Obstacles to vaccination of animals and prospective solutions.

On the 17th of October 2019, a workshop was held at Wageningen Bioveterinary Research in Lelystad, the Netherlands, to discuss the obstacles to vaccination in the veterinary field. Participants from academia, OIE, FAO, EC, EMA, USDA, national regulatory and veterinary health authorities, and the animal health industry discussed how availability and access to animal vaccines can be improved not just in the EU and US but also in Low to Middle Income Countries (LMIC) across the world and agreed that this requires innovations in both the scientific and the regulatory field. The workshop called for engaging all stakeholders to improve regulatory acceptance of novel vaccine technologies and encourage their registration. There is a need for better mutual understanding between academia, industry and regulators, and more openness to discuss framework, requirements, and product authorisations, and to converge the regulatory rules between regions. The next leap forward could be a broader application of novel technologies using RNA- or DNA-based vaccine platforms, where the "backbone" is maintained, while the gene of interest coding for an immunogenic protein can be exchanged in a standardised manner. This approach enables rapid response in outbreak situations and should lower the risk and cost of vaccine development.

Effectiveness and cost-effectiveness of vaccination against herpes zoster in Canada: a modelling study.

BACKGROUND: Two vaccines against herpes zoster are currently authorized for use in Canada: the recombinant subunit zoster vaccine and live attenuated zoster vaccine. We compared the effectiveness and cost-effectiveness of these 2 vaccines. METHODS: We used a decision analytic static cohort model parametrized with Canadian epidemiologic and economic data. We performed the economic analysis from the health care system perspective, using a lifetime horizon and a 3% discount rate for costs and benefits. The primary outcome was the incremental cost per quality-adjusted life-year (QALY) gained, relative to no vaccination. We ran 30 000 simulations varying all model parameters, including vaccine costs, efficacy and waning. RESULTS: The number needed to vaccinate (NNV) was higher for the live attenuated zoster vaccine than for the recombinant subunit zoster vaccine for all herpes zoster-related events at all ages. For example, in persons exactly 65 years old, for herpes zoster, median NNV was 21 (90% uncertainty interval [UI] 13-31) versus 8 (90% UI 6-18), and for postherpetic neuralgia, NNV was 64 (90% UI 33-93) versus 31 (90% UI 23-73). For the recombinant vaccine, the median cost-effectiveness ratios varied between cost-saving and $25 881 per QALY gained for adults aged 50 years or older. For the live vaccine, the cost-effectiveness ratios varied between cost-saving and $130 587 per QALY gained and were less than $45 000 per QALY gained only for those 65 to 75 years old. Given its higher efficacy, we estimated that the cost for the complete series of the recombinant vaccine could be $150 to $200 more than the cost of the live vaccine and still be considered cost-effective. INTERPRETATION: Our model predicted that the recombinant subunit zoster vaccine is likely cost-effective in Canada for adults 60 years or older, and is likely more cost-effective than live attenuated zoster vaccine. These results have informed updated national and provincial recommendations on herpes zoster vaccination.

Cost-effectiveness of Recombinant Zoster Vaccine (RZV) and Varicella Vaccine Live (VVL) against herpes zoster and post-herpetic neuralgia among adults aged 65 and over in Japan.

BACKGROUND: The approval of the extended use of 1-dose varicella vaccine (VVL) in adults aged 50 and older against herpes zoster (HZ) in 2016 and the 2-dose recombinant zoster vaccine (RZV) in 2018 raised the need to evaluate the value for money between these two vaccines. METHODS: We conducted a cost-effectiveness analysis with Markov modelling to evaluate the efficiency of the immunisation programmes from payer's perspective. Eight strategies with different ages to receive VVL or RZV were set, namely: 65-84 year old (y.o.), 70-84 y.o., 75-84 y.o., and 80-84 y.o. VVL- or RZV-strategy. Incremental cost-effectiveness ratios (ICERs) compared with curative care scenario were calculated. The health statuses following the target cohort were as follows: acute HZ followed by recovery, post-herpetic neuralgia followed by recovery, post HZ/PHN, recurrence of HZ, and general death. RESULTS: At the vaccination cost ¥8000 (US$73) for 1-dose ZVL and ¥30,000 (US$273) for 2-dose RZV, ICERs ranged from ¥2,633,587/US$23,942 (age 80-84 y.o.) to ¥3,434,267 or US$31,221 (age 65-84 y.o.)/QALY gained for VVL-strategies; from ¥5,262,227 or US$47,838 (age 80-84 y.o.) to ¥6,278,557 or US$57,078/QALY gained (age 65-84 y.o.) for RZV-strategies. Cost-effectiveness acceptability curves derived from probabilistic sensitivity analyses showed that if the cost-effective threshold was at ¥3,000,000 or US$27,273/QALY, the acceptability was 90.7% and 8.8% for 65-84 VVL-strategy and 65-84 RZV-strategy, respectively; if at ¥5,000,000 or US$45,455/QALY, 56.2% and 43.8%, and if at ¥10,000,000 or US$90,909/QALY 11.9% and 88.1%, respectively. CONCLUSION: Vaccinating individuals aged 65-84 y.o., 70-84 y.o., 75-84 y.o., 80-84 y.o. with VVL or RZV to prevent HZ-associated disease in Japan can be cost-effective from payer's perspective, with vaccination costs at ¥8,000 per shot for VVL, ¥30,000 for 2-dose RZV. While the results suggesting that only 65-84 VVL-strategy and 65-84 RZV strategy should be considered when introducing HZ immunisation programme. The optimal strategy varies depending on the willingness-to-pay threshold.

