POLICY BRIEFING
RNA vaccines: an introduction
October 2018
Laura Blackburn
Vaccination is one of the major success stories of modern medicine,
greatly reducing the incidence of infectious diseases such as measles,
and eradicating others, such as smallpox. Conventional vaccine
approaches have not been as effective against rapidly evolving
pathogens like influenza or emerging disease threats such as the
Ebola or Zika viruses. RNA based vaccines could have an impact in
these areas due to their shorter manufacturing times and greater
effectiveness. Beyond infectious diseases RNA vaccines have potential
as novel therapeutic options for major diseases such as cancer.
Summary
• Unlike a normal vaccine, RNA vaccines work by introducing an mRNA sequence (the molecule which tells
cells what to build) which is coded for a disease specific antigen, once produced within the body, the
antigen is recognised by the immune system, preparing it to fight the real thing
• RNA vaccines are faster and cheaper to produce than traditional vaccines, and a RNA based vaccine is also
safer for the patient, as they are not produced using infectious elements
• Production of RNA vaccines is laboratory based, and the process could be standardised and scaled,
allowing quick responses to large outbreaks and epidemics
• Most current research is into RNA vaccines for infectious diseases and cancer, for which there are several
early-stage clinical trials, there is also some early research into the potential of RNA vaccines for allergies
• There is still a lot of work to be done before mRNA vaccines can become standard treatments, in the
meantime, we need a better understanding of their potential side effects, and more evidence of their
long term efficacy
POLICY BRIEFING
What are RNA vaccines and how do they work?
Conventional vaccines usually contain inactivated disease-causing organisms or proteins made by the
pathogen (antigens), which work by mimicking the infectious agent. They stimulate the body’s immune
response, so it is primed to respond more rapidly and effectively if exposed to the infectious agent in the
future.
RNA vaccines use a different approach that takes advantage of the process that cells use to make proteins:
cells use DNA as the template to make messenger RNA (mRNA) molecules, which are then translated to build
proteins. An RNA vaccine consists of an mRNA strand that codes for a disease-specific antigen. Once the
mRNA strand in the vaccine is inside the body’s cells, the cells use the genetic information to produce the
antigen. This antigen is then displayed on the cell surface, where it is recognised by the immune system.
How are RNA vaccines produced and administered?
A major advantage of RNA vaccines is that RNA can be produced in the laboratory from a DNA template
using readily available materials, less expensively and faster than conventional vaccine production, which
can require the use of chicken eggs or other mammalian cells.
RNA vaccines can be delivered using a number of methods: via needle-syringe injections or needle-free into
the skin; via injection into the blood, muscle, lymph node or directly into organs; or via a nasal spray. The
optimal route for vaccine delivery is not yet known. The exact manufacturing and delivery process of RNA
vaccines can vary depending on the type.
Types of RNA vaccine
1. Non-replicating mRNA
The simplest type of RNA vaccine, an mRNA strand is packaged and delivered to the body,
where it is taken up by the body’s cells to make the antigen.
2. In vivo self-replicating mRNA
The pathogen-mRNA strand is packaged with additional RNA strands that ensure it will be
copied once the vaccine is inside a cell. This means that greater quantities of the antigen are
made from a smaller amount of vaccine, helping to ensure a more robust immune response.
3. In vitro dendritic cell non-replicating mRNA vaccine
Dendritic cells are immune cells that can present antigens on their cell surface to other types of
immune cells to help stimulate an immune response. These cells are extracted from the patient’s blood,
transfected with the RNA vaccine, then given back to the patient to stimulate an immune reaction.
Benefits
Benefits of mRNA vaccines over conventional approaches are1:
Safety: RNA vaccines are not made with pathogen particles or inactivated pathogen, so are non-infectious.
RNA does not integrate itself into the host genome and the RNA strand in the vaccine is degraded once the
protein is made.
Efficacy: early clinical trial results indicate that these vaccines generate a reliable immune response and are
well-tolerated by healthy individuals, with few side effects.
Production: vaccines can be produced more rapidly in the laboratory in a process that can be standardised,
which improves responsiveness to emerging outbreaks.
POLICY BRIEFING
Important challenges
The methods to make mRNA vaccines can be very effective. However, there are technical challenges to
overcome to ensure these vaccines work appropriately:
Unintended effects: the mRNA strand in the vaccine may elicit an unintended immune reaction. To minimise
this the mRNA vaccine sequences are designed to mimic those produced by mammalian cells.
Delivery: delivering the vaccine effectively to cells is challenging since free RNA in the body is quickly
broken down. To help achieve delivery, the RNA strand is incorporated into a larger molecule to help stabilise
it and/or packaged into particles or liposomes.
Storage: many RNA vaccines, like conventional vaccines, need to be frozen or refrigerated. Work is ongoing
to reliably produce vaccines that can be stored outside the cold chain, since these will be much more
suitable for use in countries with limited or no refrigeration facilities.
How could RNA vaccines be used for human health?
