An Alternative Vision for the Boston University National Emerging Infectious Diseases Laboratory
Stop the Biolab Coalition, July 19, 2010
Marginal value of Boston University’s present focus
There are two major shortcomings of the Boston University (BU) National Emerging Infectious Diseases Laboratory (NEIDL) plan. First, the proposed research on bioweapons agents is redundant because there are laboratories throughout the nation already engaged in this research. Second, the focus on emerging infectious disease has minimal value compared to research on other kind of infectious disease. The NEIDL would better serve public health if it conducted research on prevalent natural infectious diseases and safe technologies rather than its current focus on bioweapons pathogens that require Biosafety Laboratory Level-4 (BSL4). This paper sets forth such an alternative vision.
Although Boston University tries to downplay biodefense research, it would be obligated to carry out biodefense research requested by the National Institutes of Health (NIH). That obligation flows from the fact that the National Institutes of Health funded the construction of the NEIDL facility. The focus on biodefense is evident when one examines the list of organisms that will be studied in the NEIDL. Although BU has been reluctant to identify the specific pathogens that will be studied despite many requests for this information, it has recently listed “some of the organisms that will be studied.” Five of the seven identified pathogens are Category A bioweapons agents. This high percentage of bioweapons agents contradicts any claim that its focus is emerging infectious disease. Our Alternative Vision, to the contrary, details a different kind of research. There would be no need to work on the highly dangerous live BSL4 pathogens that BU proposes for the NEIDL and no need to divert public health dollars into biodefense.
We challenge the utility of Boston University’s planned biodefense-related research. Other laboratories are already researching and developing countermeasures for all the major bioweapons agents. This focus on BSL4 bioweapons agents is evident in the large and growing number of bioweapons-related research publications that have appeared since 2002. We, therefore, question what the BU NEIDL can add at this late stage.
We also question the value of conducting research into so-called emerging infectious diseases. The term “emerging infectious diseases” has been applied by Boston University to BSL4 bioweapons agents such as the hemorrhagic fever viruses Ebola, Marburg and Lassa. The term is misleading as it implies a public health urgency that these pathogens do not deserve. They, in fact, present no public health threat in the United States and only a minor health threat anywhere else. Their public health importance pales next to the pathogens responsible for diarrheal, respiratory, and sexually transmitted disease. In fact, the rare BSL4 pathogens should be rightfully classified as “exotic,” not emerging. Only one pathogen out of seven on BU’s list, Mycobacterium tuberculosis, is a bona fide public health threat in the US and in most other parts of the world.
In sum, anticipated research on BSL4 pathogens in the Boston University NEIDL has marginal public health and marginal biodefense value. An alternative focus and cost-effective strategy for NEIDL is clearly needed and easily attainable. Such a strategy, we maintain, should focus on employing and developing new technologies that seek to prevent and cure infectious diseases of substantial public health concern.
An alternative vision
By refocusing its research on prevalent natural disease and by adopting new, safe vaccine and antimicrobial technologies, Boston University could make a major contribution to public health without the hazards of working with dangerous pathogens that require BSL4 laboratories. With a focus on prevalent natural diseases as opposed to rare and exotic ones, the possible escape of pathogens from the lab would have less consequence since those organisms would already be present in the community.
In particular, Boston University should consider countermeasures against prevalent pathogens such as Staphylococcus aureus, Clostridium difficile, Streptococcus pneumoniae, Pseudomonas aeruginosa, Acinetobacter baumannii and Chlamydia trachomatis, for which US death rates are high and rising, and for which many strains are now resistant to most or all antibiotics. These genuinely “reemerging” bacterial diseases represent a grave public health threat because of growing antibiotic-resistance. The World Health Organization has identified antibiotic resistance as one of the greatest threats to human health.
Boston University NEIDL funding could also be more wisely spent on countermeasures for viruses responsible for respiratory infections, diarrheal diseases, and sexually transmitted diseases that are major public health threats everywhere, and for those truly emerging viruses such as West Nile and dengue.
New vaccine technologies employ pathogen mimics that cannot cause infection or disease. As such, they pose no risk to laboratory workers or to the communities surrounding the laboratory. Most research and development of vaccines using the new technologies may be carried out in BSL1 and BSL2 laboratories since special precautions are not needed.
An even more fundamental criticism of the proposed NEIDL research is that vaccines are not the best approach for defense against a bioweapons attack. Vaccines require a few weeks and often several inoculations in order to establish protection. They have some unavoidable drawbacks such as short shelf life and inability to demonstrate efficacy for bioweapons vaccines. Vaccines against prevalent diseases generally avoid such drawbacks as there are ample human subjects to demonstrate efficacy. Moreover, since the vaccines are in continual use, shelf life is usually not a problem. Vaccines against bioweapons agents and rare diseases are a “one bug, one drug” approach, as they target only one pathogen and sometimes only one strain of a pathogen. Witness the need for new vaccines each year for the annual flu.
While some of the new vaccine technologies can produce safer vaccines faster than traditional vaccine manufacture, an emphasis on oral antiviral and antibacterial drugs would provide a broader and more rapidly deployed defense since they would not require injections. Broad-spectrum antibiotics and antivirals developed to target prevalent natural diseases have immediate application to biodefense as well. The broad-spectrum approach is indeed a way to meet both public health and biodefense needs simultaneously. There is a pressing need for inexpensive new antivirals and antibiotics which are small-molecule, broad-spectrum, and orally available to counter natural disease and for biodefense purposes.
The Boston University NEIDL seems to be hiring staff with expertise on viruses and on immunology for vaccine development. If, as we have suggested, BU would instead turn some of its attention to finding new approaches for small-molecule antivirals and antibiotics, it would then need to bring in expertise to the NEIDL that it may not now have, in particular in the areas of medicinal chemistry and rapid screening of drug candidates. A significant medicinal chemistry and screening capability added to the NEIDL would also serve the Boston-area infectious disease research community, as both are in short supply. BU should also consider making its Good Laboratory Practice, pilot manufacturing, and clinical trial expertise available to academic labs and small biotechnology companies that are currently developing new infectious-disease drugs.
If Boston University does remain focused on biodefense vaccines
If Boston University redirected its efforts towards devising rapid vaccine development platforms and manufacturing methodologies for seasonal and pandemic influenza, it would assure the relevance of the NEIDL to both pressing public health needs and to its required biodefense mission. From this perspective, the National Institutes of Allergy and Infectious Disease (NIAID) may be amenable to changing NEIDL’s mission away from “one bug, one drug” goals. Given NIAID’s own refocus on broad-spectrum approaches, it might be willing to turn the NEIDL toward similar broad-spectrum countermeasures and vaccine-platform development.
Efficacy demonstration for vaccines against prevalent pathogens would eventually require clinical trials in humans. In this regard, BU already has plans to carry vaccines and other countermeasures through phase I safety clinical trials and thus will have in place the Good Laboratory Practice and small-scale manufacturing necessary for FDA approval. NEIDL might consider extending this expertise to managing Phase II and Phase III clinical trials. This would provide a much needed service. For promising new vaccines or drugs, special consideration should be given to allowing residents of the surrounding communities to participate in clinical trials.
The full report, which follows, provides documentation for the ideas and assertions made in this summary.
An Alternative Vision for the Boston University National Emerging Infectious Diseases Laboratory
Protecting public health
We are proposing an alternative vision for the National Emerging Infectious Diseases Laboratory that will be operated by Boston University. Our alternative vision involves much less risk and much more benefit to the public than the current research plan. Since our vision does not involve research on any of the live Biosafety level 4 (BSL4) pathogens slated for use in this laboratory, we would not require this highest level of containment.
In short, there are alternative strategies for the Boston University (BU) National Emerging Infectious Diseases Laboratory (NEIDL) facility. Those strategies would better serve the most pressing public health efforts against natural infectious disease. To the extent that Boston University has made its intentions known, its research plan for the NEIDL will not serve the public health needs of either Boston or the nation as a whole. To the contrary, the alternative strategies discussed here would serve both Boston University’s emerging infectious disease and biodefense purposes. This report suggests replacing NEIDL’s current focus with a much safer way to add value to public health dollars. This alternative strategy emphasizes the safety of our neighboring communities.