A Cost-Effectiveness Analysis of Vaccination for Prevention of Herpes Zoster and Related Complications: Input for National Recommendations.

Background: The U.S. Advisory Committee on Immunization Practices recently developed recommendations for use of a new recombinant zoster vaccine (RZV). Objective: To evaluate the cost-effectiveness of vaccination with RZV compared with zoster vaccine live (ZVL) and no vaccination, the cost-effectiveness of vaccination with RZV for persons who have previously received ZVL, and the cost-effectiveness of preferential vaccination with RZV over ZVL. Design: Simulation (state-transition) model using U.S. epidemiologic, clinical, and cost data. Data Sources: Published data. Target Population: Hypothetical cohort of immunocompetent U.S. adults aged 50 years or older. Time Horizon: Lifetime. Perspective: Societal and health care sector. Intervention: Vaccination with RZV (recommended 2-dose regimen), vaccination with ZVL, and no vaccination. Outcome Measures: The primary outcome measure was the incremental cost-effectiveness ratio (ICER). Results of Base-Case Analysis: For vaccination with RZV compared with no vaccination, ICERs ranged by age from $10 000 to $47 000 per quality-adjusted life-year (QALY), using a societal perspective and assuming 100% completion of the 2-dose RZV regimen. For persons aged 60 years or older, ICERs were less than $60 000 per QALY. Vaccination with ZVL was dominated by vaccination with RZV for all age groups 60 years or older. Results of Sensitivity Analysis: Results were most sensitive to changes in vaccine effectiveness, duration of protection, herpes zoster incidence, and probability of postherpetic neuralgia. Vaccination with RZV after previous administration of ZVL yielded an ICER of less than $60 000 per QALY for persons aged 60 years or older. In probabilistic sensitivity analyses, RZV remained the preferred strategy in at least 95% of simulations, including those with 50% completion of the second dose. Limitation: Few data were available on risk for serious adverse events, adherence to the recommended 2-dose regimen, and probability of recurrent zoster. Conclusion: Vaccination with RZV yields cost-effectiveness ratios lower than those for many recommended adult vaccines, including ZVL. Results are robust over a wide range of plausible values. Primary Funding Source: Centers for Disease Control and Prevention.

Cost-effectiveness of an adjuvanted recombinant zoster vaccine in older adults in the United States who have been previously vaccinated with zoster vaccine live.

Zoster Vaccine Live (ZVL) is marketed in the US since 2008, and a non-live adjuvanted Recombinant Zoster Vaccine (RZV) was approved in 2017. Literature suggests that waning of ZVL efficacy may necessitate additional vaccination. The Advisory Committee on Immunization Practices recommended vaccination with RZV in immunocompetent adults aged 50+ years old, including those previously vaccinated with ZVL. The objective of this study was to determine the cost-effectiveness of vaccinating US adults aged 60+ years old, previously vaccinated with ZVL. The ZOster ecoNomic Analysis (ZONA) model, a deterministic Markov model, was adapted to follow a hypothetical 1 million(M)-person cohort of US adults previously vaccinated with ZVL. Model inputs included demographics, epidemiology, vaccine characteristics, utilities and costs. Costs and quality-adjusted life-years (QALYs) were presented over the lifetimes of the cohort from the year of additional vaccination, discounted 3% annually. The model estimated that, vaccination with RZV 5 years after previous vaccination with ZVL, would reduce disease burden compared with no additional vaccination, resulting in a gain of 1,633 QALYs at a total societal cost of $96M (incremental cost-effectiveness ratio: $58,793/QALY saved). Compared with revaccinating with ZVL, vaccination with RZV would result in a gain of 1,187 QALYs and societal cost savings of almost $84M. Sensitivity, scenario, and threshold analyses demonstrated robustness of these findings. Vaccination with RZV is predicted to be cost-effective relative to no additional vaccination, assuming a threshold of $100,000/QALY, and cost-saving relative to ZVL revaccination of US adults aged 60+ years old who have been previously vaccinated with ZVL.

