By Paola Rosa-Aquino and Chas Danner
Vaccines against Covid-19 have been the key weapon for managing the coronavirus’ spread and fending off its most dangerous strains, but pills to treat the virus are on the horizon. So far, pharmaceutical giants Pfizer and Merck have developed experimental antiviral pills – called “Paxlovid” and “Molnupiravir”, respectively – that have shown promising efficacy in clinical trials of adults with Covid-19.
Below is what we know about these new Covid-19 antiviral drugs and when they might be available.
How do they work and how are they different from currently available Covid treatments?
Both antiviral pills – which, unlike other therapeutic Covid treatments, could be available by prescription to take orally at home – bolster the world’s therapeutic arsenal against the virus by reducing its ability to replicate. Both treatments are meant to be taken orally for five days as soon as the first symptoms of Covid-19 appear. Pfizer’s drug, Paxlovid, also includes a low dose of ritonavir (a medicine which is also used to treat HIV) in order to prolong the drug’s effectiveness in the body. Importantly, the antiviral pills aren’t meant to replace highly protective vaccines, but could work in tandem with them to tame the pandemic.
The most significant difference between the Covid antiviral pills and the monoclonal antibody treatments for Covid that are already available is how much easier the pills would be to administer. Monoclonal antibody treatments are administered intravenously at a medical facility in a process which takes about an hour. The two oral medicine treatments are also expected to be less expensive than monoclonal antibody treatments.
How effective are the antiviral pills?
Neither Merck or Pfizer has released detailed data about their clinical trials for their respective antiviral treatments, but the topline results the companies shared seem promising.
- Molnupiravir (Merck and Ridgeback Therapeutics)
- Paxlovid (Pfizer)