The most active areas of research into RNA vaccines are infectious diseases and cancer where there is
research ongoing as well as early-stage clinical trials. Work into the use of RNA vaccines to treat allergy is still
at the early research stage2.
Infectious diseases
Researchers using conventional approaches have
struggled to develop effective vaccines against
a number of pathogens, particularly viruses, that
cause both acute (Influenza, Ebola, Zika) and
chronic (HIV-1, herpes simplex virus) infection.
RNA vaccines are being explored as a way to more
rapidly and cheaply produce vaccines for these
diseases, particularly in response to emerging
outbreaks. Clinical trials have been carried out
or are ongoing on mRNA vaccines for influenza,
cytomegalovirus, HIV-1, rabies and Zika virus.
Cancer vaccines
Cancer vaccines are a form of immunotherapy,
where the vaccine triggers the immune system
into targeting the cancer. Both dendritic cell
vaccines and personalised cancer vaccines,
where the RNA sequence in the vaccine is
designed to code for cancer-specific antigens,
are being explored. Over 50 clinical trials are
listed on clinicaltrials.gov for RNA vaccines in
a number of cancers, including blood cancers,
melanoma, glioblastoma (brain cancer) and
prostate cancer.
Case study: A recent study3 explored the
use of programmable self-replicating RNA
vaccines, delivered in a nanoparticle, for
a range of infectious diseases including
Ebola virus, H1N1 Influenza and Toxoplasma
gondii, which were effective in mice.
These vaccines can be manufactured
in approximately one week and made
against a range of diseases, demonstrating
potential terms of swift response to disease
outbreaks.
Case study: Researchers sequenced the
genomes of tumours from patients with
melanoma. They made RNAs coding for
mutant proteins, specific to the patients’
cancers, that could generate an immune
response and made these into patientspecific
vaccines. Eight out of thirteen
people vaccinated stayed tumour free up
to two years later4.
POLICY BRIEFING
@PHGFoundation
www.phgfoundation.org
PHG Foundation is a health policy think tank with a special focus on how
genomics and other emerging health technologies can provide more
effective, personalised healthcare
RNA vaccines – who’s involved?
There are a number of companies and initiatives with an interest in RNA vaccines including the Merit
Consortium, which is a European initiative to develop cancer vaccines, while UniVax is a research
collaboration to develop a universal influenza vaccine. Companies such as Moderna Therapeutics,
CureVac and BioNTech, are involved in phase I trials of RNA vaccines in cancer and infectious
disease. These companies are also exploring the broader use of RNA therapeutics for diseases where
important proteins are missing or defective and mRNA treatments could be used to express a
functional copy of the protein.
Harnessing RNA vaccines for health – what are the challenges and key
considerations?
• Research and clinical trials: further research is needed to address technical hurdles such as
vaccine stability and delivery. It is not yet certain which production method(s) are currently
the best. Clinical trial data is limited – more long-term studies are needed to determine the
effectiveness of RNA vaccines.
• Production: vaccine production is currently small scale and it is not clear if current methods
are capable of epidemic-level vaccine production.
• Resources: the personalised approach for cancer vaccines is time and resource intensive and
work is needed to determine if this approach is cost-effective.
• Safety: better understanding of vaccine adverse effects is needed – these can include
inflammation or autoimmune reactions.
References
1. Pardi N, Hogan MJ, Porter FW, et al. mRNA vaccines – a new era in vaccinology. Nat Rev Drug Discov.
2018; 17(4): 261-279.
2. Weiss R, Scheiblhofer S, Thalhamer, J. Generation and Evaluation of Prophylactic mRNA Vaccines Against Allergy. Methods
Mol Biol. 2017; 1499: 123-139.
3. Chahal JS, Kahn OF, Cooper CL, et al. Dendrimer-RNA nanoparticles generate protective immunity against lethal Ebola,
H1N1 influenza, and Toxoplasma gondii challenges with a single dose. Proc Natl Acad Sci USA. 2016; 113(29): E4133-42.
4. Sahin U, Derhovanessian E, Miller M, et al. Personalized RNA mutanome vaccines mobilize poly-specific therapeutic
immunity against cancer. Nature. 2017; 547(7662): 222-226.
Are you busy and do not have time to handle your assignment? Are you scared that your paper will not make the grade? Do you have responsibilities that may hinder you from turning in your assignment on time? Are you tired and can barely handle your assignment? Are your grades inconsistent?
Whichever your reason is, it is valid! You can get professional academic help from our service at affordable rates. We have a team of professional academic writers who can handle all your assignments.
Students barely have time to read. We got you! Have your literature essay or book review written without having the hassle of reading the book. You can get your literature paper custom-written for you by our literature specialists.
Do you struggle with finance? No need to torture yourself if finance is not your cup of tea. You can order your finance paper from our academic writing service and get 100% original work from competent finance experts.
Computer science is a tough subject. Fortunately, our computer science experts are up to the match. No need to stress and have sleepless nights. Our academic writers will tackle all your computer science assignments and deliver them on time. Let us handle all your python, java, ruby, JavaScript, php , C+ assignments!
While psychology may be an interesting subject, you may lack sufficient time to handle your assignments. Don’t despair; by using our academic writing service, you can be assured of perfect grades. Moreover, your grades will be consistent.
Engineering is quite a demanding subject. Students face a lot of pressure and barely have enough time to do what they love to do. Our academic writing service got you covered! Our engineering specialists follow the paper instructions and ensure timely delivery of the paper.
In the nursing course, you may have difficulties with literature reviews, annotated bibliographies, critical essays, and other assignments. Our nursing assignment writers will offer you professional nursing paper help at low prices.
Truth be told, sociology papers can be quite exhausting. Our academic writing service relieves you of fatigue, pressure, and stress. You can relax and have peace of mind as our academic writers handle your sociology assignment.
We take pride in having some of the best business writers in the industry. Our business writers have a lot of experience in the field. They are reliable, and you can be assured of a high-grade paper. They are able to handle business papers of any subject, length, deadline, and difficulty!
We boast of having some of the most experienced statistics experts in the industry. Our statistics experts have diverse skills, expertise, and knowledge to handle any kind of assignment. They have access to all kinds of software to get your assignment done.
Writing a law essay may prove to be an insurmountable obstacle, especially when you need to know the peculiarities of the legislative framework. Take advantage of our top-notch law specialists and get superb grades and 100% satisfaction.
We have highlighted some of the most popular subjects we handle above. Those are just a tip of the iceberg. We deal in all academic disciplines since our writers are as diverse. They have been drawn from across all disciplines, and orders are assigned to those writers believed to be the best in the field. In a nutshell, there is no task we cannot handle; all you need to do is place your order with us. As long as your instructions are clear, just trust we shall deliver irrespective of the discipline.
Our essay writers are graduates with bachelor's, masters, Ph.D., and doctorate degrees in various subjects. The minimum requirement to be an essay writer with our essay writing service is to have a college degree. All our academic writers have a minimum of two years of academic writing. We have a stringent recruitment process to ensure that we get only the most competent essay writers in the industry. We also ensure that the writers are handsomely compensated for their value. The majority of our writers are native English speakers. As such, the fluency of language and grammar is impeccable.
There is a very low likelihood that you won’t like the paper.
Not at all. All papers are written from scratch. There is no way your tutor or instructor will realize that you did not write the paper yourself. In fact, we recommend using our assignment help services for consistent results.
We check all papers for plagiarism before we submit them. We use powerful plagiarism checking software such as SafeAssign, LopesWrite, and Turnitin. We also upload the plagiarism report so that you can review it. We understand that plagiarism is academic suicide. We would not take the risk of submitting plagiarized work and jeopardize your academic journey. Furthermore, we do not sell or use prewritten papers, and each paper is written from scratch.
You determine when you get the paper by setting the deadline when placing the order. All papers are delivered within the deadline. We are well aware that we operate in a time-sensitive industry. As such, we have laid out strategies to ensure that the client receives the paper on time and they never miss the deadline. We understand that papers that are submitted late have some points deducted. We do not want you to miss any points due to late submission. We work on beating deadlines by huge margins in order to ensure that you have ample time to review the paper before you submit it.
We have a privacy and confidentiality policy that guides our work. We NEVER share any customer information with third parties. Noone will ever know that you used our assignment help services. It’s only between you and us. We are bound by our policies to protect the customer’s identity and information. All your information, such as your names, phone number, email, order information, and so on, are protected. We have robust security systems that ensure that your data is protected. Hacking our systems is close to impossible, and it has never happened.
You fill all the paper instructions in the order form. Make sure you include all the helpful materials so that our academic writers can deliver the perfect paper. It will also help to eliminate unnecessary revisions.
Proceed to pay for the paper so that it can be assigned to one of our expert academic writers. The paper subject is matched with the writer’s area of specialization.
You communicate with the writer and know about the progress of the paper. The client can ask the writer for drafts of the paper. The client can upload extra material and include additional instructions from the lecturer. Receive a paper.
The paper is sent to your email and uploaded to your personal account. You also get a plagiarism report attached to your paper.
GET A PERFECT SCORE!!! 
Delivering a high-quality product at a reasonable price is not enough anymore.
That’s why we have developed 5 beneficial guarantees that will make your experience with our service enjoyable, easy, and safe.
You have to be 100% sure of the quality of your product to give a money-back guarantee. This describes us perfectly. Make sure that this guarantee is totally transparent.
Read moreEach paper is composed from scratch, according to your instructions. It is then checked by our plagiarism-detection software. There is no gap where plagiarism could squeeze in.
Read moreThanks to our free revisions, there is no way for you to be unsatisfied. We will work on your paper until you are completely happy with the result.
Read moreYour email is safe, as we store it according to international data protection rules. Your bank details are secure, as we use only reliable payment systems.
Read moreBy sending us your money, you buy the service we provide. Check out our terms and conditions if you prefer business talks to be laid out in official language.
Read more