Cost-effectiveness of the recombinant zoster vaccine in the German population aged ≥60 years old.

Each year, around 300,000 Herpes Zoster (HZ) cases are observed in the German population, resulting in costs over €182 million to society. The objective of this study was to estimate the potential public health and economic impact of the new Adjuvanted Recombinant Zoster Vaccine (RZV, Shingrix) in the German population ≥ 60 years of age (YOA) and to identify the optimal age of vaccination. We used a static, multi-cohort Markov model that followed a hypothetical cohort of 1 million people ≥ 60 YOA life-long after vaccination using German-specific inputs. Both costs and outcomes were discounted at 3%, the incremental cost-effectiveness ratio (ICER) was calculated based on the societal perspective. The coverage of RZV was set at 40% with a second-dose compliance of 70%. Vaccinating the population aged ≥ 60 YOA would result in 45,000 HZ cases avoided, 1,713 quality-adjusted life years (QALYs) gained at a total cost of approximately €63 million compared to 38,000 cases avoided, 1,545 QALYs gained at a total cost of approximately €68 million in the population ≥ 70 YOA. This would result in an ICER of approximately €37,000 and €44,000/QALY, for the age cohort ≥ 60 and ≥ 70 YOA, respectively. Scenario analyses demonstrated that vaccinating at age 60 or 65 YOA would show greater public health impact and would result in the lowest observed ICER compared to vaccinating at 70 YOA. In conclusion, starting vaccination with RZV in the German population ≥ 60 YOA would demonstrate the best value from a public health and economic standpoint.

A simian-adenovirus-vectored rabies vaccine suitable for thermostabilisation and clinical development for low-cost single-dose pre-exposure prophylaxis.

BACKGROUND: Estimates of current global rabies mortality range from 26,000 to 59,000 deaths per annum. Although pre-exposure prophylaxis using inactivated rabies virus vaccines (IRVs) is effective, it requires two to three doses and is regarded as being too expensive and impractical for inclusion in routine childhood immunization programmes. METHODOLOGY/ PRINCIPAL FINDINGS: Here we report the development of a simian-adenovirus-vectored rabies vaccine intended to enable cost-effective population-wide pre-exposure prophylaxis against rabies. ChAdOx2 RabG uses the chimpanzee adenovirus serotype 68 (AdC68) backbone previously shown to achieve pre-exposure protection against rabies in non-human primates. ChAdOx2 differs from AdC68 in that it contains the human adenovirus serotype 5 (AdHu5) E4 orf6/7 region in place of the AdC68 equivalents, enhancing ease of manufacturing in cell lines which provide AdHu5 E1 proteins in trans. We show that immunogenicity of ChAdOx2 RabG in mice is comparable to that of AdC68 RabG and other adenovirus serotypes expressing rabies virus glycoprotein. High titers of rabies virus neutralizing antibody (VNA) are elicited after a single dose. The relationship between levels of VNA activity and rabies virus glycoprotein monomer-binding antibody differs after immunization with adenovirus-vectored vaccines and IRV vaccines, suggesting routes to further enhancement of the efficacy of the adenovirus-vectored candidates. We also demonstrate that ChAdOx2 RabG can be thermostabilised using a low-cost method suitable for clinical bio-manufacture and ambient-temperature distribution in tropical climates. Finally, we show that a dose-sparing effect can be achieved by formulating ChAdOx2 RabG with a simple chemical adjuvant. This approach could lower the cost of ChAdOx2 RabG and other adenovirus-vectored vaccines. CONCLUSIONS/ SIGNIFICANCE: ChAdOx2 RabG may prove to be a useful tool to reduce the human rabies death toll. We have secured funding for Good Manufacturing Practice- compliant bio-manufacture and Phase I clinical trial of this candidate.

