From Pandemics to Bioterrorism

On 28 March 2008, BioProcess International hosted a panel discussion at the annual INTERPHEX conference (26–28 March 2008 in Philadelphia, PA), titled “From Pandemics to Bioterrorism: The Role of Bio-Manufacturing in Global Healthcare.” The discussion format grew out of a series of conversations over several months involving the panel members, INTERPHEX organizers, and BPI’s editor in chief (all participants are listed on the previous page).

The group started with the premise that the biotechnology industry has a vital role to play in response to global threats of pandemic illness or bioterrorism — threats that are all too real today. Such unique challenges require unique collaborations among diverse participants: private organizations such as the Gates Foundation, public agencies including the Defense Advanced Research Projects Agency (DARPA), the Centers for Disease Control and Prevention (CDC), the National Institutes of Health (NIH), and private industry.

This special report presents highlights from the two presentations and the following panel discussion. Examples of one agency–industry collaboration illustrate what can be accomplished when experienced scientists and engineers from industry work with the government and other partners to address these issues.

Setting The Stage: The Risk Landscape

The first speaker was Melissa Hersh, vice president of global risk intelligence strategies and resiliency solutions, Marsh. She began by providing “a provocative overview of the risk landscape as it pertains to epidemic-prone infectious diseases of any origin, be they naturally occurring, accidental, or deliberate.” She emphasized that “they are all capable of causing public health events of international concern. Although surveillance and response capabilities are mutually beneficial for mitigating the impact of infectious diseases of any origin, the perceived threat of an attack of biological origin needs to be viewed in context with the existing threat of naturally occurring epidemic-prone infectious diseases world wide.”

She explained that the panel would “explore both the positive and negative impacts that political will and economic investments have on infectious-disease management. These include neglected and preventable infectious diseases and infrequently occurring diseases with catastrophic economic and social consequences (such as pandemic influenza) and the potential for human-made and human-spread diseases.” The session was designed to focus on development of platform-based, response-site solutions using novel technologies with novel partnership models — rather than on surveillance preparedness. She continued: “This discussion will cover a set of unique military solutions for rapidly responding to debilitating infectious diseases in a global theater of operations. It describes a cutting edge public-private partnership, which raises a morass of ethical, legal, and regulatory issues. Military attrition caused by infectious disease-related morbidity and mortality has required a long-standing commitment within the defense sector to address public health and infectious disease epidemiology. What we’re going to discuss here is a military solution to a problem that affects our global population, not just soldiers around the world.”

She set the stage by stating that “the potential for a civilian spin-off calls into question a potentially disquieting array of difficult-to-answer questions,” and offered the following as food for thought:

DARPA: The next speaker, Parrish Galliher, founder, president and CTO of Xcellerex, Inc, introduced the Accelerated Manufacturing of Pharmaceuticals (AMP) program, initiated by DARPA. The program began at the end of the second quarter of 2007.

“At this point,” he explained, “we are nearing completion of phase one of the program, which has three overall phases. The problem that we are addressing is novel biological threats and how to respond. Right now, industry has the ability to prepare for known biological threats by stockpiling vaccines for things like smallpox and anthrax. However, these stockpiles have a limited shelf life and therefore require frequent restocking. The system, because of its central supply capability, is vulnerable to threats, and the cold-chain limitations hamper distribution in many under developed areas. In the current system for the preparation of responses to novel biological threats, the manufacturing technologies are too slow to respond and the facilities are inflexible, with fixed pipe systems, for example, that make them too slow to be adapted to new technologies.”

He detailed DARPA’s AMP mission: first, to condense the overall drug development timeline; and second, to develop flexible and mobile production platforms to address the preparedness for novel biothreats no matter where they occur. He described the program’s ambitious goal: “to be able to produce three million does of an antidote — a vaccine or an antibody — to a novel threat for the military in a period of 12 weeks. To accomplish this, DARPA has invested in leading-edge manufacturing technologies. In addition, the initiative provides an opportunity to actually transform the development of biopharmaceuticals.”

Production Yield Goals: Galliher explained his company’s activities within the AMP program. “We are working with both a monoclonal antibody and a subunit vaccine, developing each through three phases in parallel. For each of the phases, the capacity requirement climbs by a factor of 10. The dose assumption for the monoclonal antibody (MAb) is 400 mg and for the subunit vaccine, 40 micrograms. The ultimate goal is to create a technology platform that can produce three million doses of either the subunit vaccine or the MAb in the 12 week timeframe, beginning with cDNA that codes for the antidote subunit vaccine or MAb.”