There are a number of hazardous activities that are extremely worrisome if housed or researched in the city of Boston, regardless of the level of biocontainment:
Highly contagious pathogens absent or near absent from the natural world (such as virulent forms of the 1918 pandemic influenza virus and SARS)
Deadly pathogens not endemic to the United States for which there is no cure or prevention (such as virulent forms of Ebola, Marburg and Lassa viruses)
Weaponized forms of virulent biological weapons agents (such as aerosolized forms of Bacillus anthracis)
Aerosol studies on virulent pathogen strains (since aerosols are an efficient means of infecting many people at one time)
The risk of loss of containment of deadly microbial agents that are released either by accident or by malicious design is multiplied substantially in a crowded urban environment where many more people can be exposed to and spread disease.
Concerns over NEIDL’s current focus
The current research focus of the NEIDL is emerging infectious disease and biodefense. While BU tries to downplay its biodefense research plans, it is in fact obligated to carry out biodefense research at the bidding of NIH. This obligation is memorialized in a commitment letter dated January 28, 2003, which states that “the [NEIDL] facility would be devoted exclusively to biodefense research and other NIAID-defined research programs for 20 years.” A copy of this commitment letter is provided in Appendix I.
Historically, BU has been less than transparent regarding the pathogens that will be studied in its NEIDL facility. Recently, however, the NEIDL website recently identified “some of the organisms that will be studied.” A summary of reported fatalities and the geographic distribution for the identified organisms are presented in Table 1.
Table 1. Some pathogens BU claims that it will study to develop vaccines and other countermeasures
MDR stands for multiple drug resistant. The table was compiled from data on the CDC’s Special Pathogens web site (http://www.cdc.gov/ncidod/dvrd/spb/index.htm) and other sources. See Appendix II for specific references.
Lacking a complete list of pathogens identified for study at the NEIDL, we assume that the Table 1 list is representative. Of the seven listed agents that BU is planning to study, five represent almost all the Category A bioweapons agents. The five Category A agents are listed below with diseases in parentheses.
Ebola virus (viral hemorrhagic fever)
Marburg virus (viral hemorrhagic fever)
Lassa virus (viral hemorrhagic fever)
Francisella tularensis (tularemia, rabbit fever)
Yersinia pestis (plague)
In BU’s 2003 grant application to NIH requesting funding for the NEIDL (BAA-NIH-NIAID-NCRR-DMID-03-36 these same bioweapons agents made up 19 of the 24 planned research projects that BU proposes to conduct in its lab. The remaining 6 projects would focus broadly on category A/B pathogens (which also include the 5 bioweapons listed above) and botulinum toxin, yet another category A bioweapon.
Therefore, all of BU's proposed research programs would focus on bioweapons agents.
This contradicts BU’s claim that its focus is emerging infectious disease, not bioweapons agents.
Indeed, the term “emerging infectious diseases” is misleading as it implies an importance that these pathogens do not deserve. All of these pathogens have been known for many years. None causes more than a few deaths in the United States in any year. Except for Mycobacterium tuberculosis, the small worldwide disease fatalities caused by the Table 1 pathogens and toxins compared to other diseases, and the fact that fatalities and geographic distribution are not increasing over time (see Appendix II), indicate that they should be classified as rare or exotic diseases, not emerging ones.
Compare their fatalities to the world-wide death toll from AIDS (over 2 million), respiratory infections (over 4 million), diarrheal diseases (over 2 million), and sexually transmitted diseases excluding AIDS (128,000), all of which are serious public health problems in the United States as well as worldwide. There is concern that some of these diseases - for example, Lassa fever - are significantly underreported in Africa. Lassa does not represent a public health threat in the United States. The fact that it is underreported does not qualify it as an emerging disease. In any event, live Lassa virus should not be housed or researched in the BU NEIDL. As befitting its danger, it would require BSL4 containment.
What about defense against bioterrorism?
“To put this in perspective, since 2000 bioterrorism has killed 5 Americans. In the same time period, influenza-related deaths alone have likely exceeded 300,000 based on CDC estimates, and other natural infectious diseases have killed hundreds of thousands more. Annual US morbidity & mortality figures from AIDS (14,000 deaths), opportunistic infections such as MRSA (19,000 deaths/year) and C. difficile (350,000 infections and up to 20,000 deaths) speak to unmet and pressing public health need. Consequently the threat of bioterrorism, which does exist but which is almost certainly minor, needs to be seen as only one element in the wider and larger public health war on infectious diseases.”
Furthermore, the current plan for the NEIDL would require the use of viral genomes on plasmid vectors. While a few genes for proteins of interest on plasmids for countermeasure development are necessary, we question the wisdom of propagating viral genomes engineered into plasmid vectors. This would make category A pathogens easily portable. Unregulated expansion of this capability will further democratize bioweapons capability, decreasing biosecurity.
For comparison with Table 1, yearly fatalities caused by some bacterial pathogens and seasonal flu that are major public health threats are presented in Table 2. The data in these tables were gathered by the CDC several years ago, and fatalities for the bacterial pathogens are increasing due to increasing resistance to antibiotics. For instance, the number of fatalities from Staphylococcus aureus in 2007 was thought to be about 19,000. The World Health Organization has identified antibiotic resistance as one of the greatest threats to human health.
Table 2. Centers for Disease Control estimates of fatalities caused by pathogens of major concern from growing antibiotic resistance.
The scientific community has very little interest in most of the BU NEIDL Table 1 pathogens except insofar as they are bioweapons agents, an aspect already being addressed in other laboratories. Instead, most infectious-disease research interest is focused on emerging antibiotic-resistant pathogens such as drug resistant staph (MRSA).
One way to gauge whether the scientific community has responded to concern over bioweapons agents is to look at the numbers of scientific publication citations in Pub Med, which lists nearly all publications in medicine throughout the world. The numbers of scientific publications that mention the pathogens planned for the NEIDL over two time periods, 1992-1999 and 2002-2009 are presented in Table 3.
Table 3. Pub Med citations and biosafety level for the BU NEIDL pathogens
The search terms used were the formal names of the pathogens, since these were more likely to generate lists of actual scientific publications compared to using, for example, the disease names. Pub Med was accessed between March 13 and 15, 2010.
There is a large increase in publications, 113%, between the time periods 1992 - 1999 and 2002 – 2009 for the NEIDL pathogens. If Mycobacterium tuberculosis and KFD virus are eliminated from the list, the increase in publications for the Category A bioweapons agents is a whopping 227%. Thus, the pathogens of concern for biodefense are being actively researched in many laboratories (see below and footnote 9). BU is late in the game; therefore, we question what the BU NEIDL can add at this juncture.
The 227% increase in publications is due to the billions of dollars that have been poured into biodefense since the anthrax letters of 2001. This reinforces the idea that the billions in research funding for biodefense may redirect research away from infectious disease of public health concern.
All the pathogens requiring BSL4 containment are responsible for only a few fatalities worldwide compared to major public health threats and almost no fatalities in the United States (Table 1). The hundreds of millions of dollars to build, maintain, and carry out research on the BU NEIDL pathogens over the years has little public health or added biodefense value. An alternative, cost-effective strategy and focus for NEIDL are clearly needed. Such a strategy, we maintain, should focus on preventatives and cures for natural infectious diseases of substantial public health concern.
An alternative vision
By adopting new, safe vaccine and antimicrobial technologies and refocusing its research and development to natural disease, BU can make a major contribution to public health without the public safety dangers of working with virulent pathogens that require BSL4 laboratories.
A BSL3/BSL4 service facility
For particularly virulent or highly contagious pathogens not prevalent in the US, a BSL4 laboratory would only be required for short periods of time, only at the beginning (e.g. isolation and cloning of genes from recently isolated live pathogens) and end of projects (e.g. studying the efficacy of drugs and vaccines in challenge experiments in animals). For the time being, these beginning and end procedures can be carried out in other BSL4 labs already working with these pathogens.
