As the World Health Organization (WHO) baldly reminds us, “there are no specific vaccines or treatments for COVID-19”. However, trials of treatments are taking place. Some have shown promise in helping those infected by calming an overreacting immune system or targeting the coronavirus – either by destroying it or stopping it from replicating.
Dexamethasone, a widely available steroid that dampens the immune response, became the first medicine shown to reduce deaths in covid-19 patients. The RECOVERY trial of more than 2000 people found that it reduced deaths in people on mechanical ventilators by a third – and by a fifth in those who received oxygen but not ventilation.
“The trial showed it is beneficial to those who are severely affected,” says Sheuli Porkess at the Association of the British Pharmaceutical Industry. It is now being used by the National Health Service in the UK to treat covid-19.
In June, the US bought up virtually all global stocks of the drug remdesivir, an antiviral that suggested promise against Ebola. The move came after one trial found that it reduced recovery time by four days in covid-19 patients.
However, other studies have yielded mixed results: one in April showed no clinical benefit, while an analysis last month by Gilead, the company behind the drug, indicated a reduced risk of death in those severely affected by covid-19. Gilead cautions that more rigorous trials are needed. The drug has received emergency or conditional approval in a number of countries. The litmus test will come in a few weeks with the results of the international Solidarity trial.
Trials are also looking at whether the anti-inflammatory tocilizumab, which is already used to treat arthritis, could be beneficial against covid-19.
Another recent development relates to an inhaler-based treatment that delivers a protein called interferon beta to the lungs. A preliminary finding showed that it reduced the risk of patients going on to develop severe covid-19 by 79 per cent, compared with a placebo group. However, this was a small, early trial of the drug, called SNG001, developed by UK firm Synairgen.
The blood plasma of covid-19 survivors offers another possible treatment because it contains antibodies to the coronavirus. An alliance of companies formed in May to pool research on its use as a therapy for the disease. There are no trial results so far.
New drugs might still emerge. Last week, an analysis of thousands of known drugs that have been approved or are under clinical investigation found 13 that inhibited the coronavirus’s replication in cultured cells.
As well as trying to use existing drugs to tackle covid-19, some pharmaceutical companies are exploring entirely new ones.
In addition, researchers have started to rule out certain drugs. For example, hydroxychloroquine and lopinavir-ritonavir haven’t been shown to provide any benefit, at least in hospital settings.
For now, the focus remains on treating the most severe, short-term problems caused by the illness. But with growing evidence pointing to longer term symptoms, treatments will be needed to tackle those too.
Sign up to our free Health Check newsletter for a monthly round-up of all the health and fitness news you need to know
More on these topics: