1 January 2022 | New Scientist | 9

2022 could be the year when we

find out whether mRNA vaccine

technology can be used for a lot

more than just making vaccines.

The hope is that it can also get our

bodies to produce drugs that are

otherwise very expensive to make,

opening the door to treating a vast

number of conditions.

mRNAs are essentially

genetically coded recipes that

tell cells in our body how to make

proteins, the large molecules that

form most of the machinery of

life. In the case of mRNA vaccines,

the mRNAs code for viral proteins

that provoke an immune response.

When the coronavirus

pandemic began, mRNA vaccines

were still an experimental

technology. There had been only

a few small trials and no vaccines

had ever been approved. Now,

hundreds of millions of people

have received the Pfizer/BioNTech

or Moderna mRNA vaccines, and

these have been found to be very

safe and effective.

This success has given a big

boost to efforts to develop other

mRNA vaccines for everything

from cancers to herpes. But

mRNAs can code for just about

any protein, so the same basic

technology might also allow us

to develop all kinds of treatments.

For instance, cystic fibrosis is

often caused by the lack of a

protein called CFTR in lung cells.

Moderna and another company

called Vertex are developing a

potential treatment, codenamed

VXc-522, that consists of mRNAs

coding for the CFTR protein.

The idea is to deliver them by

inhalation. VXc-522 is currently

undergoing safety testing and

could enter human trials soon

if that goes well.

Moderna is also working with

drug firm AstraZeneca on another

mRNA therapy, this time to get

cells to make a protein called

vascular endothelial growth factor.

VEGF stimulates the growth of

blood vessels, so this treatment,

codenamed AZD8601, could be

used for everything from wounds

that won’t heal to heart disease.

At a conference last November,

the companies announced that

AZD8601 had proved safe in an

initial trial involving injecting it

directly into damaged heart

muscles during surgery. Larger

trials designed to test efficacy

can now get under way.

The potential of mRNA drugs

is enormous. Many protein-based

drugs such as antibodies made

outside the body have proved

extremely effective – but also

extremely expensive. Antibodies

have been called magic bullets

with a hefty price tag, and the

soaring cost of some cancer

treatments has been controversial.

mRNAs could slash both

development times and costs by

setting our bodies to work on the

difficult and time-consuming job

of manufacturing the required

proteins instead. ❚

Michael Le Page

mRNA technology may

treat stubborn diseases

2

A BioNTech worker

tests the procedures

for making mRNA

“ mRNAs could

slash the time

and cost of drug

development

by setting our

bodies to work”

Medicine

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