But there is a better way, which is safer for the communities that already house BSL3 and BSL4 laboratories. A large BSL3/BSL4 service facility should be created whose sole function is testing countermeasures against live deadly pathogens on behalf of researchers developing them elsewhere. The facility should be located far from any population center, in the desert or on an uninhabited coastal island for example. In addition to the physical barriers, for added insurance those who research highly contagious pathogens would work in days-long stints and then remain in quarantine for a short period afterward. This would cover multiple risks that are currently unattended, such as working on the live 1918 pandemic flu virus that killed 40 million people around the world and could potentially do it again if accidentally reintroduced. Against the chance of an outbreak that could kill millions this level of added protection seems to us a must. Moreover, we could substantially reduce the number of BSL3 labs scattered throughout cities and eliminate the need for all planned urban-area BSL4 labs.
The following discussion summarizes some of the new, safe technologies and how they may be applied to development of vaccines, antivirals and antibiotics. The goal is to suggest technologies with which safe research and countermeasure development can be carried out. These new technologies would allow the NEIDL facility to become an important contributor to solving pressing infectious disease problems and conduct biodefense countermeasure development (if it must) in a safe and cost-effective way.
New vaccine technologies
In Table 4, several new vaccine technologies are listed along with comments on their status. The technologies are described in laypersons’ terms with examples and quotations from the scientific literature in Appendix III. The main point from the Table and Appendix, which cannot be emphasized enough, is that none of these technologies require live pathogens, so vaccines using any of them may be developed at low BSL1 or BSL2 levels.
Table 4. Some new vaccine technologies and developments with comments to indicate their status and promise. References and details in Appendix III.
The complete immunity conferred to mice and non-human primates and the strong immune response and safety in humans in the studies in Table 4 (detailed in Appendix III) shows high promise for these new technologies for vaccines against the Category A biological weapons agents. Except for projects where BU researchers are already involved, this calls into question the need to develop additional vaccines for these pathogens. This is especially true of the NEIDL pathogens that require BSL4 containment since those viruses are not a public health threat. Instead, vaccine development for pathogens that are public health concerns in the US or are growing threats would make much more sense as a focus. In those cases, multiple efforts can be justified.
Efficacy demonstrations for vaccines to prevalent pathogens would eventually require clinical trials in humans. In this regard, BU already has plans to carry vaccines through phase I safety clinical trials, so it will have in place the Good Laboratory Practice (GLP) and small-scale manufacturing necessary for FDA approval of phase I trials. NEIDL might consider extending its clinical trial expertise to managing phase II and III clinical trials. The pilot-scale manufacturing for phase II and III clinical trials could be outsourced or carried out in the planned Biomolecule Production Core. This would provide a much needed service to countermeasure developers that include research institutions and biotechnology companies focused on infectious disease.
New thinking at the cutting-edge of vaccine development
Some of the vaccines and technologies in Table 4 incorporate cutting-edge ideas. At a 2007 Keystone Symposium where many of the world’s vaccine experts met, the organizers laid out the challenges.
“Even with the large increase of our understanding of host immune responses, the sequencing of pathogen genomes, and other technological advances, important hurdles remain for developing and deploying vaccines for a variety of diseases. The goals of this meeting will be to bring together scientists, physicians and students from the developed and developing world to discuss the advances in (1) understanding the generation of effective systemic and mucosal immunity at a cellular and organ system level, (2) new technologies for prophylactic and therapeutic immunization, including those useful for resource-poor settings ... ”
Research and cutting-edge ideas and technologies discussed at the meeting for present and future vaccine development include:
understanding mucosal immunity
development of mucosal vaccines (e.g., oral and nasal-spray vaccines)
plant-produced oral vaccines
Manipulating the immune system to improve vaccine performance
transforming innate immunity into adaptive immunity
toll-like receptors and their agonists
Needle-free vaccine delivery
inhaled and nasal aerosols utilizing nanoparticles and stable dry powders
targeting vaccines to the immune system
delivery via lipids
dermal patch delivery
bacterial spores for heat-stable vaccine delivery
Neonatal and infant immunity and vaccines
Development of mouse models for vaccine testing
Some of the ideas and technologies in the bulleted list are still at the research stage and may not find use in actual vaccines for years. Nonetheless, they represent the cutting-edge of vaccine development that should be built into BU NEIDL thinking and activities.
Of particular interest is mucosal immunity and vaccines targeted to mucosal membranes.
Unless we have a wound or some other way directly into the blood stream, pathogens enter the body through the mucous membranes.
The key advantage of vaccines directed to mucosal membranes is that they may be delivered nasally or orally. In response to a pandemic or bioweapons attack oral and nasal vaccines can be self-administered in contrast to syringes, needles, doctors or nurses needed to administer a systemic vaccine.
The problem with biodefense vaccines
Vaccines appear to be a major focus of BU’s NEIDL. But vaccines are not the best approach for defense against a biological weapons attack. They have some unavoidable drawbacks. The Scientists Working Group on Biological and Chemical Weapons of the Center for Arms Control and Non Proliferation’s calls into question the usefulness of biodefense vaccines.
“[A]gencies and programs have been set up at great expense, with the aim of having available stocks of vaccines against potential bioweapons agents. Many questions remain about these programs with respect to vaccine efficacy, safety, shelf life and the ability to perform mass immunizations at short notice. Until these issues are resolved the effectiveness of vaccines as countermeasures remains in doubt.
Countermeasures effective after exposure to anthrax and the smallpox virus, the bioterrorist threat agents of greatest concern, have been developed and stockpiled - antibiotics for anthrax and a vaccine for smallpox. Efforts to accumulate stockpiles of more novel therapeutics, or ones targeted to even less likely bioterrorist threats, are not cost-effective unless they would also serve clear public health goals.”
Of particular note is that an author of this paper is Jack Melling, who was the Chief Executive and Principal Scientific Officer at Porton Down, the UK biological weapons defense facility and UK equivalent to USAMRIID in the US. He also directed the Salk Institute Biologicals Development Center in Pennsylvania and the Karl Landsteiner Institute for Vaccine Development in Vienna, Austria. Melling is among the world’s experts on vaccines against biological weapons agents.
Vaccines have other drawbacks as well. Traditional vaccines protect against one specific, targeted pathogen. If that pathogen is, for example, one of those rare pathogens listed in Table 1, the vaccine will have no public health value in the United States.
The National Institute of Allergy and Infectious Diseases (NIAID) recent update of its biodefense strategy acknowledges this drawback.
“Although the focus of this updated Strategic Plan continues to be on basic research and its application to product development, there is a shift from the current “one bug-one drug” approach toward a more flexible, broad spectrum approach. This approach involves developing medical countermeasures that are effective against a variety of pathogens and toxins, developing technologies that can be widely applied to improve classes of products, and establishing platforms that can reduce the time and cost of creating new products.”
Said another way, vaccines against bioweapons agents and rare diseases are a one-way street. For the most part they have no value for natural diseases prevalent in the US In contrast, broad-spectrum antivirals and antibiotics developed to target prevalent natural diseases will have immediate application to biodefense as well. The broad-spectrum approach is indeed a two-way street, that is a way to meet public health and biodefense needs simultaneously. This would also ensure taxpayers get greater public health value for their tax dollars.
Another NIAID suggestion to “[e]stablish manufacturing platforms ... for rapid and cost-effective production of therapeutics and vaccines for human use. Expand clinical trial capabilities for evaluation of new drugs” should fit well with BU’s NEIDL planned clinical trials expertise.
Focusing on rapid vaccine development and manufacturing methodologies, targeting for example seasonal influenza and other prevalent diseases, would help make BU’s NEIDL particularly relevant to urban community needs. Furthermore, with a focus on diseases already spread throughout the population, escape of the pathogen from the lab would have little consequence.
A better focus: broad-spectrum, small-molecule antivirals and antibiotics
Why small-molecule drugs are far better
Small-molecule antivirals and antibiotics have a number of advantages over biologic drugs and vaccines. A summary comparison is presented in Table 5.
Table 5. Advantages of small-molecule antimicrobials
Insight into cost issues may be gleaned from looking at what the US government pays for various countermeasures for the Strategic National Stockpile (SNS). Cost data for countermeasures procured under BioShield 2004 funding are summarized in Table 6.