Product Quality Goals: The approach begins with establishment of three product quality surrogate markers for antibodies: solubility, fragmentation, and folding. Galliher said that “solubility is our metric for ensuring that the drug is in solution. Fragmentation will ensure that the product is going to be stable and not degrade over time or in production. Folding is a surrogate marker of bioactivity with the assumption being that if a protein is folded properly it will be bioactive. In a 12 week timeframe, there would not be time to develop a bioassay specifically tailored to a novel biothreat; ergo, the folding metric. The specifications increase in quality across the three phases. Solubility increases, fragmentation has to be reduced, and folding completion needs to be increased to a high level. Subunit vaccines similarly require quality improvement across the three phases.”

Cost-of-Goods Goals: Galliher told the audience that “i
n phase one, we have set up cost of goods modeling and logistics modeling software systems to lay out the process economics and benefits of various technologies as we evaluate them in the program. The goal of phases one and two is to demonstrate that there is a process economic path and logic to attaining the phase three goal, which is $10 per dose for antibody and $1 per dose for subunit vaccine.

“Each phase of the AMP program lasts about 12 months. At the end of phase two there is an additional three-month live-fire program during which we will be issued DNA by DARPA and will produce a specified amount of product in a specified timeframe. At the end of phase three, we will perform a full-scale demonstration of the production of three million doses in 12 weeks.”

Collaboration: Xcellerex assembled a multidisciplinary team and was awarded a contract by DARPA to work on this technology. The team includes those working with Dowpharma’s Pfenex Expression system and deltaDOT’s capillary electrophoresis Peregrine analytical technology, along with Biopharm Services, the company performing the process and economic modeling. The team is building on the Xcellerex platform, which is already established in high-throughput clone screening and single-use modular manufacturing portable capability. System integration is provided by Pete Latham, cofounder and president of Biopharm Services.

The Rxpedite program, as they named it, started with this multidisciplinary team working in parallel to adapt their current technology platforms to the goals of AMP. Galliher explained that “the middle phase, then, comprises an integration of those technologies from expression to production to fermentation to purification and analytics to create a fully integrated process designed from the bottom up and resulting in a quality-by-design result that meets the goals of the DARPA program.”

He concluded: “What will it take to produce three million doses in 12 weeks? We will be issued cDNA from the organization that created the antidote from the target antigen. We will then begin work to clone and express that target material and use high-throughput screening to select the highest producing clones. During the second stage, we will optimize the process in the high throughput screening and process optimization platform that we are establishing. Third, we will roll that into a scale-up program in a single-use, portable manufacturing platform and begin executing manufacturing batches by week 11, accumulating three million doses of ready-to-formulate bulk vaccine by week 12.”

Expression Technology: Patrick Lucy, global business development leader with Dowpharma, introduced the Pfenex expression technology platform, a Pseudomonas fluorescens–based expression technology that has been developed over the past several years. “The Pseudomonas strain used is a nonpathogenic obligate aerobe gram negative bacterium. The platform is based entirely on the sequencing of the genome of the Pseudomonas fluorescens microbe. Dow used a systems biology approach to establish libraries of host strains and secretion leaders, plasmids, promoters, and is able to screen up to thousands of production strains to get to the optimal strain for production of the protein of interest. We established a high throughput parallel screening method to identify the optimal strain in the least amount of time.

“We’ve developed Pfenex to produce a soluble active protein in vivo, avoiding refolding and getting to the highest amount of yield in the shortest amount of time. “Pfenex introduces multiple expression strategies, multiple strains, robust and rapid fermentation, and then high yield, quality protein output at the other end.”

The AMP program has enabled Dowpharma to build on this platform to establish rapid cloning vectors. Lucy explained: “We have cassettes already made for the gene to be inserted into those vectors. The system can screen hundreds, perhaps thousands, of strains within one week. When we launched the platform in 2004, we were looking at 10–12 strains over a five or six week period. By 2007 we were looking at 100 strains in a three to four week period. In 2008, we’re looking at hundreds to low thousands of strains, in a one-week period to determine the optimal expression strain for the target protein, which has a dramatic impact on the timeline of 12 weeks to make a three million dose goal.”

He explained how the process works. “We have our master host strains stored as glycerol stocks, in 96-well format. In the AMP program, there will be no history for the particular antigen or antibody, so we will screen through the thousands of strains without historical data. Once we select the host strains that we want to evaluate, we array them in plates and then transform our plasmids in a 96-well format, grow them up in an incubator shaker, and do the analysis to look at the expression results. The biggest difference at the 0.5 ML scale between Pfenex and, say, E. coli is that at this scale we’re reaching 40–50 OD units in these wells in contrast with five to 10 for E. coli.”