Production and efficacy of a low-cost recombinant pneumococcal protein polysaccharide conjugate vaccine.

Streptococcus pneumoniae is the leading cause of bacterial pneumonia. Although this is a vaccine preventable disease, S. pneumoniae still causes over 1 million deaths per year, mainly in children under the age of five. The biggest disease burden is in the developing world, which is mainly due to unavailability of vaccines due to their high costs. Protein polysaccharide conjugate vaccines are given routinely in the developed world to children to induce a protective antibody response against S. pneumoniae. One of these vaccines is Prevnar13, which targets 13 of the 95 known capsular types. Current vaccine production requires growth of large amounts of the 13 serotypes, and isolation of the capsular polysaccharide that is then chemically coupled to a protein, such as the diphtheria toxoid CRM197, in a multistep expensive procedure. In this study, we design, purify and produce novel recombinant pneumococcal protein polysaccharide conjugate vaccines in Escherichia coli, which act as mini factories for the low-cost production of conjugate vaccines. Recombinant vaccine efficacy was tested in a murine model of pneumococcal pneumonia; ability to protect against invasive disease was compared to that of Prevnar13. This study provides the first proof of principle that protein polysaccharide conjugate vaccines produced in E. coli can be used to prevent pneumococcal infection. Vaccines produced in this manner may provide a low-cost alternative to the current vaccine production methodology.

Establishment of a yeast-based VLP platform for antigen presentation.

BACKGROUND: Chimeric virus-like particles (VLP) allow the display of foreign antigens on their surface and have proved valuable in the development of safe subunit vaccines or drug delivery. However, finding an inexpensive production system and a VLP scaffold that allows stable incorporation of diverse, large foreign antigens are major challenges in this field. RESULTS: In this study, a versatile and cost-effective platform for chimeric VLP development was established. The membrane integral small surface protein (dS) of the duck hepatitis B virus was chosen as VLP scaffold and the industrially applied and safe yeast Hansenula polymorpha (syn. Pichia angusta, Ogataea polymorpha) as the heterologous expression host. Eight different, large molecular weight antigens of up to 412 amino acids derived from four animal-infecting viruses were genetically fused to the dS and recombinant production strains were isolated. In all cases, the fusion protein was well expressed and upon co-production with dS, chimeric VLP containing both proteins could be generated. Purification was accomplished by a downstream process adapted from the production of a recombinant hepatitis B VLP vaccine. Chimeric VLP were up to 95% pure on protein level and contained up to 33% fusion protein. Immunological data supported surface exposure of the foreign antigens on the native VLP. Approximately 40 mg of chimeric VLP per 100 g dry cell weight could be isolated. This is highly comparable to values reported for the optimized production of human hepatitis B VLP. Purified chimeric VLP were shown to be essentially stable for 6 months at 4 °C. CONCLUSIONS: The dS-based VLP scaffold tolerates the incorporation of a variety of large molecular weight foreign protein sequences. It is applicable for the display of highly immunogenic antigens originating from a variety of pathogens. The yeast-based production system allows cost-effective production that is not limited to small-scale fundamental research. Thus, the dS-based VLP platform is highly efficient for antigen presentation and should be considered in the development of future vaccines.

A novel immunization approach for dengue infection based on conserved T cell epitopes formulated in calcium phosphate nanoparticles.

Dengue virus (DV) is the etiologic agent of dengue fever, the most significant mosquito-borne viral disease in humans. Most DV vaccine approaches are focused on generating antibody mediated responses; one such DV vaccine is approved for use in humans but its efficacy is limited. While it is clear that T cell responses play important role in DV infection and subsequent disease manifestations, fewer studies are aimed at developing vaccines that induce robust T cells responses. Potent T cell based vaccines require 2 critical components: the identification of specific T cell stimulating MHC associated peptides, and an optimized vaccine delivery vehicle capable of simultaneously delivering the antigens and any required adjuvants. We have previously identified and characterized DV specific HLA-A2 and -A24 binding DV serotypes conserved epitopes, and the feasibility of an epitope based vaccine for DV infection. In this study, we build on those previous studies and describe an investigational DV vaccine using T cell epitopes incorporated into a calcium phosphate nanoparticle (CaPNP) delivery system. This study presents a comprehensive analysis of functional immunogenicity of DV CaPNP/multipeptide formulations in vitro and in vivo and demonstrates the CaPNP/multipeptide vaccine is capable of inducing T cell responses against all 4 serotypes of DV. This synthetic vaccine is also cost effective, straightforward to manufacture, and stable at room temperature in a lyophilized form. This formulation may serve as an effective candidate DV vaccine that protects against all 4 serotypes as either a prophylactic or therapeutic vaccine.

