Dozens of drugs tested. More than 100 vaccine candidates. With hundreds of clinical trials under way, here is a run down of the major developments in the search for COVID-19 treatments and prevention, reports AFP.
TREATMENTS: AFTER MISFIRES, HOPE – Dexamethasone: saves lives
Cheap and widely available, dexamethasone is a steroid normally used to treat allergic reactions as well as rheumatoid arthritis and asthma.
This week, a team of researchers looking for COVID-19 treatments said that dexamethasone had reduced deaths among the most seriously ill patients by a third compared to regular treatment.
The British government immediately said patients would start receiving the first medicine proven to reduce COVID-19 mortality.
It is not, however, a silver bullet: while researchers believe dexamethasone could save the lives of one-in-eight patients on ventilators, it was shown to have little clinical benefit among less serious cases.
Remdesivir: marginal gains
At least two major US studies have shown the antiviral drug remdesivir can reduce the duration of hospital stays for COVID-19 patients.
Research published in the leading journal the New England Journal of Medicine in May showed that injections of remdesivir — which was originally intended as treatment against Ebola — accelerated patient recovery compared with a placebo.
Washington authorised the emergency use of the medicine on May 1, followed by several Asian nations including Japan and South Korea.
While notable, the drug’s effects do not appear to be miraculous: on average it reduced patients’ hospital stays from 15 days to 11.
One study published in The Lancet, however, found no “significant clinical benefit” from treating coronavirus patients with remdesivir.
Hydroxychloroquine: mixed results
Vaunted by US President Donald Trump as a miracle guard against COVID-19, there is little scientific evidence that the decades-old malaria drug actually works as a treatment.
This month the British research group RECOVERY concluded that the medicine did not help COVID-19 patients at all.
A study in The Lancet — retracted due to problems with the data — claimed that hydroxychloroquine also showed no benefit and even increased the risk of death, prompting several trials to be paused.
On Monday the US withdrew its authorisation for emergency COVID-19 treatment with hydroxychloroquine and a similar medicine, chloroquine.
On Wednesday the World Health Organization announced that hydroxychloroquine can be ruled out as treatment for hospitalised patients.
It did, however, recognise trials under way may show that the drugs have some value as a preventative measure.
Medicine cabinet
Several other medicines intended for other maladies have been trialed against COVID-19.
According to The Lancet there have already been more than 1,000 clinical trials on dozens of pharmaceutical treatments.
Among the most promising are antiretrovirals lopinavir and ritonavir, the antipsychotic chlorpromazine and tocilizumab, an immunosuppressor.
Trials involving transfusing plasma from recovered patients have also shown some potential.