Table 6. Number of doses purchased, total cost and cost per dose for countermeasures purchased for the Strategic National Stockpile under Bioshield 2004 funding
References for the numbers are:
On a per dose basis, the most expensive countermeasures are those for the biologic drugs: the humanized monoclonal antibody for anthrax, the passive immunization with immunoglobulins for anthrax, and the polyclonal antibodies for botulinum toxin poisoning. Passive immunization is the most expensive, likely because collecting and processing immunoglobulins from people who have had anthrax vaccinations is expensive. High cost also limits the number of doses that can be purchased for the SNS. Biologic drugs are delivered by injection, which is another drawback in a biodefense and pandemic setting.
Both the anthrax and smallpox vaccines are inexpensive, as the production methods are no more complicated than those for many traditional vaccines. The anthrax vaccine is prepared from a culture filtrate made from a non-virulent strain of Bacillus anthracis and contains no dead or live bacteria. The smallpox vaccine is prepared from a Vaccinia virus strain that cannot replicate in human cells, solving the main safety problem of older smallpox vaccines.
Unfortunately, some vaccines based on new strategies may be expensive if they contain recombinant proteins made by fermentation. For example, the human papillomavirus (HPV) vaccine GARDASIL is priced at $120 per single dose, and three doses are required. The vaccine is prepared from recombinant major capsid (L1) protein of four HPV types using yeast fermentations. Some recombinant vaccines may be considerably more expensive than GARDASIL if they require fermentations of animal cells.
Humanized monoclonal antibody drugs, such as ABthrax, are made by fermentations of animal cells. They can cost several thousand dollars per gram to make. Smaller recombinant proteins can cost hundreds of dollars per gram. Recombinant biologic drugs often sell for thousands of dollars per dose.
In contrast, small-molecule drugs can be produced for $1 to $10 per gram, and usually sell for $1 to $10 a dose, which can be verified simply by visiting any on-line pharmacy. Small-molecule drugs often can be taken orally. Low price and oral delivery are the major advantages that small-molecule drugs offer, which is why they have been and will continue to be the mainstay of the pharmaceutical industry.
The need for new antibiotics and antivirals
Because of increasing microbial resistance to antibiotics, there is an urgent need for new broad-spectrum antibiotics. As reported in the prestigious British medical journal The Lancet
“WHO [World Health Organization] has identified antibiotic resistance as one of the greatest threats to human health ... Yet prospects for replacing current antimicrobial drugs are poor. Only a single new antibacterial - doripenem - has been approved in the USA since 2006 ... [J]ust 15 antibacterial drugs that offer a potential benefit over existing drugs are in development, and only five have reached phase 3 clinical trials. Pharmaceutical companies may not perceive development of antimicrobial drugs to be attractive - owing perhaps to a clinical need restricted to short courses of therapy, and the likelihood that the drugs' useful lives will be truncated by resistance.”
Since there are only a few somewhat effective antivirals in our armamentarium, there is a great need for new broad-spectrum antivirals as well. Only four antiflu drugs are available today: two older drugs amantadine and rimantadine, and the newer zanamivir (Relenza) and oseltamivir (Tamiflu). The state of affairs was described in Chemistry and Engineering News, the magazine of the American Chemical Society.
“Flu virus subtypes are designated by their surface proteins: one of 16 possible hemagglutinins (H1–H16) and one of nine neuraminidases (N1–N9). Despite the large number of possible permutations, human flu is generally caused by H1, H2, and H3 subtypes in combination with N1 or N2.
In principle, four antiviral flu drugs are available. But like many seasonal flu viruses and the H5N1 avian flu strain, novel H1N1 is resistant to amantadine and rimantadine ... Relenza (zanamivir) and Roche’s Tamiflu (oseltamivir), both neuraminidase inhibitors, are still effective.”
But Relenza and Tamiflu are not wonder drugs; and like antibiotics, resistance may develop.
“At best, the available drugs reduce the duration of the illness by a day or so ... Viral resistance could also shorten the drug’s useful life. In the 2007–08 flu season, a Tamiflu-resistant seasonal H1N1 virus unexpectedly arose naturally in Europe. So far, however, only about two dozen isolated cases of Tamiflu resistance in the novel H1N1 virus have appeared ... [The manufacturer Roche emphasizes] the drug’s apparent ability to prevent infection about 90% of the time and to decrease the severity of illness by 40% and hospitalizations by 61%.”
This discussion will focus on new antivirals, not antibiotics, since the BU NEIDL seems to be focusing and building staff in viruses and immunology, although it might consider bringing aboard expertise in bacterial pathogens and antibiotics.
Table 7 provides a summary of promising new antivirals along with comments and status. Details on these new antivirals are found in Appendix V.
Table 7. Some new antivirals in development with comments to indicate their status and promise.
For years, the knock against antivirals has been that they employ our own cell’s “machinery” to reproduce, so most strategies for new antivirals would yield drugs that are not particularly effective or have severe side effects if they didn’t outright kill us. This concern over antivirals seems to be borne out by the fact that there are only four antivirals on the market today (excluding HIV drugs), which aren’t particularly effective. But as virologists learn the molecular details of how virus mechanisms differ from those of the human host, new strategies for antivirals are becoming apparent. New strategies, as evidenced by the drugs described in Table 7 (and in more detail in Appendix V), may be the harbingers of a host of powerful new antivirals.
Now would be the time for the BU NEIDL to consider entering the fray by developing broad-spectrum antivirals for natural infectious disease that could have biodefense applications as well.
A small-molecule drug focus for NEIDL
Small-molecule, broad-spectrum, orally available, and inexpensive new antivirals and antibiotics are the most pressing need for both natural disease and biodefense. In order to refocus on new approaches to small-molecule drugs, NEIDL would need to bring on expertise that they may not now have, in particular medicinal chemistry and rapid screening of drug candidate molecules. A significant medicinal chemistry and screening capability could also serve the Boston area infectious disease research community as well, as both are in short supply. BU should also consider making its Good Laboratory Practice, pilot manufacturing and clinical trial expertise available to academic labs and small biotechnology companies developing new infectious-disease drugs.
Importantly, screening for small-molecule drugs is normally done using in vitro and in vivo reporter assays which do not require access to the intact pathogen. As described earlier, a majority of the work can take place without the pathogen, until the final, live-challenge experiments. These proof-of-efficacy experiments can be carried out in BSL3 and BSL4 laboratories that are equipped to work with those pathogens. Also, broad spectrum antimicrobials can be discovered using less pathogenic microbes; and the most promising drug candidates can then be tested on more pathogenic targets in existing facilities, or eventually in a service facility as proposed here.
We have grave concerns over NEIDL possessing or experimenting with virulent forms of pandemic flu viruses such as the 1918 flu virus. Even though the risk of escape may be small, the consequences could be enormous. Uncomfortable over the resurrection of the 1918 pandemic flu virus by US scientists, Dr. Donald Henderson, who was a leader in the WHO smallpox eradication campaign, said, "The potential implications of an infected lab worker – and [of] spread beyond the lab – are terrifying."
Work with highly contagious, deadly pathogens should be carried out only in facilities far away from population concentrations, as described earlier. To perform the research set forth in this "Alternative Vision," it is not necessary to work with any of the dangerous, live BSL4 pathogens that BU lists for use in its proposed NEIDL. We therefore hope that this Alternative Vision will be adopted.
Appendix I. Letter written by Boston University officials to the National Institute of Allergy and Infectious Disease
Appendix II. Trends in incidence, fatalities and geographic distribution for the BU NEIDL pathogens listed in Table 1.
For Ebola and Marburg viruses, two of the NEIDL pathogens that BU claims as “some of the organisms that will be studied,” trend data for fatalities over time and for geographic distribution are presented below:
For the other pathogens that the BU NEIDL claims it will study, there are either incidence data over time and geographic distribution or written statements indicating that the diseases caused by the pathogens are not increasing over time or range is increasing. These data are presented below.
