Legal Scholarship


Patent Information, Freedom to Operate and “Global Access”: A Case Study of Dengue Vaccines Under Development


This Global Challenges Report1 presents a “global access” freedom to operate (FTO) analysis2 of six vaccines under development against dengue hemorrhagic fever (hereinafter referred to as “dengue”), a Neglected Tropical Disease (NTD)3 endemic to tropical regions. Developing a vaccine against dengue is challenging because there are four closely related viruses that can cause the disease. Several vaccines are in various stages of development, including by developing country institutions from both the public and private sector. Clinical trials are underway on five candidate vaccines with encouraging results. After an extended executive summary (Section 1) and an introduction and description of the methodology (Section 2), the report reviews the scientific basis of the various vaccines under development (Section 3). A successful vaccine should immunize against all four types, and substantial progress towards the development of such a vaccine has been made in the last decade. The range of vaccines under development include live attenuated vaccines, live chimeric virus vaccines and live recombinant, DNA and subunit vaccines. Each type comes with its own unique challenges and benefits, though live attenuated vaccines have been the most successful to date4. Section 4 presents the patent situation relating to six of the dengue vaccines under development. Some 10,800 patents and patent applications were found to have “dengue” in the abstract, title, text or claims, corresponding to 4,500 patent families. Of these, 700 families were found to be outside the scope. Of the remaining 3,800 patent families, 55 patents or patent families were deemed pertinent to the six vaccines discussed in this report. The number of patent families related to a given vaccine ranged from five to 22. Most of these were filed in developed countries with only a small number also filed in select developing countries. Each of the patent groups occupied a well-defined space in the patent landscape, with little overlap in the specific technological field. This finding has important implications for IP management strategies in that few, if any, cross-licensing deals may be required to bring any given vaccine to market. This aspect is further discussed in Section 5 on the licensing status of the vaccines under development. The results of this “global access” FTO suggest that there are few major constraints related to patents that could complicate developing-country access to the vaccines under development. It should be noted that the analysis is limited to patent data and licensing information. Market considerations such as economies of scale, pricing and regulatory approval, or efficacy of the vaccine itself, are beyond its scope. Notwithstanding the relatively few patents applied for or issued in developing countries, an effective transfer of productive capacity of any of the vaccines to developing countries would require consideration of additional elements beyond patent data. Those include regulatory requirements, issues relating to know-how, and possible access to materials, such as cell lines. The report, nevertheless, identifies the state of product development, identifies key players, and the patent and licensing status, which together facilitate the development of effective strategies, including collaborations, as appropriate. These should enable early product deployment in areas where dengue most affects people’s lives and thus lead to accelerated access to dengue vaccines by those most in need. This report provides an informal guide for those wishing to better understand the important interplay of intellectual property (IP) with product development, manufacture and delivery (viz. access). It can be seen as an example of using patent information to address major global challenges, including access to medicines, and thus contribute to informed policy discussions, strategic research planning and technology transfer, and in that way, benefit humanity.

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World Intellectual Property Organization

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Invited contribution. Available at