The faltering progress of hydroxychloroquine (HCQ) as a potential treatment for COVID-19 has again been evident this week as the WHO abandoned its Solidarity Trial of the drug and the FDA revoked approval of HCQ as an emergency treatment for COVID-19.
On 17 June the WHO announced that the Solidarity investigators made the decision to stop recruiting patients into the HCQ arm of the trial after several studies showed that HCQ does not result in the reduction of mortality of hospitalised COVID-19 patients, when compared with standard of care.
The WHO said the halting of the treatment trial did not apply to the use or evaluation of HCQ in pre or post-exposure prophylaxis in patients exposed to COVID-19. In Australia, a trial of low dose HCQ, COVID SHIELD, is still recruiting via the Walter and Eliza Hall Institute of Medical Research in Queensland.
Meanwhile, the FDA said on 15 June that it had determined that chloroquine and HCQ “are unlikely to be effective in treating COVID-19 for the authorised uses in the Emergency Use Agreement.
“Additionally, in light of ongoing serious cardiac adverse events and other serious side effects, the known and potential benefits of CQ and HCQ no longer outweigh the known and potential risks for the authorized use,” it said.
In Australia, the TGA said it was aware of the FDA and WHO’s announcements but said there was no regulatory barrier to HCQ trials continuing in Australia
“Although clinical trials continue around the world, evidence for the safety and effectiveness of hydroxychloroquine to treat or prevent COVID-19 remains limited. The use of hydroxychloroquine for COVID-19 continues to be discouraged other than in a clinical trial setting which would typically be for a seriously unwell patient in hospital,” the regulator said in a statement to the limbic.
“Trial sponsors are responsible for the conduct of clinical trials in Australia with oversight by a Human Research Ethics Committee (HREC) who continuously review the conduct and the safety of the trial.”
The TGA also said that shortages had eased for supply of HCQ for approved use in rheumatic conditions, followed the introduction of prescribing restrictions.
“The supply situation for hydroxychloroquine has greatly improved since the beginning of May. Sponsors and wholesalers have advised that the supply situation is normalising, and wholesalers have progressively eased order limits as demand has decreased.”
The TGA said there is a national shortage of one brand (Hydroxychloroquine GH), which is currently expected to continue until 15 September 2020. Other companies that supply HCQ in Australia have advised that there is stock available.
However the $30 million of HCQ donated by billionaire Clive Palmer could not be re-directed to use in rheumatic disorders, the TGA said.
“The donation by Mr Palmer was not of medicines approved in Australia for Lupus or Rheumatoid Arthritis and so there has not been any rerouting of approved products or supplies to the National Medical Stockpile.
“Hydroxychloroquine will be released from the NMS if and when required, which may include for use in clinical trials,” it said.