Paris - After a year of vaccines aimed at preventing Covid, treatments for people infected with the virus are few, with most restricted to hospital use and extremely pricey.
Here is a look at treatment options available to Covid patients and how accessible they are.
- Pills to pop -
It's every doctor's dream: a pill to prescribe after a positive test to calm Covid and avoid serious illness -- but a safe and very effective anti-Covid pill has yet to be found.
The most advanced medications are molnupiravir, developed by Merck/MSD and sold under the name Lagevrio, and Paxlovid from Pfizer.
They're antiviral medications that slow down illness by reducing the virus's capacity to reproduce within the body.
Lagevrio was approved for emergency use in the EU and is in the process of being authorised in the US.
But while preliminary results of clinical trials in early October raised hopes for the medication, final results released by Merck/MSD on November 26 were far less promising.
They showed Lagevrio reduced hospitalisations and deaths in high-risk patients who took it at the start of their illness by 30 percent -- not by half as previously estimated.
Other questions surround the safety of the treatment: in theory, its use could lead to the rise of variants of the virus or even cause cancer, although the risks have been deemed small by US experts.
US and EU health officials are looking at clinical trial data on Paxlovid, which is partially based on the anti-HIV medication ritonavir.
One advantage to both antivirals is that because of the way they work in the body they are unlikely to be less effective in the face of new variants of Covid.
They are also the only treatment that exists so far that can be given outside a hospital setting.
- Synthetic antibodies -
Antibodies, which are naturally produced in healthy people to fight infection, can be generated in a lab and given to patients -- but their steep price tag means that kind of therapy isn't for general use.
The World Health Organization (WHO) recommends synthetic antibody treatments for elderly patients and those with suppressed immune systems.
Ronapreve combines synthetic monoclonal antibodies called casirivimab and imdevimab and is administered by a single intravenous injection.
One dose of Ronapreve, developed by the labs Regeneron and Roche, is estimated to cost $2,000 (1,700 euros).
Another complicating factor is that because of the way they work within the body, synthetic antibodies could be rendered less effective in the face of new variants.
Major drug strategies in the battle against Covid-19
On November 30, Regeneron announced their treatment could see its efficacy reduced against the Omicron variant.
The WHO has recommended other synthetic antibodies for even more critical patients including tocilizumab, sold as Actemra or RoActemra by Roche, and sarilumab sold by Sanofi under the name Kevzara.
The molecules are immunosuppressants and should be given alongside corticosteroids.
On Thursday, the UK authorised a monoclonal antibody treatment called sotrovimab, which is from Vir Biotechnology/GSK and is meant to have long-term effects.
Graphic on monoclonal antibodies for the treatment of Covid-19
- Corticosteroids -
Corticosteroids are the first treatment to have been officially recommended by the WHO in September of 2020 and only for the most seriously ill patients.
It fights the inflammation that is characteristic of severe Covid, reducing the risk of death and the need for ventilation.
- What about poor countries? -
According to estimates by Doctors Without Borders (MSF), a few days of Lagevrio or Paxlovid treatments would cost about $700.
Pfizer and Merck have signed voluntary licensing agreements intended to ease the distribution of these drugs outside of rich countries once they are officially authorised.
But that is only the first step for impoverished health systems to get widespread access to the medications.
WHO mass-testing three potential Covid-19 treatments (August 2021)
By Paul Ricard