Where are the long COVID trials?

The news in early July, 2023, that STOP-PASC, a clinical trial at Stanford University, CA, USA, testing nirmatrelvir-ritonavir in patients with long COVID, is closing enrolment before the full study size has been reached, is disheartening. STOP-PASC is one of the few clinical trials studying a pharmacological intervention for long COVID and although the reason for termination hasn’t been confirmed yet, it adds to the dismal state of clinical research relative to the substantial burden of the condition.

ClinicalTrials.gov currently lists 386 trials under the search term Long COVID. However, only 94 of those studies are classed as interventional and are currently recruiting, and even more disturbing, only 12 trials are testing pharmacological interventions. The rest comprise follow-up of trials in acute infection, rehabilitation, food supplements, telehealth, psychological support, physiotherapy, acupuncture, light therapy, Chinese herbal medicine etc. While the list ranges from “nice to have additional support” to questionable alternative cures or even potentially harmful treatments, we are clearly lacking tested pharmacological interventions that treat the underlying pathophysiology.

There is a desperate need for long COVID treatments. Although estimates vary quite widely between populations and studies and depending on the definitions and methods used, 1 in 10 people experiences long COVID after infection. Lasting symptoms range from mild to disabling, with people unable to work or even bed-bound and unable to take care of basic personal needs. These individual tragedies have wide-ranging repercussions, leading to lost earnings, a shrinking workforce, and increased healthcare and social care costs. Again, estimates vary widely, but the impact is in the range of billions to trillions US dollars globally. Why do we only have 12 pharmacological interventional trials then?