The following quote provides incidence and fatalities in West Africa, where Lassa fever is endemic:
“The number of Lassa virus infections per year in West Africa is estimated at 100,000 to 300,000, with approximately 5,000 deaths. Unfortunately, such estimates are crude, because surveillance for cases of the disease is not uniformly performed. In some areas of Sierra Leone and Liberia, it is known that 10%-16% of people admitted to hospitals have Lassa fever, which indicates the serious impact of the disease on the population of this region.” http://www.cdc.gov/ncidod/dvrd/spb/mnpages/dispages/lassaf.htm
Kyasanur Forest Disease virus
Among US born persons, incidence of tuberculosis in the US has been decreasing in recent years. For foreign born persons, incidence has remained constant.
“In total, 12,904 TB cases (a rate of 4.2 cases per 100,000 persons) were reported in the United States in 2008. Both the number of TB cases reported and the case rate decreased; this represents a 2.9% and 3.8% decline, respectively, compared to 2007. The TB rate in 2008 was the lowest recorded since national reporting began in 1953 ... There were 644 deaths from TB in 2006, the most recent year for which these data are available. Compared to 1996 data, when 1,202 deaths from TB occurred, this represents a 46% decrease in TB deaths in the last decade.” http://www.cdc.gov/tb/publications/factsheets/statistics/TBTrends.htm
Estimated TB incidence, prevalence and mortality, 2008
Incidence 1 Prevalence 2 Mortality
WHO region no. in thousands % of global total rate per 100 000 pop 3 no. in thousands rate per 100 000 pop no. in thousands rate per 100 000 pop
Africa 2 828 30% 351 3 809 473 385 48
The Americas 282 3% 31 221 24 29 3
Eastern Mediterranean 675 7% 115 929 159 115 20
Europe 425 5% 48 322 36 55 6
South-East Asia 3 213 34% 183 3 805 216 477 27
Western Pacific 1 946 21% 109 2 007 112 261 15
Global total 9 369 100% 139 11 093 164 1 322 20
1Incidence is the number of new cases arising during a defined period.
2Prevalence is the number of cases (new and previously occuring) that exists at a given point in time.
3Pop indicates population.
Globally, more than 1.3 million persons died of tuberculosis in 2008.
Plague causes very few deaths in the United States and is not a major infectious disease concern in the rest of the world.
“About 14% (1 in 7) of all plague cases in the United States are fatal ... Human plague in the United States has occurred as mostly scattered cases in rural areas (an average of 10 to 20 persons each year). Globally, the World Health Organization reports 1,000 to 3,000 cases of plague every year.” http://www.cdc.gov/ncidod/dvbid/plague/resources/plagueFactSheet.pdf
Tularemia or rabbit fever, the disease caused by Francisella tularensis, is rarely fatal. Quoted below are incidence statistics.
“During 1990-2000, a total of 1,368 cases of tularemia were reported to CDC from 44 states, averaging 124 cases (range: 86-193) per year ... Four states accounted for 56% of all reported tularemia cases: Arkansas (315 cases [23%]), Missouri (265 cases [19%]), South Dakota (96 cases [7%]), and Oklahoma (90 cases [7%]).” http://www.cdc.gov/mmwr/preview/mmwrhtml/mm5109a1.htm
Appendix III. Descriptions of new vaccine developments and technologies
Lay-level introduction to vaccines
Vaccines work by stimulating our immune system to recognize and destroy pathogens we may be exposed to in the future. Vaccines often consist of killed or attenuated pathogens that are unable to cause illness. Some modern vaccines employ surface proteins from the pathogen, which are prepared using standard genetic engineering methods, a strategy that does not employ the pathogen at all, so are usually much safer than traditional vaccines.
On first exposure to a killed or attenuated pathogen vaccine, the immune system amplifies specific cells capable of destroying the pathogen and disease from your body. This first-exposure response takes weeks to develop. Once the initial immune response has occurred, the immune system “remembers” the pathogen. The next time you encounter the pathogen, the immune system responds very quickly (faster than the pathogen can proliferate) and protects you from contracting the disease.
Traditional killed or attenuated pathogen vaccines are prepared in several ways, such as heating the pathogen or treating it with chemicals like formaldehyde to render it harmless. There are a number of concerns and dangers to this approach for developing vaccines:
(1) Heat and chemical killed pathogens often do not resemble the virulent pathogen closely enough for your immune system to sufficiently recognize the native pathogen. The resulting vaccine may not provide full protection.
(2) If errors are made in the killing or attenuation process, the vaccine may actually cause the disease it was designed to prevent with sometimes tragic outcomes.
Jonas Salk had created a vaccine using live polio virus that had been inactivated by formaldehyde. In the vaccine made by Cutter Laboratories, one of five manufacturers, virus remained activated. The results, mostly forgotten after more than half a century, were tragic. Of 120,000 children accidentally given activated poliovirus, 40,000 developed mild polio, but 200 were permanently paralyzed and 10 were killed.
(3) There are a small number of serious adverse reactions to many vaccines, for example with the traditional smallpox and Bacillus anthracis vaccines, although there is controversy regarding the extent of adverse reactions for the anthrax vaccine. These adverse reactions show up in mass vaccination programs.
(4) Attenuated virus vaccines could pose significant risk to immune-suppressed populations such as victims of AIDS
New vaccine technologies employ pathogen-mimics or surface proteins that cannot cause infection or disease, so they pose no danger to patients, laboratory workers, or the communities surrounding the laboratory. Most research and development of vaccines using these new technologies may be carried out in BSL1 and BSL2 laboratories since special precautions are not needed. We highlight some of new technologies simply to show they have high promise and are completely safe to work with.
Examples of new, safer vaccine technologies
Virus-like particle vaccines
To the immune system, virus-like particles (VLPs) resemble the virus pathogen closely enough to make effective vaccines. In one method of preparing virus-like particles, surface protein genes from the pathogenic virus are genetically engineered into a virus that does not infect humans, such as a baculovirus that infects only insect cells. Once produced these surface proteins assemble into a structure that closely resembles the surface of the actual virus.
New vaccines on the market use this technology with great success to target hepatitis B and human papilloma virus (Sci-B-Vac and GARDASIL, respectively). Also, Rift Valley fever, and Chikungunya virus have been successfully targeted with VLPs in preclinical studies. Sci B Vac is produced in mammalian CHO cells, GARDASIL in yeast.
For Ebola and Marburg filoviruses, virus-like particles using the VP40 Ebola and Marburg matrix proteins have been produced using the baculovirus system and show high promise as vaccines.
According to one study
“filovirus-like particles produced by baculovirus expression systems, which are amenable to large-scale production, are highly immunogenic and are suitable as safe and effective vaccines for the prevention of filoviral infection.”
This work was carried out at US Army Medical Research Institute of Infectious Diseases, where several NEIDL scientists have close ties. Another USAMRIID study tested VLPs of Ebola and found that they offered 100% protection to monkeys in live challenge experiments.
Large scale production systems for proteins using insect cells infected with baculovirus have been perfected (see for example, http://www.baculovirus.com). Virus-like particles are a very active area of research; for example, a search of the medical research database, PubMed using the search term “virus-like particles” yields close to 3,500 publications that mention the name.
Non pathogenic viruses modified to carry the genes for a virus-pathogen’s surface proteins have been shown to be effective as vaccines. Here we provide one example: an attenuated recombinant vesicular stomatitis virus (rVSV) that makes a glycoprotein from Marburg virus. Non-attenuated VSV can infect humans causing flu-like symptoms.
When monkeys were vaccinated with rVSV with the Marburg glycoprotein after they had been exposed to the Marburg virus, the researchers observed:
“[R]hesus monkeys that were treated with the rVSV ... as a postexposure treatment survived a high-dose lethal challenge of MARV [Marburg virus] for at least 80 days. None of these five animals developed clinical symptoms consistent with MARV. haemorrhagic fever ... [T]hese data suggest that rVSV-based filoviral vaccines might not only have potential as preventive vaccines, but also could be equally useful for postexposure treatment of filoviral infections.”
The example here is also noteworthy as two of NEIDL’s key scientists, Thomas Geisbert and Joan Geisbert participated in the research. Short of challenge experiments utilizing the virulent Marburg virus, this research, too, can be carried out at biosafety levels below BSL4, presumably BSL2.
