The Economist - USA (2020-08-29)

66 Science & technology The EconomistAugust 29th 2020

2 Brachiosaurus. A prototypeofthisconfigu-

rationisalreadyrunningaroundthecom-

pany’soffices,openingandshuttingdoors.

ThisversionofSpotshouldgoonsale

nextyear.AsforAtlas,BostonDynamics’s

humanoid,thatiscurrentlytooexpensive

tospawna commercialversion.Buttheles-

sonsbeinglearntfromitwillhelpprovide

theengineeringneededforotherrobotsto

come,saysMrPerry.

Someofthesewalkingrobotsofthefu-

turemaynotbedeployedonthisworld.At

Caltech,DrAmesthinksrobotswithlegs

willhaveadvantagesinplanetaryexplora-

tion—negotiatingdifficultterrainanden-

teringcaves,forexample.Meanwhile,back

onEarth,heandsomecolleaguesatother

institutionsareusingthenewknowledge

of robotic locomotion to develop light-

weightprostheticdevicesforthoseunable

towalkeasily,andpoweredexoskeletons

forthosewhocannotwalkatall.Ina world

notmadeforwheels,thisraisesthetanta-

lisingprospectthatwalkingrobotswillone

dayhelpridtheworldofwheelchairs. 7

W

hat do amalaria drug, a Russian vac-

cine and the blood plasma of people

who have recovered from covid-19 have in

common? All have been approved for use

by governments in response to the corona-

virus pandemic, with little or no scientific

substance to back those decisions up.

On March 28th, near the pandemic’s be-

ginning, America’s Food and Drug Admin-

istration (fda) issued emergency-use au-

thorisation for hydroxychloroquine, an

established but not risk-free antimalarial

medicine which was controversially being

proposed by some people, including Do-

nald Trump, the country’s president, as a

possible covid treatment. It did so, the au-

thorisation stated, based on “limited in vi-

troand anecdotal clinical data”. On August

11th Vladimir Putin, Mr Trump’s Russian

counterpart, said his government was the

world’s first to approve a coronavirus vac-

cine, despite a lack of proper tests. And on

August 23rd Mr Trump announced approv-

al of the use of convalescent plasma thera-

py to treat covid-19. He described it as a

“very historic breakthrough” on the basis

of a study the statistics of which the head of

the fda, Stephen Hahn, got publicly and

spectacularly wrong.

That regulators move fast in emergen-

cies is to be applauded. But these three ex-

amples have raised worries that sometimes

they are moving too fast, and possibly for

the wrong reasons. In one instance, in-

deed, things have gone full circle. Hydroxy-

chloroquine’s approval was rescinded on

June 15th, after a series of well-conducted

trials showed that it had no effect on co-

vid-19. The worry is that the other two ap-

proaches may prove similarly futile—di-

verting attention and effort from more

promising avenues or, worse, causing actu-

al harm.

Don’t just say “yes”

The Russian announcement was of the de-

velopment, by the Gamaleya Research In-

stitute of Epidemiology and Microbiology,

in Moscow, of Sputnik V. This involves two

injections, three weeks apart (see chart).

Each shot is of a harmless virus that has

been modified to express one of the pro-

teins made by sars-cov-2, the virus that

causes covid-19. This is a perfectly sensible

approach. Unfortunately, Sputnik V has

not yet been through the trials, normally

involving many thousands of people,

which would be needed to show that it

works and is safe. In fact, it has been given

to a mere 76 people, and no results from

these tests (nor from any of the animal

tests that the institute says it has run) have

yet been published. Mr Putin has, in other

words, simply redrawn the finishing line

for making a vaccine, stepped over it, and

declared victory.

America’s behaviour is not much better.

Again, the approach behind the product

approved is reasonable in principle, but in-

sufficiently tested. Convalescent plasma

therapy transfuses blood plasma from

those who have recovered from an infec-

tion (and which is therefore rich in anti-

bodies against whatever had infected

them) into patients with the illness to be

treated. As Soumya Swaminathan, chief

scientist of the World Health Organisation

(who), observes, this tactic has been used

to treat infectious diseases for over 100

years, and is effective against some, but not

others. Trials of it as a treatment of covid-19

are therefore under way around the planet,

but Dr Swaminathan says the results so far

are “not conclusive”, and the trials them-

selves have been small. As a result, the who

considers it an “experimental therapy”.

Not so, apparently, the fda. Mr Trump

made his announcement with Dr Hahn on

the same platform. Two things have upset

people about this. One is that the basis for

the emergency approval was an observa-

tional study of ways of administering plas-

ma (either less or more than three days

after diagnosis) rather than a randomised

controlled trial in which some patients

were given a placebo instead of the treat-

ment under test. The other is that, even

granted this difference, the advantage seen

in the study in question was too inconclu-

sive to justify the approval given.

Dr Hahn described the benefits of treat-

ing early with convalescent plasma by say-

ing that, “if the data continue to pan out,

[of ] 100 people who are sick with covid-19,

35 would have been saved because of the

administration of plasma”. Jonathan Rei-

ner, a professor of medicine at the George

Washington University Medical Centre,

tweeted that this was “shockingly wrong”,

and that the actual figure was 3.2. Dr Hahn

has since clarified that he confused the rel-

ative reduction in risk of mortality (of 35%

between the two arms of the study) with an

absolute risk reduction. That is a pretty

fundamental mistake.

Meanwhile, in Hong Kong—a part of the

world which looked as though it had sars-

cov-2 under control—news has emerged of

someone who, having had covid-19 once

and recovered, has now been infected by a

slightly different strain of the virus. Extra-

polating from a single case is risky, but this

one calls into question how long someone

who recovers from infection retains im-

munity from re-infection. The answer is

crucial to understanding how herd immu-

nity to the virus develops in populations,

and may also have implications for vaccine

development. Doctors will now be looking

hard for similar examples, so that such un-

derstanding can be improved.^7

Politics and medicine approvals should

not be mixed

Covid-19

Trials and

tribulations

From Russiawithantibodies

MechanismoftheSputnikV vaccineforcovid-19

Source:SputnikVaccine.com

The Sputnik Vvaccineis aimedat

the spike-protein molecules that

line the outside surface of the

coronavirus particle and allow

it to enter and infect cells

Tomakethevaccine,researchers

embed RNA that encodes spike

protein in two handicapped viruses

called vectors. The vectors create

spike protein, but do not cause illness

Thetwovectors are administered

21 days apart. Each causes the body

to produce antibodies against spike

protein, priming the immune

system to fight off SARS-CoV-2

SARS-CoV-2

Virus responsible

forcovid-19

AD26

AD5

Antibodies

Vectors

AD26 AD5

RNA

Spike proteins