Country specific predictions of the cost-effectiveness of malaria vaccine RTS,S/AS01 in endemic Africa.

BACKGROUND: RTS,S/AS01 is a safe and moderately efficacious vaccine considered for implementation in endemic Africa. Model predictions of impact and cost-effectiveness of this new intervention could aid in country adoption decisions. METHODS: The impact of RTS,S was assessed in 43 countries using an ensemble of models of Plasmodium falciparum epidemiology. Informed by the 32months follow-up data from the phase 3 trial, vaccine effectiveness was evaluated at country levels of malaria parasite prevalence, coverage of control interventions and immunization. Benefits and costs of the program incremental to routine malaria control were evaluated for a four dose schedule: first dose administered at six months, second and third - before 9months, and fourth dose at 27months of age. Sensitivity analyses around vaccine properties, transmission, and economic inputs were conducted. RESULTS: If implemented in all 43 countries the vaccine has the potential to avert 123 (117;129) million malaria episodes over the first 10years. Burden averted averages 18,413 (range of country median estimates 156-40,054) DALYs per 100,000 fully vaccinated children with much variation across settings primarily driven by differences in transmission intensity. At a price of $5 per dose program costs average $39.8 per fully vaccinated child with a median cost-effectiveness ratio of $188 (range $78-$22,448) per DALY averted; the ratio is lower by one third - $136 (range $116-$220) - in settings where parasite prevalence in children aged 2-10years is at or above 10%. CONCLUSION: RTS,S/AS01has the potential to substantially reduce malaria burden in children across Africa. Conditional on assumptions on price, coverage, and vaccine properties, adding RTS,S to routine malaria control interventions would be highly cost-effective. Implementation decisions will need to further consider feasibility of scaling up existing control programs, and operational constraints in reaching children at risk with the schedule.

The Long-Term Safety, Public Health Impact, and Cost-Effectiveness of Routine Vaccination with a Recombinant, Live-Attenuated Dengue Vaccine (Dengvaxia): A Model Comparison Study.

BACKGROUND: Large Phase III trials across Asia and Latin America have recently demonstrated the efficacy of a recombinant, live-attenuated dengue vaccine (Dengvaxia) over the first 25 mo following vaccination. Subsequent data collected in the longer-term follow-up phase, however, have raised concerns about a potential increase in hospitalization risk of subsequent dengue infections, in particular among young, dengue-naïve vaccinees. We here report predictions from eight independent modelling groups on the long-term safety, public health impact, and cost-effectiveness of routine vaccination with Dengvaxia in a range of transmission settings, as characterised by seroprevalence levels among 9-y-olds (SP9). These predictions were conducted for the World Health Organization to inform their recommendations on optimal use of this vaccine. METHODS AND FINDINGS: The models adopted, with small variations, a parsimonious vaccine mode of action that was able to reproduce quantitative features of the observed trial data. The adopted mode of action assumed that vaccination, similarly to natural infection, induces transient, heterologous protection and, further, establishes a long-lasting immunogenic memory, which determines disease severity of subsequent infections. The default vaccination policy considered was routine vaccination of 9-y-old children in a three-dose schedule at 80% coverage. The outcomes examined were the impact of vaccination on infections, symptomatic dengue, hospitalised dengue, deaths, and cost-effectiveness over a 30-y postvaccination period. Case definitions were chosen in accordance with the Phase III trials. All models predicted that in settings with moderate to high dengue endemicity (SP9 ≥ 50%), the default vaccination policy would reduce the burden of dengue disease for the population by 6%-25% (all simulations: -3%-34%) and in high-transmission settings (SP9 ≥ 70%) by 13%-25% (all simulations: 10%- 34%). These endemicity levels are representative of the participating sites in both Phase III trials. In contrast, in settings with low transmission intensity (SP9 ≤ 30%), the models predicted that vaccination could lead to a substantial increase in hospitalisation because of dengue. Modelling reduced vaccine coverage or the addition of catch-up campaigns showed that the impact of vaccination scaled approximately linearly with the number of people vaccinated. In assessing the optimal age of vaccination, we found that targeting older children could increase the net benefit of vaccination in settings with moderate transmission intensity (SP9 = 50%). Overall, vaccination was predicted to be potentially cost-effective in most endemic settings if priced competitively. The results are based on the assumption that the vaccine acts similarly to natural infection. This assumption is consistent with the available trial results but cannot be directly validated in the absence of additional data. Furthermore, uncertainties remain regarding the level of protection provided against disease versus infection and the rate at which vaccine-induced protection declines. CONCLUSIONS: Dengvaxia has the potential to reduce the burden of dengue disease in areas of moderate to high dengue endemicity. However, the potential risks of vaccination in areas with limited exposure to dengue as well as the local costs and benefits of routine vaccination are important considerations for the inclusion of Dengvaxia into existing immunisation programmes. These results were important inputs into WHO global policy for use of this licensed dengue vaccine.