Pfenex has a low-cost fermentation medium that supports high cell density and therefore high protein yields, which helps contribute to the low cost per unit dose. It can achieve very high cell densities with a completely defined mineral salts medium, so there are no animal-derived components anywhere in the system and there is no antibiotic selection to maintain plasmids. “We use complementation for plasmid maintenance,” Lucy reported. He added that Dowpharma has “achieved cell densities of 100 grams per liter dry cell weight in a fully automated process. It is going from 96 wells to 1 L to 1,000 L, and these process parameters stay consistent throughout. The rapid scale-up meets the needs of the AMP program, and no unique capital is required to process this organism.”

Galliher added that “the Xcellerex platform was originally focused on mammalian cell manufacturing technology, mammalian cell clones, and products produced in mammalian cells. The AMP program is focused on accelerating these platforms to a level suitable to produce three million doses of vaccine or monoclonal antibody in 12 weeks.

“Our PDMax technology is a high-throughput screening and cloning and selection platform. We also use it for high-throughput media optimization for fermentation media development and feed strategies to optimize titer development, for purification optimization and resin screening and it can be used for formulation optimization. We’ve been using a rapid deployment manufacturing technology consisting of disposable manufacturing systems wherever possible, through the entire manufacturing line to bulk product. These systems are modularized in cleanroom environments, and they’re portable to local sites. We use online electronic batch record technology, online quality assurance to give us real time quality updates. The idea here is to adapt PDMax to the Pfenex system, growing bacteria and selecting those that are higher producing. We’re doing the same thing on the second DARPA program, led by Neugenesis, to adapt PDMax to its fungal expression system.”

“The FlexFactory is a portable, mobile contained production system comprising an entire production line from seed vial all the way through to bulk product. It is a very simple facility with the operators outside and the cleanroom containment around only what it needs to be around. The process machinery and the systems inside are single use including bioreactors for fungi and bacteria and downstream systems wherever possible, with online batch record technology and quality assurance check points.”

Panel Discussion

Leah Rosin, associate editor of BioProcess International, moderated the panel discussion. She asked Diana Lanchoney to address the s
ubject of the threat profile by drawing from her unique position at Merck. Lanchoney is the executive director, developing world strategic integration, at the Merck Vaccine Division and Infectious Disease Division.

Lanchoney: Our industry has an incredible role and responsibility in addressing these kinds of challenges whether they’re bioterror challenges or naturally occurring epidemics, in the present, or in the future. There are millions of preventable deaths every year, caused by diseases we already have vaccines for. We have challenges in delivery, in development, and as this program shows, we still have challenges in innovation. That’s probably our primary role as an industry: to keep developing the expertise, attracting the scientists, bridging with academia, and so on to make sure that that stream of innovation continues to generate solutions to these challenges.

The second key piece is that as industry, we have to participate in broad partnerships to enable these innovations to become reality for the populations that need them. That requires a commitment to partnerships with governments, with nongovernmental organizations, with international policy organizations, and in some cases, with donors, so that we can be sure that these innovations make it through R&D, late stage development, procurement, and some sort of market mechanism, and make it out to the populations that need them through a viable delivery system.

Rosin: Government funding for this program has helped companies involved to move forward. How do the realities of corporate financing and profit margins clash with the moral imperative to prepare for such crises?

Galliher: It should be no surprise that we don’t make a lot of money doing this work related to DARPA. We’re doing it because we believe in supporting our military. We also believe that there’s a huge upside for the civilian population in the event of a pandemic or bioterrorism event. Yes, we are benefiting from the work; we’re not making a lot of money, but our technology is being advanced and applied into new spaces. But the real motivation at the board level and the employee level is that we are making a contribution to our capability to withstand any attack.

Lanchoney: A number of factors motivate industry to participate in addressing these challenges. Certainly at Merck we consider addressing global health challenges part of our mission, part of what were really set up to do. It’s a huge inspiration to our employees and also an expectation of our stakeholders, so it’s a very important part of our culture.

But the points that you raise are important. For companies to really contribute, we have to see a set of incentives that enable the whole system to work. Incentives that continue to draw the R&D expertise together, and some of the push funding that we’re seeing through DARPA or through the NIH or the Gates foundation are a key part of that system.

We’re beginning to see incentives that help promising platforms make it through initial development. Some of these are more established for existing infectious disease dilemmas such as the advanced market commitment for vaccines, which was recently started by an international community of donors that set aside over a billion dollars for the procurement of needed vaccines. We’re also seeing incentives created in the US government to help with neglected disease treatment, including the Brownback-Brown Elimination of Neglected Diseases amendment, which helps to provide incentives to companies that want to bring these kinds of products forward. These kinds of incentives, coupled with partnerships and the commitment to innovation are really going to enable industry to participate fully, even when these risks are very high.