It is clear from these examples that successful vaccine development to the most dangerous pathogens can be achieved without increasing the number of individuals with access to the virulent pathogens. Indeed, it appears that vaccines for Ebola and Marburg have already been developed.
“Bacterial ghosts,” a concept similar to virus-like particles, is a promising strategy for developing vaccines for gram-negative bacterial pathogens. (Most bacteria may be divided into two types, gram-negative and gram-positive bacteria.)
Bacterial ghosts are empty cells of gram-negative bacteria; that is, all the proteins, DNA and other functional molecules in the bacteria have been drained out, so only the cell wall remains. Preparation of bacterial ghosts utilizes a protein from a virus called PhiX174, which invades gram-negative bacteria. PhiX174 enters the bacteria by employing a protein, called lysis gene E, which punctures holes in the cell wall.
The clever trick to making bacterial ghosts is to genetically engineer the PhiX 174 lysis gene E into the bacterium which will become the ghost. Quantities of the bacterium can be grown up under conditions that the lysis gene and a gene for a DNA nuclease to destroy the bacterium’s DNA are repressed; that is, the genes are not making lysis protein or DNA nuclease. Like the Trojan horse, when sufficient quantities of bacteria have been grown, the two foreign genes may be expressed or “turned on” to produce the lysis protein and the DNA nuclease, resulting in puncture of the cell wall and degradation of the DNA. All the innards will leak out of the cells leaving only the shell or “ghost” of the bacterium.
Bacterial ghosts are a promising vaccine technology as the following quotes attest:
“Proof of concept and proof of principle studies showed that BG candidate vaccines are highly immunogenic and in many instances induce protective immunity against lethal challenge in animal models ... [T]hey are nonliving and devoid of genetic information. The latter aspect is of great importance for safety ... This is an important difference to other chemical-, heat- and pressure- or radiation-inactivated vaccine candidates, which also very often need artificial adjuvants to be added to improve their immunogenicity. The final BG vaccine preparations are freeze dried and are stable for many years at ambient temperature.”
An example study of the bacterium Edwardsiella tarda demonstrates that bacterial ghosts can make more effective vaccine candidates than traditional killed or attenuated bacterial vaccines. E. tarda is a bacterium that can infect wounds and cause diarrhea in animals. The authors note:
“[E. tarda ghost]-immunized mice were significantly protected against E. tarda challenge (86.7% survival) compared to 73.3 and 33.3% survival in the [formalin]-immunized and [no vaccine control], respectively, suggesting that an [E. tarda ghost] oral vaccine could confer protection against infection in a mouse model of disease.”
This study brings up an intriguing possibility, an oral vaccine targeted to the mucosal immune system, which has biodefense appeal since it can be administered quickly and doesn’t require professional administration. An oral vaccine also has appeal in the event of a natural epidemic caused by a gram-negative bacterium disease, such as plague.
Unlike viruses which are usually specific to one host species, bacteria can infect most animal species. Furthermore, most bacteria can be studied under BSL2 containment, and animal challenge studies can perhaps be carried out under BSL3 biocontainment. So there may not be a need for outsourcing challenge studies.
There is considerable Pub Med literature on ghosts of several gram-negative species, including B. anthracis, but curiously no reported studies for gram-negative F. tularensis or Y. pestis, the two Category-A biological weapons agents that BU claims it will research. Developing bacterial ghost vaccines for these two pathogens should be considered by BU. The preparation of the ghosts could be carried out at the NEIDL provided the bacteria require only BSL2 or at most BSL3 containment. We further suggest that the pathogens employed for the ghosts be attenuated strains to reduce the risk of infection from a laboratory accident. For most bacteria, attenuated strains are already available or easy to prepare.
There are no references in Pub Med to ghosts of gram-positive bacteria. A method for making gram-positive ghosts against B. anthracis should be developed, which could provide for an interesting basic research project for the NEIDL.
Toll-like receptor agonist vaccines
Vaccines that consist of only one or more pathogen surface proteins suffer from one big drawback. They often lack potency.
Toll-like receptor (TLR) agonists are molecules that help stimulate immune system cells to combat pathogens. They act like powerful adjuvants. TLR agonists administered with or coupled to pathogen proteins or nucleic acids can make for potent vaccines. This is an exciting new technology that can be used to develop both viral and bacterial vaccines.
A particularly interesting example involves an agonist to a particular toll-like receptor (TLR-3) that serves as a signal to the immune system for the recognition of double-stranded RNA, the genetic material of the seasonal flu and highly pathogenic bird flu viruses. A TLR-3 agonist coupled with double-stranded RNA can serve as a broad-spectrum vaccine against a number of flu viruses and viruses that mutate frequently to fool the immune system. The seasonal flu virus is noted for its rapid mutation rate, so requires a different vaccine each year. The authors of one article conclude
“[T]hese results suggest these TLR-3 agonists have a promising role to play as safe, effective and broad-spectrum anti-influenza drugs that could complement other antiviral drugs to combat seasonal, zoonotic and pandemic influenza viruses. The clinical safety of these drugs and their efficacy in pre-clinical studies may provide sufficient justification for regulatory agencies to consider their fast track development for use in future outbreaks of pandemic influenza or of other emerging respiratory pathogens.”
Another scientific paper on a TLR agonist vaccine for the bacterium Mycobacterium tuberculosis concludes:
“A fusion protein ... was constructed that consisted of ... a potent Toll-like receptor-2 agonist, fused to ... a well-characterized immunogenic protein from Mycobacterium tuberculosis ... [M]ice were significantly protected from low-dose aerosol challenge with M. tuberculosis.”
Yet another paper may point the way to potent oral or nasal vaccines for gram-negative bacteria by using the external flagella that bacteria use to swim.
“Gram-negative flagellin, a Toll-like receptor 5 (TLR5) agonist, is a potent inducer of innate immune effectors…In view of the extraordinary potency of flagellin as an inducer of ... immunity ... we evaluated the efficacy of recombinant Salmonella flagellin as an adjuvant in an acellular plague vaccine. Mice immunized with the F1 antigen of Yersinia pestis and flagellin exhibited dramatic increases in [immune response] ... Importantly, intranasal immunization with flagellin and the F1 antigen was protective against intranasal challenge with virulent Y. pestis ..., with 93 to 100% survival of immunized mice. Lastly, vaccination of cynomolgus monkeys with flagellin and a fusion of the F1 and V antigens of Y. pestis induced a robust antigen-specific IgG antibody response.”
Naked DNA can be used as a vaccine. When DNA sequences for pathogen proteins are injected, the human’s protein production machinery will make the pathogen protein, against which an immune response develops. Since these short pieces of nucleic acid do not code for the complete pathogen, they can be safely employed at BSL2.
DNA vaccines are already under development for biodefense, with efforts underway “for DNA vaccines against several relevant biodefense pathogens: Bacillus anthracis, Ebola and Marburg viruses, smallpox virus, and Venezuelan equine encephalitis virus.”
DNA vaccines, if they can be made potent, are ideal for quick response to a newly encountered pathogen in a biodefense setting. Safety and the ability to evoke the necessary vaccine immune response have been demonstrated for at least one biodefense vaccine, Ebola, in Phase I clinical trails.
“We report the safety and immunogenicity of an Ebola virus vaccine in its first phase I human study. A three-plasmid DNA vaccine encoding the envelope glycoproteins (GP) from the Zaire and Sudan/Gulu species as well as the nucleoprotein was evaluated ... Healthy adults, ages 18 to 44 years, were randomized to receive three injections of vaccine…This Ebola virus DNA vaccine was safe and immunogenic in humans ... Further assessment of the DNA platform alone and in combination with replication-defective adenoviral vector vaccines, in concert with challenge and immune data from nonhuman primates, will facilitate evaluation and potential licensure of an Ebola virus vaccine under the Animal Rule.”
The authors believe they are well underway to FDA approval under the Animal Rule, which applies when it is not possible to test vaccine efficacy on humans when statistics cannot be amassed to demonstrate the effectiveness in preventing disease.
Appendix IV. A primer on mucosal immunity
For vaccines that need to be administered to a large population quickly, mucosal immunity and vaccines targeted to mucosal membranes are of high interest.
