external advisory group who steered the project.

This work was funded by the US Agency for International Development (USAID). This organization played no role in the design and conduct of the study; collection, management, analysis and interpretation of data; or preparation, review or approval of the article.

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or a financial conflict with the subject matter or materials discussed in the article. This includes employment, consultancies, honoraria, stock ownership or options, grants or patents received or pending, or royalties.

This article is an edited and shortened version of an IAVI policy research working paper.[2]

Author information

Authors and Affiliations

  1. International AIDS Vaccine Initiative (IAVI), 110 William Street, 28th Floor, New York, New York, 10038, USA

    Robert Hecht &  Gian Gandhi

Authors
  1. Robert Hecht
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Gian Gandhi
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Gian Gandhi.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Hecht, R., Gandhi, G. Demand Forecasting for Preventive AIDS Vaccines. Pharmacoeconomics 26, 679–697 (2008). https://doi.org/10.2165/00019053-200826080-00005

Download citation

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.2165/00019053-200826080-00005

Keywords

Search

Navigation