Rosin: The Internet was created through government and military projects, so the DARPA program has that historical precedent. Patrick, how has this program helped Dow and the Pfenex expression system advance so that it might be more useful in every day public health needs, and not just specifically for the DARPA program?

Lucy: One of the reasons this program has been successful to date is AMP program manager, Michael Callahan and his team. They make sure each performer is accountable at every phase of the program. There is absolute clarity in the expectations in this program, quarter to quarter. The ability to integrate our technologies with Xcellerex’s platform and to show proof of concept of Pfenex in that platform, obviously is a great commercial opportunity. There were many different motives for doing the program, but the R&D in particular has really pushed our platform to levels of speed and productivity that we did not anticipate.

Rosin: Melissa, what kind of risks would companies be taking to approach these problems without that kind of funding? Also, with different funding mechanisms, there are different intellectual property challenges and different regulatory restrictions for freedom to operate and incorporate incentives. Would you talk about that?

Hersh: If you’re a manufacturing company, are you supposed to maintain your facilities at all times on standby? Is that sustainable? Are your stakeholders going to pay for that? What unique solutions are there? What kind of return is there? Can your facilities be considered eminent domain? How is the government going to step in and subsidize? If you’re producing regular influenza countermeasures for seasonal flu, is there any reason for you to then shut down those processes to start pandemic flu capabilities? We don’t know.

There are tons of questions related to what supplier agreements you have on hand, issues related to rapid production, and then of course rapid recall in the commercial sector. The risks are so plentiful and the proof of concept is just now being discussed. The AMP program may realistically relate only to the military arena. I don’t know yet if the ethical and legal and regulatory issues can be surmounted in the public sphere.

Galliher: I think that Melissa represents the current situation well. When DARPA looked at this, it saw the conversion of manufacturing capability to a rapidly expandable capacity as the critical first step. A company faced with having to redirect existing facilities to produce a novel countermeasure would have an alternative: to rapidly expand or install a new factory able to produce the product, to produce or screen a large variety of organisms and a large variety of countermeasures very rapidly to get around that bottleneck.

Rosin: Diana, do you have anything to say about public–private partnerships and whether this is attractive only for large pharmaceutical and large biotech companies, or whether this is something that small start ups and entrepreneurial companies are getting into? If so, what are the incentives for those companies?

Lanchoney: We see growth in push funding from charitable sectors, defense sectors, and governmental sectors that are beginning to recognize the value of highly exploratory research programs such as this that have the potential to affect multiple applications. We see growth in the funds available to companies engaging in research on neglected diseases or epidemics. There is recognition that the private sector needs to be deeply engaged and needs to have at a minimum its costs recovered to engage in this kind of research. Further downstream, there are some other important kinds of incentives coming.

Risks are not always financial. We can have as explicit a dialog as possible with policy groups and regulators to understand just how a product like this will have to be configured to be accepted when and where it is needed. The policy and regulatory community can address specific needs and specific problems.

Similarly, there are risks around market and procurement and delivery. Push investments need to be coupled with coherent dialog on the regulatory pathway and on the procurement. There are some promising examples
of this such as government-owned, contractor-operated facilities for pandemic flu vaccines.

Pete Latham of Biopharm Services asked how a company might use the flexibility of the platform to have a facility that’s up and running and making things, but still be able to transition rapidly in the event of a crisis.

Lucy: Based on the metrics that we’ve achieved so far during phase one of the AMP program, the platform has shown that it is not only flexible, but also deployable. The speed and flexibility of the Pfenex expression technology combined with the rapid deployability of the Xcellerex platform makes this a great combination.

Galliher: One of the reasons why we like the Pfenex technology is that it’s a very rapidly growing organism. A mammalian cell organism is normally going to take two to three weeks to produce a batch of product. We can do a Pfenex fermentation in two days, or less. The ability to move quickly, do a SWAT campaign to produce three million doses for the army, deliver that and get back to business as usual is afforded by these technologies. The focus of all the DARPA programs, not just ours, is this ability to be extremely agile, to ensure minimum downtime, minimum flip-over time, minimum execution time, and minimum time to deliver the drug and then get back to business. The advent of these technologies is going to create a whole new landscape in which the on-call responsiveness can be accommodated with new age factories that need to operate as businesses and make money.