“The [m]ucosal immune system is that portion of the immune system which provides protection to an organism's various mucous membranes from invasion by potentially pathogenic microbes. It provides three main functions: protecting the mucus membrane against infection, preventing the uptake of antigens, microorganisms, and other foreign materials, and moderating the organism's immune response to that material ... Because of its front-line status within the immune system, the mucosal immune system is being investigated for use in vaccines ... ”
Unless we have a wound or some other way into the blood stream, pathogens enter the body through the mucous membranes.
“The mucous membranes are one of the largest organs of the body ... Collectively, they cover a surface area of more than 400m2 (equivalent to one and a half tennis courts) and comprise the linings of the gastrointestinal, urogenital and respiratory tracts.”
The location and extent of our mucous membranes is diagramed in Figure 1.
Figure 1. Diagram depicting the extensive mucous membranes in our body.
The red outlines, which are a little difficult to see, of the orifices and organs depicted in white are the mucous membranes.
Because of the importance of mucous membranes as the front-line of our immune system defense, it is surprising that almost all vaccines on the market today and those that appear to be planned for development in the BU NEIDL are systemic vaccines, not mucosal vaccines. Systemic vaccines are delivered to the blood stream by injection. Mucosal vaccines may be delivered orally or nasally, where they activate the mucosal and systemic immune system cells.
The advantage of nasal or oral delivery in response to a pandemic or bioweapons attack is obvious, as oral and nasal vaccines can be self-administered in contrast to syringes, needles, doctors or nurses needed to administer a systemic vaccine.
Appendix V. Descriptions of new antiviral developments and technologies
There are a number of promising neuraminidase inhibitor drugs under development, but their spectrum of activity is limited to flu viruses, albeit an important class of viruses.
“[T]he near-term flu drug pipeline doesn’t hold many candidates because until recently the lackluster market offered few incentives for developers.
Nevertheless, a few candidates look promising. Biota is developing long-acting neuraminidase inhibitors, the most advanced of which is laninamivir…which recently completed Phase III trials in Japan, Taiwan, Hong Kong, and South Korea ...
BioCryst Pharmaceuticals ... is preparing for Phase III studies for its antiviral peramivir ... [O]ne dose of peramivir was found to be as effective as a week’s supply of Tamiflu.
Other antivirals, while initially targeted to flu viruses, may have wider application.
Several small companies want to be the ones to offer such new approaches. San Diego-based NexBio is developing DAS181, an inhaled viral entry blocker that prevents respiratory viruses from infecting cells. According to the developers ‘It is a fusion protein that contains both a sialidase enzyme and a cell-surface-anchoring domain’ ... DAS181 could be used therapeutically and prophylactically.
DAS181 is comprised of two co-joined proteins, as such it may be expensive to manufacture and may sell for a thousands of dollars, if FDA approved. It is unlikely to be of value in a natural pandemic or for a large-scale biological weapons attack, because of cost.
Favipiravir, a broad spectrum antiviral targeting RNA polymerases
One new antiviral drug in discovery, favipiravir (T-705), is generating excitement. It is about to enter Phase III clinical trials for seasonal flu in Japan. Favipiravir works against flu viruses including H5N1, influenza A, influenza B, influenza C, poliovirus, rhinovirus, yellow fever virus, respiratory syncytial virus, arenavirus, and West Nile Virus.
Favipiravir works by an entirely different mechanism from the four available antiviral drugs: it inhibits RNA polymerase, the enzyme necessary to copy the genetic information in RNA viruses to make new virus copies. It does not inhibit DNA synthesis, so does not work on DNA viruses; and more importantly, it does not interfere with the copying of human DNA, which would make it toxic to us. Indeed, it appears quite safe in humans.
LJ001, a broad-spectrum antiviral targeting entry
“LJ001 [is] effective against numerous enveloped viruses* including Influenza A, filoviruses, poxviruses, arenaviruses, bunyaviruses, paramyxoviruses, flaviviruses, and HIV-1. In sharp contrast, the compound had no effect on the infection of nonenveloped viruses. In vitro and in vivo assays showed no overt toxicity. LJ001 specifically intercalated into viral membranes, irreversibly inactivated virions while leaving functionally intact envelope proteins, and inhibited viral entry at a step after virus binding but before virus–cell fusion. LJ001 pretreatment also prevented virus-induced mortality from Ebola and Rift Valley fever viruses.”
*In addition to their protein coat or capsid, some viruses have a lipid “envelope" derived from the host cell membrane covering the capsid.
Some scientists on this project are from Fort Detrick and Harvard Medical School, so again NEIDL scientists have a connection.
RNA interference (RNAi) is a mechanism in human cells that interferes with the process of making proteins from genes by recognizing and degrading the messenger RNA coded by the genes. The drug class is called small interfering RNAs (siRNA). RNA interference is a normal means for controlling what proteins are to be made in a particular human cell at a particular time. RNA interference has also been postulated to be an ancient anti-virus defense mechanism.
siRNA drugs can be readily synthesized to bind to and destroy messenger RNAs from invading viruses. Since the messenger RNA sequences are known for most important viral pathogens and bioweapons agents, siRNA drugs can be developed against these pathogens on short notice. This rapid response capability is of special interest for rapidly emerging diseases such as pandemic flu viruses. The technology allows for development of drug candidates without requiring live pathogen, so development can be carried out in BSL1 and BSL2 laboratories.
In a recently published paper in The Lancet, an RNAi drug was shown to protect macaques from Ebola infection.
“Two (66%) of three rhesus monkeys given four postexposure treatments of the pooled anti-ZEBOV siRNAs were protected from lethal ZEBOV [Zaire Ebola virus] infection, whereas all macaques given seven postexposure treatments were protected. The treatment regimen in the second study was well tolerated with minor changes in liver enzymes that might have been related to viral infection ... This complete postexposure protection against ZEBOV in non-human primates provides a model for the treatment of ZEBOV-induced haemorrhagic fever. These data show the potential of RNA interference as an effective postexposure treatment strategy for people infected with Ebola virus, and suggest that this strategy might also be useful for treatment of other emerging viral infections.”
Although the study was modest, involving only seven macaques, it demonstrates the promise of RNAi drugs.
The main author’s, Thomas Geisbert, institutional affiliations are listed as National Emerging Infectious Diseases Laboratories Institute, Boston University School of Medicine; Department of Microbiology, Boston University School of Medicine; and Department of Medicine, Boston University School of Medicine.
Just across the river from the NEIDL in Cambridge, Alnylam Pharmaceuticals, a leading RNAi company, is headquartered. Among its many drug discovery and development programs, Alnylam has an early-stage collaboration to develop an RNAi drug against Ebola virus. According to the Company’s website
“The NIAID, a division of the National Institutes of Health (NIH) awarded Alnylam a $23M contract to develop an RNAi anti-viral therapeutic against the Ebola virus.”
It is unclear whether BU’s NEIDL and Alnylam are working together as the funding for the work reported in The Lancet is from the Defense Threat Reduction Agency, not NIH.
NEIDL can also take advantage of its proximity to the lab of Craig Mello, who received the Nobel Prize for the discovery of RNAi. He currently heads a group at University of Massachusetts Medical School in Worcester.
The pathogens were listed and identified as targets for study on the Aerobiology Core (http://www.bu.edu/dbin/neidl/en/research/researchSingle.php?id=9) and the Biomolecule Production Core (http://www.bu.edu/dbin/neidl/en/research/researchSingle.php?id=10) sections of the NEIDL website around January 17, 2010. However, the names and some text, including the quote “some of the organisms that will be studied,” were deleted from the website by January 24, 2010.
For the list of Category A, B, and C bioweapons agents and toxins see “Bioterrorism Agents/Diseases,” Centers for Disease Control and Prevention http://www.bt.cdc.gov/agent/agentlist-category.asp
Table A5 in The Global Burden of Disease: 2004 Update, World Health Organization, 2008. http://www.who.int/healthinfo/global_burden_disease/2004_report_update/en/index.html
See for example, Pardis Sabeti’s laboratory website http://www.sabetilab.org/associations.php. Also, in a personal communication with Lynn Klotz she wrote “Based on new work in Nigeria, the Minister of Health is revising it's estimated number of Lassa cases from a few thousand each year to hundreds of thousands of cases and 50,000 deaths. Similarly work is beginning to show that ebola may be widespread in Gabon.”