The Future of the RTS,S/AS01 Malaria Vaccine: An Alternative Development Plan.

Roly Gosling and Lorenz von Seidlein consider a potential future development plan for the RTS,S/AS01 malaria vaccine.

Costing RTS,S introduction in Burkina Faso, Ghana, Kenya, Senegal, Tanzania, and Uganda: A generalizable approach drawing on publicly available data.

Recent results from the phase 3 trial of RTS,S/AS01 malaria vaccine show that the vaccine induced partial protection against clinical malaria in infants and children; given the high burden of the disease it is currently considered for use in malaria endemic countries. To inform adoption decisions the paper proposes a generalizable methodology to estimate the cost of vaccine introduction using routinely collected and publicly available data from the cMYP, UNICEF, and WHO-CHOICE. Costing is carried out around a set of generic activities, assumptions, and inputs for delivery of immunization services adapted to a given country and deployment modality to capture among other factors the structure of the EPI program, distribution model, geography, and demographics particular to the setting. The methodology is applied to estimate the cost of RTS,S introduction in Burkina Faso, Ghana, Kenya, Senegal, Tanzania, and Uganda. At an assumed vaccine price of $5 per dose and given our assumptions on coverage and deployment strategy, we estimate total economic program costs for a 6-9 months cohort within $23.11-$28.28 per fully vaccinated child across the 6 countries. Net of procurement, costs at country level are substantial; for instance in Tanzania these could add as much as $4.2 million per year or an additional $2.4 per infant depending on the level of spare capacity in the system. Differences in cost of vaccine introduction across countries are primarily driven by differences in cost of labour. Overall estimates generated with the methodology result in costs within the ranges reported for other new vaccines introduced in SSA and capture multiple sources of heterogeneity in costs across countries. Further validation with data from field trials will support use of the methodology while also serving as a validation for cMYP and WHO-CHOICE as resources for costing health interventions in the region.

RTS,S: Toward a first landmark on the Malaria Vaccine Technology Roadmap.

The Malaria Vaccine Technology Roadmap calls for a 2015 landmark goal of a first-generation malaria vaccine that has protective efficacy against severe disease and death, lasting longer than one year. This review focuses on product development efforts over the last five years of RTS,S, a pre-erythrocytic, recombinant subunit, adjuvanted, candidate malaria vaccine designed with this goal of a first-generation malaria vaccine in mind. RTS,S recently completed a successful pivotal Phase III safety, efficacy and immunogenicity study. Although vaccine efficacy was found to be modest, a substantial number of cases of clinical malaria were averted over a 3-4 years period, particularly in settings of significant disease burden. European regulators have subsequently adopted a positive opinion under the Article 58 procedure for an indication of active immunization of children aged 6 weeks up to 17 months against malaria caused by Plasmodium falciparum and against hepatitis B. Further evaluations of the benefit, risk, feasibility and cost-effectiveness of RTS,S are now anticipated through policy and financing reviews at the global and national levels.

Bringing plant-based veterinary vaccines to market: Managing regulatory and commercial hurdles.

The production of recombinant vaccines in plants may help to reduce the burden of veterinary diseases, which cause major economic losses and in some cases can affect human health. While there is abundant research in this area, a knowledge gap exists between the ability to create and evaluate plant-based products in the laboratory, and the ability to take these products on a path to commercialization. The current report, arising from a workshop sponsored by an Organisation for Economic Co-operation and Development (OECD) Co-operative Research Programme, addresses this gap by providing guidance in planning for the commercialization of plant-made vaccines for animal use. It includes relevant information on developing business plans, assessing market opportunities, manufacturing scale-up, financing, protecting and using intellectual property, and regulatory approval with a focus on Canadian regulations.