According to the current UK government data, there have been nearly 300,000 confirmed cases of Covid-19, and more than 45,000 people have died.
The scale of this tragedy is therefore huge. And while a vaccine like the one being trialled by Oxford University will (hopefully) prevent or lessen the impact of the virus, it will not take away the need for therapies to treat people who become unwell as a consequence of becoming infected. Even once we have a vaccine that is effective, it will take many months and even years before we have scaled up manufacture and developed the logistics to deliver it worldwide. And treating only a subsection of the world’s population is neither ethical, nor good science.
Infection with Sars-CoV-2 causes a range of health problems, the most common of which is lung inflammation, with resultant difficulty in the transfer of oxygen from the air sacs within the lung (alveoli) to the blood, sometimes referred to as respiratory failure.
On Monday, Synairgen (a University of Southampton spin-out company) announced that a small clinical trial of inhaled interferon beta-1a has shown this treatment may be effective in patients in hospital with Covid-19. But there have been many similar announcements about therapies for the disease that have subsequently been shown to be underwhelming: is this one any different?
Interferon beta-1a is a substance that the body produces naturally as part of its immune response to viral infections. Laboratory data suggesting that interferon beta may help to protect cells, such as those in the lungs, from other coronavirus infections (such as Mers and Sars) led to interest in whether it might be an effective therapy for Sars-CoV-2 infection. Synairgen had previously developed an inhaled form of interferon beta-1a as a therapy for patients with asthma and chronic obstructive airways disease (COPD), so it was well placed to undertake a clinical trial in patients with Covid-19.
The results announced on Monday are from a study that recruited approximately 100 patients from nine hospitals in the UK, and aimed to determine whether the therapy was well tolerated, and if it could prevent or accelerate recovery from respiratory infection caused by Sars-CoV-2. All of the patients recruited into the trial had tested positive for Sars-CoV-2 and were in hospital. The press release claims that the odds of patients clinically deteriorating to the extent they required mechanical ventilation or died was reduced by 79%. Synairgen also claims that patients who received the therapy were more likely to recover over the 14-day treatment period than those who did not.
Have we really found the therapy we have been looking for? Maybe. Maybe not. This clinical trial is small (about 50 patients received the therapy and about 50 patients received the placebo). It was designed to see whether the therapy was tolerated by the patients, and whether it might be effective. So far, we only have a press release suggesting these things may have happened – what we need to see is the actual research data. The claim of a 79% reduction in the risk of needing mechanical ventilation or dying sounds brilliant. I am an intensive care specialist who knows only too well how great the need for a therapy like this is; according to the latest data from the Intensive Care National Audit & Research Centre, more than 7,000 people admitted to UK intensive care units have needed mechanical ventilation, and more than 4,000 people have died. However, we need to remember that only about 50 people received this therapy, and while the press release tells us that three people (6%) who received the placebo died, it does not tell us the number of people who required mechanical ventilation. So we cannot tell how meaningful the effect of this drug is, but the reality is likely to be less striking than the impression given by that “79%”.
If the full research dataset, when it is published, looks good, interferon beta-1a therapy should subsequently be tested in large randomised controlled clinical trials. I am sure there will be people suggesting the therapy should be immediately rushed into routine clinical practice without further testing, but we need to be cautious. There are many examples of therapies that seemed promising in early-phase clinical trials that when tested in larger studies showed no benefit, or even harm.
While I sound a note of caution there is also cause for celebration. This research trial was yet another achievement delivered through the clinical trial infrastructure developed by the National Institute for Health Research that has been so successful during the pandemic. The NIHR has enabled the UK to make world-leading advances in treatments for Covid-19. For example, the Recovery trial has already shown that dexamethasone works for patients in hospital who need oxygen or mechanical ventilation, and that hydroxychloroquine and lopinavir/ritonavir don’t. In addition, the NIHR is supporting a raft of early- and late-phase clinical trials testing other therapies, all alongside delivering multiple vaccine trials.
Covid-19 has led to the NIHR demonstrating that it can deliver healthcare research at a scale and speed unmatched anywhere else in the world, and that is definitely something to be pleased about.
• Dr Charlotte Summers is a lecturer in intensive care medicine at the University of Cambridge