“Biological Threats a Matter of Balance” January 26, 2010. Issued paper from Scientists Working Group on Biological and Chemical Weapons of the Center for Arms Control and Non Proliferation (http://armscontrolcenter.org)
Boston University Medical Center’s Associate Director of High Containment, Dr. John Tonkiss and the Boston Public Health Commission have stated they do not have plans to regulate these plasmids.
“Staph Fatalities May Exceed AIDS Deaths,” By Lindsey Tanner, The Associated Press, October 17, 2007
“Prospective antibacterial pipeline running dry,” by Talha Burki. The Lancet Infectious Diseases, Volume 9, Issue 11, November 2009, Page 661
A large number of laboratories are researching and developing countermeasures for the Category A bioweapons agents. This is easily confirmed by searching PubMed (http://www.ncbi.nlm.nih.gov/sites/entrez) using the name of any agent as the search term.
“One Bug, One Drug: Boston University’s March to Irrelevance,” Huffington Post May 2, 2010 http://www.huffingtonpost.com/dr-lynn-c-klotz/one-bug-one-drug-boston-u_b_559855.html
“Challenges of Global Vaccine Development,” Keystone Symposia Meeting. Organizer(s): Margaret Liu, Paul-Henri Lambert and Sir Gustav Nossal, Cape Town, South Africa, October 8 - 13, 2007 http://www.keystonesymposia.org/meetings/viewPastMeetings.cfm?MeetingID=905&CFID=2304413&CFTOKEN=64018981
“Biological Threats a Matter of Balance” op. cit.
“NIAID Strategic Plan for Biodefense Research – 2007 Update,” National Institute of Allergy and Infectious Diseases. September 2007 www.niaid.nih.gov
In this document, biologic drugs refer to large-molecule drugs comprised of proteins including monoclonal antibodies (MAbs), DNA RNA, and other large-molecules found in living organisms.
The Project BioShield Act of 2004 authorized $5.6 billion to purchase countermeasures for the Strategic National Stockpile. It was signed into law on July 21, 2004 (P.L. 108-276).
Bavarian Nordic website http://www.bavarian-nordic.com/biodefence/smallpox/imvamune.aspx
J McArdle, “Alternatives to Ascites Production of Monoclonal Antibodies” Animal Welfare Information Center Newsletter, Winter 1997/1998, Vol. 8, no. p3-4. RK Sundaram, et al., “Expression of a functional single-chain antibody via Corynebacterium pseudodiphtheriticum” Eur J Clin Microbiol Infect Dis. 2008 Jul;27(7):617-22. A Lewcock, “”Down on the biopharm,” 17-May-2007 http://www.in-pharmatechnologist.com/Industry-Drivers/Down-on-the-biopharm
“Prospective antibacterial pipeline running dry,” by Talha Burki. The Lancet Infectious Diseases, Volume 9, Issue 11, November 2009, Page 661.
“Flu Fighters,” by Ann M. Thayer. C&EN, Volume 87, Number 39, September 28, 2009 pp. 15 - 26
For a partial list see: http://en.wikipedia.org/wiki/Biosafety_level#List_of_BSL-3_and_BSL-4_facilities. For a map of major facilities see http://www.fas.org/programs/bio/biosafetylevels.html
“Experts fear escape of 1918 flu from lab,” Debora MacKenzie, New Scientist, October 2004 http://www.newscientist.com/article.ns?id=dn6554
Lynn C. Klotz and Edward Sylvester, “Breeding Bio Insecurity: How US Biodefense is Exporting Fear, Globalizing Risk, and Making Us All Less Secure.” The University of Chicago Press, October 2009, based on “Lawsuits Won't Stop Pandemics,” By PAUL A. OFFIT, Wall Street Journal, December 1, 2005
J Cono, CG Casey and DM Bell, “Smallpox Vaccination and Adverse Reactions: Guidance for Clinicians,” Morbidity and Mortality Weekly Report, 2/10/2003
GL. Nicolson, Meryl Nass and NL Nicolson, “Anthrax Vaccine: Controversy over Safety and Efficacy,” American Gulf War Veterans Association http://www.gulfwarvets.com/anthrax5.htm
“Detailed Safety Review of Anthrax Vaccine Adsorbed,” Compiled by the Military Vaccine (MILVAX) Agency US Army Medical Command, February 2009 http://www.vaccines.mil/documents/854AVASafetyRvw.pdf
de Boer SM, Kortekaas J, Antonis AF, Kant J, van Oploo JL, Rottier PJ, Moormann RJ, Bosch BJ. “Rift Valley fever virus subunit vaccines confer complete protection against a lethal virus challenge,” Vaccine. 2010 Mar 8;28(11):2330-9. Epub 2010 Jan 5.
W Akahata et al. “A VLP vaccine for epidemic Chikungunya virus protects non-human primates against infection.” Nature Medicine, Nat Med. 2010 Mar;16(3):334-8. Epub 2010 Jan 28
Warfield KL, Posten NA, Swenson DL, Olinger GG, Esposito D, Gillette WK, Hopkins RF, Costantino J, Panchal RG, Hartley JL, Aman MJ, Bavari S. “Filovirus-like particles produced in insect cells: immunogenicity and protection in rodents.” J Infect Dis. 2007 Nov 15;196 Suppl 2:S421-9.
Warfield KL, Swenson DL, Olinger GG, Kalina WV, Aman MJ, Bavari S., “Ebola virus-like particle-based vaccine protects nonhuman primates against lethal Ebola virus challenge,” J Infect Dis. 2007 Nov 15;196 Suppl 2:S430-7
Daddario-DiCaprio KM, Geisbert TW, Ströher U, Geisbert JB, Grolla A, Fritz EA, Fernando L, Kagan E, Jahrling PB, Hensley LE, Jones SM, Feldmann H. “Postexposure protection against Marburg haemorrhagic fever with recombinant vesicular stomatitis virus vectors in non-human primates: an efficacy assessment.” Lancet. 2006 Apr 29;367(9520):1399-404.
Lubitz P, Mayr UB, Lubitz W. “Applications of bacterial ghosts in biomedicine.” Adv Exp Med Biol. 2009;655:159-70.
Wang X, Lu C. “Mice orally vaccinated with Edwardsiella tarda ghosts are significantly protected against infection.” Vaccine. 2009 Mar 4;27(10):1571-8. Epub 2009 Jan 21.
Wong JP, Christopher ME, Viswanathan S, Dai X, Salazar AM, Sun LQ, Wang M. “Antiviral role of toll-like receptor-3 agonists against seasonal and avian influenza viruses.” Curr Pharm Des. 2009;15(11):1269-74.
Wang B, Henao-Tamayo M, Harton M, Ordway D, Shanley C, Basaraba RJ, Orme IM. “A Toll-like receptor-2-directed fusion protein vaccine against tuberculosis,” Clin Vaccine Immunol. 2007 Jul;14(7):902-6. Erratum in: Clin Vaccine Immunol. 2008 Sep;15(9):1495
Honko AN, Sriranganathan N, Lees CJ, Mizel SB. “Flagellin is an effective adjuvant for immunization against lethal respiratory challenge with Yersinia pestis,” Infect Immun. 2006 Feb;74(2):1113-20
Dupuy LC, Schmaljohn CS, “DNA vaccines for biodefense,” Expert Rev Vaccines. 2009 Dec;8(12):1739-54
Martin JE, et al., “A DNA vaccine for Ebola virus is safe and immunogenic in a phase I clinical trial,” Clin Vaccine Immunol. 2006 Nov;13(11):1267-77
“Mucosal Immunity and Vaccines,” By Robyn Seipp (August 2003) http://www.scq.ubc.ca/mucosal-immunity-and-vaccines
“Compound Found to Safely Counter Deadly Bird Flu,” University of Wisconsin-Madison News: http://www.news.wisc.edu/releases/15718
“A new front line drug for flu in the offing?”
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