(2009), see Table 2. However, official reported cases of dengue under-estimate the number of clinical cases of the disease (discussed by Suaya et al., 2009), so the global economic burden of dengue reported based on reported cases is conservative. Therefore, we adjusted the global caseload and economic burden upwards
by a factor of 6, to account for unreported cases Selleckchem Epigenetics Compound Library (Armien et al., 2008). The same assumptions regarding dengue case loads and adjustments for unreported cases were also made for the vaccine impact model (next Section). Our estimates for global clinical case load, economic burden, and weighted average cost per case are presented in Table 3 (top three rows). A dengue drug will have clinical utility if the availability and market penetration of dengue vaccines is insufficient to eliminate transmission of dengue. We constructed a Monte Carlo Simulation model (10,000 simulations) using Oracle Crystal Ball®
to project future dengue case loads based on current trends and publicly available information about dengue vaccines. The key assumptions of the model including distributions, most likely, minimum and maximum values are summarized in Table 4. Generally we have assumed a normal distribution, with a standard deviation of 10% around the most likely value, except where there was specific information from the literature that suggested an alternative distribution might be appropriate. More details regarding some of the assumptions are outlined below. Sanofi’s tetravalent dengue vaccine is in Phase III trials. We selected a probability of successful completion of Sorafenib in vivo the Phase
III program and licensure at 75% based on our perception of industry norms for a typical biotech product. A launch of date Inositol monophosphatase 1 of 2015 is feasible if there are no delays in Sanofi’s development program. Inviragen, GSK, and Merck all have dengue vaccines in development, and NIH, has licensed its technology to four institutions or companies regionally. These other efforts appear to be in late Phase I or early Phase II, and so could in theory be licensed in a 2017–2021 time window if development plans remain on track. Therefore, we selected the most likely licensure date as 2019, with minimum and maximum ranges of 2017 and 2021. We have assumed that the probability of achieving licensure for each of these vaccines is approximately 21% (35% probability of success in Phase II × 60% probability of success in Phase III) based on industry norms for a typical biotech product in early clinical development (Zemmel and Shiekh, 2010). The probability of discrete numbers (0–7) of additional vaccines being approved was then calculated. We have assumed that the volume of dengue vaccine doses sold will be limited by capacity, and that the price of dengue vaccines that is negotiated will be set in a manner that will allow the available capacity to be sold.