Rosin: It occurs to me that a FlexFactory is probably pretty expensive. And the cost per dose has to be pretty low. Did the advantage of already having the FlexFactory help you accomplish that need in the DARPA program?

Galliher: The focus is to have an existing FlexFactory capability that can be switched to grow Pfenex in a moment’s notice. That’s the concept behind disposable insertion systems or liner systems that can be inserted quickly, used to execute a particular culture or particular process, and then switched out quickly to do something different. We’re now setting the FlexFactory up for bacteria, but the end goal will be to have a universal platform that can run mammalian cells one day and bacteria the next day. And then yeast, and then insect cells, and then fungi, such that you come to more of a universal plant concept with enormous agility.

Lanchoney: When the cycle time and capital required are greatly reduced, that has an impact on the entire range of opportunity costs including the manpower, the capital, the inventory, the storage, the stockpiling of intermediates, and of course, if we’re really able to eliminate the cold chain, a vast investment in the cold chain world wide. I recently heard from the Global Alliance for Vaccines and Immunization in Geneva that when they estimate the program costs of administering vaccines to developing world populations, the cold chain alone is 40% of the program cost.

Rosin: Melissa, do you have anything to add about how this type of platform could meet the moral and ethical challenges of dealing with diseases in the developing world? Does it give you any more hope, or do you think that we’re still not ready because of all the other challenges?

Hersh: The opportunity certainly exists for industry to step up, and/or for governments to meet industry halfway, but what responsibility lies where is a difficult question. It affords us a technical opportunity and an advancement that allows us to make decisions. It also poses the need for some decisions to be made in real time. If another respiratory disease appears in a developed county it’s one thing, but if it’s foot-and-mouth disease in Argentina or Brazil, or rinderpest in another country, or brucellosis in Mongolia, what do we do? Who defines which epidemic we respond to? It’s not only what the commitment is, but also whether there is a priority check list of what gets addressed.

Rosin: Conversely, what role do companies in the United States have in meeting those needs in foreign countries?

Hersh: US and European companies now have manufacturing facilities in China. They’ll probably want to invest in preparedness and response capabilities, not just for the local populations, but also for their corporations, and there’s a direct relationship. If you’re a backyard chicken farmer and you work on the assembly line at a plant and you develop avian influenza and there’s no local public health infrastructure, on whom does the burden fall? Is it on the corporation, to prevent the spread of a potentially devastating social and economic disease, or does the local government bear that burden? There are extra-territoriality issues, there are legislative issues, sovereignty issues, and they open up an enormous can of worms. As Diana said, there needs to be a very frank and explicit conversation and not necessarily one that happens in private.

Lanchoney: I think the biggest success stories have occurred when there really is commitment to a mutual goal, and engagement from everyone toward a common objective — from companies, government, NGOs, and local communities. In the case of Merck’s Mectizan, a treatment for river blindness prevalent in many of the world’s most impoverished nations, the product was developed; the clinical trials showed us that you need only one dose a year to control the disease. It is an easy-to-administer tablet, requiring relatively simple storage conditions and minimal surveillance after administration. This was a sort of home run in an innovative technology, and yet there was no way to deliver it, even after Merck made a commitment to donate it free of charge as long as the product was needed. The delivery problem was overcome by a number of international, national, and local organizations and Merck coming together to form the Mectizan Donation Program, working with local ministries of health, down to the level of local village leaders, to help develop community-based treatment programs. The infrastructure that was developed around this one product became the basis for other healthcare interventions that have been administered since. Similarly, in the case of bioterrorism, you’re going to have to engage a broad range of public and private entities to get the job done. We need to start thinking with that transformative paradigm in mind.

Rosin: The DARPA program’s three million doses seems like a drop in the bucket when you look at just the population of the United States, let alone global populations. Would it really be possible to scale it up to provide a dose for every person in the United States, or even for every healthcare worker? What do you see as the potential in this regard?

Galliher: We need to be careful about what we conclude at this stage. However, if we continue in the direction that we’ve been going, with the results that we’ve achieved, we do have the ability to address much, much larger populations. You have to be careful, in addition, because results could be product dependent. That’s a high risk element of these programs: You have only a certain amount of time to look at just so many molecules. Part of the program focus is to work with as many different molecules as possible. That’s why there’s a monoclonal antibody — a very complex heterodimer molecule with complex folding that has to present epitopes — as a model of a very difficult to produce product and then at the other extreme, a relatively small protein-based subunit vaccine. If you can get both of those to work, you probably have covered the best case and the worst case scenarios. We want to end up with a platform that can use any type of expression system, that can clone any molecule and express it, but we needed to start at a focused place.

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