Covid-19 study on hydroxychloroquine use questioned by 120 researchers and medical professionals

More than 120 researchers and medical
professionals from around the world have written an open letter to the editor
of the Lancet raising serious concerns about a large and widely publicised
global study that prompted the World Health Organisation to halt several
Covid-19 clinical trials.
On Thursday Guardian Australia revealed
that the Australian data in the study, published last week, did not reconcile
with health department records or databases.
The study found Covid-19 patients who
received the malaria drug hydroxychloroquine were dying at higher rates and
experiencing more heart-related complications than other virus patients. The
large observational study analysed data from nearly 15,000 patients with
Covid-19 who received the drug alone or in combination with antibiotics,
comparing this data with 81,000 controls who did not receive the drug.
Questions about the paper’s statistical
modelling were also raised by Columbia University in the US, prompting
Surgisphere, the company that manages the database of patients used to inform
the study, to issue a public statement defending the integrity of the study.
But now further questions have been raised
about the Surgisphere database and the study methodology. The signatories to
the open letter, directed to the Lancet and the study authors, include
prominent sceptics of the value of using hydroxychloroquine to treat Covid-19.
The letter lists 10 major concerns about the statistical analysis and data
integrity of the study.
“The authors have not adhered to standard
practices in the machine learning and statistics community,” the letter states.
“They have not released their code or data.”
The Lancet is among the many signatories to
a statement on data sharing for Covid-19 studies.
“There was no ethics review,” the letter
continues. “There was no mention of the countries or hospitals that contributed
to the data source and no acknowledgments to their contributions. A request to
the authors for information on the contributing centres was denied. Data from
Australia are not compatible with government reports. Surgisphere have since
stated this was an error of classification of one hospital from Asia. This
indicates the need for further error checking throughout the database.”
The letter also states that the data from
Africa in the study indicates that nearly 25% of all Covid-19 cases and 40% of
all deaths in the continent occurred in Surgisphere-associated hospitals which
had sophisticated electronic patient data recording, and patient monitoring.
“Both the numbers of cases and deaths, and the detailed data collection, seem
unlikely,” the letter says.
The letter also expressed concern about
unusually small reported variances in baseline variables, interventions and
outcomes between continents, despite significant differences in demographics.
There is currently no strong, replicated
evidence that any drug is effective for the treatment or prevention of
Covid-19. This includes hydroxychloroquine, which has long been used for
malaria and autoimmune diseases, but its safety and harm profile for treating
those illnesses is understood. It is not well understood for Covid-19.
Governments around the world have warned
against using hydroxychloroquine for treating or preventing the virus,
highlighting the drug’s potentially toxic side effects and potential to cause
heart abnormalities. There have been serious reports of harm due to people
self-medicating with hydroxychloroquine and related drugs during the pandemic.
Researchers are not calling for clinical
trials to be halted in the light of the Lancet study. There is a consensus that
more strong studies are needed exploring treatments including antibiotics,
antivirals and antimalarials.
“There
is uniform agreement that well conducted RCTs [randomised control trials] are
needed to inform policies and practices,” the signatories to the Lancet letter
said.
Guardian Australia has contacted the
Lancet, Surgisphere and the authors of the study for a response to the concerns
outlined in the letter.
Surgisphere founder Dr Sapan Desai, also an
author on the Lancet paper, said before the release of the letter he
appreciated the “enthusiasm and lively discussion with respect to our important
multi-national observational registry study published in the Lancet medical journal”.
“We appreciate the highly complimentary
responses that we have received and the requests for data-driven partnerships
as well as clarifications,” he said.
“The analyses were carefully performed, and
the interpretations provided were intentionally measured. We studied a very
specific group of hospitalised patients with Covid-19 and have clearly stated
that the results of our analyses should not be over-interpreted to those that
have yet to develop such disease or those that have not been hospitalised. We
also clearly outlined the limitations of an observational study that cannot
fully control for unobservable confounding measures and concluded that off
label use of the drug regimens outside of the context of a clinical trial
should not be recommended.”